report of the committee on chimneys and other heat and

CHI-i C O M ~ I I T T E E P E R S O N N E L

Report of the Committee on Chimneys and Other Heat and

Vapor Removal Equipment

Correlating Commit tee

D. S. Mar t in , Chairman Underwriters' Laboratories of Canada

7 Crouse Road, Scarborough, Ontario M1R 3A9, Canada (Rep. Undewriters' Laboratories of Canada)

Warren M. Apgar, Secretary Insurance Services Division, COMFAL - - Public Protection Grading:

160 Water Street, New York, NY 10038 (Rep. Insurance Services Office)

Joseph F. Schulz, American Society of Heating, Refrigerating, and Air Conditionin~ Engineers

Sectional Commit tee on Incinerators and Waste Handling Systems

Joseph F. Schulz , Chairman Van-Packer Products Company

6th Street and Bay Avenue, Box 211, Beach Haven, NJ 08008 (Rep. American Society of Heating, Refrigerating, and Air Conditioning Engineers)

Wil l i am G. Carpenter , Marshfield, MA L y m a n E. Clark, Veterans Administration E. J. Czaplicke, Wilkinson Chutes, Inc. Lawrence G. Doucet , Syska & Hennessey,

Inc. A. J. Gre~,ory, ECI Air-F|yte Corporation Edwin H. Hoeltke, Christ Hospital

K e n n e t h W. Howell, Underwriters Labora- tories Inc.

C. Allen Ivey, Cerny & Ivey Associates

J o h n P. L a n g m e a d , Gas Appliance Manu- facturers Association

G. M. Watson, American Insurance As- sociation

A l t e r n a t e s

L. J. Dosedlo, Underwriters Laboratories Chappel l D. Pierce, Gas Appliance Manu- Inc. (Alternate to Howell) facturers Association (Alternate to Lang-

mead)

Sectional Commit tee on • Chimneys, Fireplaces and Venting Systems

for Heat Producing Appliances

K. W . Howell , Chairman Underwriters Laboratories Incorporated

333 Pfingsten Roa, d, Northbrook, IL 60062 (Rep. Underwriters Laboratories Inc.)

R E P O R T OF T H E COM~qITTEE ON C H I M N E Y S CHI=2

Wil l iam G. Carpenter , Marshfield, MA

K e n n e t h T. Cucctnelll , American Gas As- sociation

Robert K. H u n t e r , Edison Electric I n s t i - tute

C. Allen Ivey, Cerny & Ivey Associates

Gary" S. Jensen, American Mutual Insur- ance Alliance

J o h n P. L a n g m e a d , Gas Appliance Manu- facturers Assn.

D. S. Mart in , Underwriters' Laboratories of Canada

Joseph Schulz, American Society of Heat- ing, Refrigerating, and Air Conditioning Engineers•

H e r m a n H. S p a e th , Insurance Services Office

Richard, L. S t o n e , Wallace Murray Cor- poration

Merlin L. Taylor, Bricklayers, Ma§ons, & Plasterers International Union of America

G. M. Watson, American Insurance Asso- ciation

Burton L. Weller, National Oil Fuel In- stitute

J. Herbert Witte, Gas Vent Institute

A l t e r n a t e s

Warren M. Apgar, Insurance Services Chappel l D. Pierce, Gas Appliance Manu- Office (Alternate to Spaeth) facturers Association (Alternate to Lang-

Rober t D. Lynch , National Oil Fuel In- mead) stitute (Alternate to Weller) Leo S t a m b a u g h , Edison Electric Institute

• (Alternate to Hunter)

This list represents the membership at the time the Committee was balloted on the text of this edition. Since that time, changes in the membership may have occurred.

Part I. The Committee on Chimneys and Other Heat and Vapor Removal from Cooking Equipment presents for official adoption a complete revision of NFPA 82-1972, Standard on Incinerators and Rubbish Handling. NFP-A 82-1972 is published in the 1977 National Fire Codes, and in separate pamphlet form. The title of this document will be changed to Incinerators, Waste and Linen Handling Systems and Equipment.

Part I has been submitted to letter ballot of the Sectional Committee on Incinerators and Waste Handling Systems, which consists of 11 voting members of whom 6 voted affrmatively, 2 have voted negatively (~tessrs. Pierce and Watson), and 3 did not return a ballot (Messrs. Carpenter, Clarke, and Ivey).

Part I has also been submitted to ballot to the Correlating'Committee, which consists of 3 voting members of whom 3 have voted affrmatively."

Part II. The Committee on Chimneys and Other Heat and Vapor Removal Equipment presents for official adoption a complete revision of.NFPA 211-1972, Standard on Chimneys, Fireplaces and Vents. NFPA'211-1972 is published in the 1977 National Fire Codes, and in separate pamphlet form.

Part IL has been submitted to letter ballot of the Sectional Committee on Chimneys, Fireplaces and Venting Systeins for Heat Producing Appliances," which consists of 75 voting members of whom 9 have voted affirmatively, 3 have voted negatively (Messrs. Schulz, Taylor and Watson), and .3 did not return a ballot (Messrs. Carpenter, Cuccindli, and Ivey).

Part II has also been submitted to ballot to the Correlating Committee, which consists of 3 voting members of whom 2 voted affirmatively and 7 7Joted'negatively (Mr. Schulz).

G E N E R A L 82-5

Part I

Standard on

Incinerators, Wast6 and Linen Handling

Systems and Equipment.

NFPA 8 2 - - 1977

Chapter 1 General-

1-1 Scope.

1-1.1 This standard represents basic requirements pr imari ly ' concerned with reducing the fire hazards encompassing the in-

. staiiation and use of incinerators, waste handling systems, linen (lapndry). handling systems, compactors, and waste storage rooms and containers.

1-1.2 This standard does not include design criteria for the purpose of reducing air pollution. For such criteria, consult the authorities hav!ng jurisdiction.

1-2 Definitions.

1-2.1 Combust ib le Ma te r i a l . Combustible material, as per- taining to this standard, means material made of or surfaced with wood, compressed paper, p l an t fibers, or o ther material that will

Lignite and burn. Such material shall be considered as combustible even though flameproofed, fire-retardant treated, or plastered.

1-2.2 Other definitions relating to this standard are contained in the'Standard Glossary of Terms Relating to Chimneys, .Vents, and Heat Producing Appliances, NFPA 97M-1972.

82--6 INCINERATORS, WASTE AND LINEN HANDLING

Chapter 2 Incineration

2-1 Genera l .

2-1.1 Provision for Auxiliary Fuel. Gas-burning installations shall be in accordance with the National Fuel Gas Code, NFPA 54-1974. Oil-burning installations shall comply with the Standard

Jor the Installation of Oil Burning Equipment, NFPA 31-1974. Fuel burners of all incinerators shall be equipped with safety controls which will automatically shut off the fuel supply to the burner in the event the burner fails to ignite or its flame becomes extin- guished or in the event of insufficient draft.

2-1.2 Electr ical Supply . The electrical supply t o an incinerator shall be installed in accordance with the National Elec- trical Code, NFPA 70-1975.

2-1.3 Air for Combustion and Venti la t ion.

2-1.3.1 Provision shall be made for an adequate supply of air for combustion and ventilation to enter the room in which an incinerator is located. Fans may be installed to deliver air to the incinerator room, provided they are in operation whenever the incinerator is in use.

2-1.3.2 If a residential-type of incinerator is installed in an open area, such as an undivided basement without storm windows and without unusually tight fitting doors, in buildings of conven- tional construction, adequate air supply may usually be obtained through normal air infiltration. If the incinerator is located in a confined space or an area separated by tight-fitting partitions and doors, adequate air shall be provided by. means of an opening communicating with other areas of the building having adequate infiltration or with the outdoors. See NFPA 31-1974, Standard for the Installation oJ Oil Burning Equipment.

2-1.3.3 Rooms in which incinerators other than residential types are installed shall be furnished air for combustion' and ventilation by one of the' following means :

(a) A screened or louvered ventilator opening or other suitable air intake. If communicating to other parts of the building, the opening shall be protected by an approved fire damper.

(b) A duct leading from the incinerator room to the outdoors.

(c) A duct leading to a boiler or furnace room cut off as prescribed in 2-2.10 or 2-3.6, and provided with sufficient air supply for both rooms.

INCINERATION 8 2 - 7

2-1.3.4 The opening or duct specified in 2-1.3.3 shall have a free area of not less than l sq. in. per 4,000 Btu per hour incinerator burning rate based on heat value of waste and auxiliary fuel, if all air is from the outdoors; and 1 sq. in. per 1,000 Btu per hour incinerator burning rate if all air is from inside buildings. See the National Fuel Gas Code, NFPA 54-1974.

2-1.3.5 Air ducts extending to or from an incinerator room through other parts of a building shall be constructed and installed in accordance with the Standard Jor the Installation of Air Conditioning and Ventilating Systems, NFPA 90A-1976.

2-1.4 Spark Arresters.

2-1'.4.1 Spark arresters shall be used.

2-1.4.2 The net free area of the arrester shall be not less than four times the net free area of the outlet of the chimney flue it serves.

2-1.4.3 Arresters shall have a vertical height of not less than 1.3 times the minimum diameter of the chimney flue or the minimum horizontal dimension of rectangular chimney flue.

2-1.4.4 Arresters, including bolts, rivets, screws and supporting members, shall be made of stainless steel (ASTM A167,1 Type 316, or A S T M A478, Type 316, or the equivalent).

2-1.4.5 Openings shall not permit the passage of spheres having a diameter larger than one-half inch, nor block the passage of spheres having a diameter of less than three-eighths inch.

2-1.4.6 Means shall be provided for securely attaching the spark arresters to chimneys to provide adequate support and prevent movement of the arrester.

2-1.4.7 Means shall be provided to replace spark screens.

2-2 Domestic Incinerators.

2-2.1 Definitions. A domestic incinerator is for the burning of ordinary combustible waste material and garbage incidental to residential occupancy and-having a firebox of charging compart- men t of not over 5 cu. ft. of furnace volume. Domestic incinerators may be self-contained, factory-built units not requiring field construction, or may be of the built-in type designed to be encased in masonry or installed in a masonry wall or chimney.

1The full title and date of all references to ASTM standards in this standard appear in the Appendix.

8 2 - - 8 I I ~ C I N E R A T O R , q ~ W A S T E A N D L I N E N H A N D L I N G

p

2-2.2 Design and Construction.

2-2.2.1 T h e design shall be such tha t in service the inciner- a tor will not crack, warp, or otherwise fail s t ruc tura l ly so as to per- mi t f lame passage or emission of combust ion gases or sparks into the bui lding.

2-2.2.2 Explosion relief shall be provided. T h e area of explosion relief shall be not less than one square foot of relief a rea for every 100 cubic feet of p r ima ry combust ion c ha mbe r volume. W h e r e the ch imney will not serve the above purpose, a door or pane l shall be provided and a r ranged to al low the door or panel to re turn to a closed posit ion p rompt ly af ter pressure has been released. .

2-2.2.3 Self-contained, fac tory-bui l t domest ic incinerators shall be approved types.

2-2.2.4 T h e enclosing walls for combust ion chambers of bui l t - in incinerators shall be const ructed of c lay or shale bricks not less than 4 inches in thickness wi th a l ining of 41/~ inches of h igh-du ty f ireclay refractory• F i rebr ick and mor tars shall not ' be less than h igh-du ty fireclay refractory conSplying with the requirements ,o f A S T M C64-72, Specifications for Refractories for Incinerators and Boilers.

Exception: Other constructions may be used, i f equivalent to the constructions outlined in 2-2.2 in structural strength, insulating value, and ability to withstand thermal expansion and.flame impingement.

2-2 .3 P l a c e m e n t . Inc inera tors shall be p laced on the g round or on floors of fire-resistive construct ion with noncombus t ib le flooring or surface finish and with no combust ib le ma te r i a l agains t the unders ide thereof, or on noncombus t ib le slabs or arches having no combust ib le mate r ia l against the unders ide thereof. Such con- s truct ion shall extend not less than 18 in. beyond the front of the inc inera tor or s ide where ashes are removed and 12 in. beyond all o ther sides of the incinerator .

Exception No. 7: An incinerator which is listed specifically for placement on combustible .floors shall be installed in accordance with the terms of such listing and the manufacturer's instructions.

Exception No. 2: An incinerator may be placed on floors other than as specified in 2-2.3 provided the incinerator is so arranged that .flame or hot gases do not come in contact with its base and, further, provided the floor under the incinerator is protected with hollow masonry not less than 4 in. in thickness, covered with sheet metal of not lighter than 24 U.S. gage. Such masonry course shall be laid with ends unsealed and joints

t

I N C I N E R A T I O N 8 2 - 9

matched in such a way as to provide a free circulation of air from side to _ . % 1 . J l . . . . . . . i . b l l ~ j ! . . . . . . . . . . . . D . . . . J7~__ qoi o " L . . . . . .g JL~ a ~ J 0 f ~L~ atu~ ~tttuugtt tttuauttt f. Tlie ./tuut jut in. uc),u,,,, ~,,~ j , u,,n ,,,o incinerator or side where ashes are removed anal 72 in. beyond all other sides of the incinerator shall be protected with not less than 1~ in. asbestos millboard covered with sheet metal of not lighter than 2d U.S. gage or with protection equivalent thereto.

Exception No. 3: An incinerator which is set on legs that provide not less than 4 in. open space under the base of the incinerator may be placed on floors other than as specified in 2-2.3 provided the incinerator is such that flame or hot gases do not come in contact with its base and, further, provided the floor under the appliance is protected with asbestos millboard not less than 1~ in. thick covered with sheet metal not lighter than 24 U.S. gage• The above specified floor protection shall extend not less than 78 in. beyond the

front of the incinerator or side where ashes are removed and 72 in. beyond all other sides of the incinerator•

2-2.4 Clearances.

2-2.4.1 T h e clearances above a charging door to combustible ma te r i a l shall be not less than 48 in.

Exception No. 7: Incinerators mhich are listed specifically for installation at lesser clearances shall be installed in accordance with the terms of such listing and the manufacturer's instructions, provided that; in any case, the clearances shall be suffcient to afford read), accessibility for firing, cleanout, and an), necessary servicing.

Exception No. 2: The clearance may be reduced to 24 in. provided the combustible material is protected with sheet metal not lighter than 28 U.S. gage spaced out 7 in. on noncombustible spacers, or equivalent protection. Such protection shall extend 78 in. beyond all sides of the charging door" opening•

2-2.4.2 An inc inera tor s h a l l be instal led to provide c lear- ances between it and -combus t ib l e ma te r i a l of n'ot less than 36 in. a t the sides, rear , and top and not less than 48 in. a t the front.

Exception No. 1: Incinerators which are listed specifically for installation at lesser clearances shall be installed in accordance with the terms of such listing and the manufacturer's instructions, providOd that, in an)' case, the clearances shall be. suffcient to afford read3, accessibility, .for .firing, cleanout, and any necessary, servicing.

Exception No. 2: Domestic incinerators may be installed with reduced clearances to combustible material when the combustible material is protected in accordance with Table 2-2. 1 and Figure 2-2. 1 of the Manual on Clearances for Heat Producing Appliances, NFPA 8 9 M - 7 9 7 6 . Clear- ances shall not be reduced in confined areas such as alcoves•

82-10 INCINERATORS, WASTE AND LINEN HANDLING

2-2.5 Chimneys for Domestic Incinerators.

2-2.5.1 Domestic incinerators shall be connected to chimneys.

Exception: Where domestic incinerators are installed in spaces open to outside air but provided with a cover or roof such as open sheds, breezeways, 'or carports, galvanized steel pipe not less than 20 galvanized sheet gage number or other, equivalent noncombustible fire-and-corrosion-resistant material may be used provided the pipe is exposed and readily examinable for its ful l length and clearance not less than 18 in. is maintained from combustible material. The pipe shall extend at least 3 f t . above the highest point where it passes by or through a roof and at least 2 f t . higher than any portion of a building within /Of t . I f the pipe passes through a roof constructed of combustible material, it shall be guarded by a ventilating thimble of galvanized steel or approved corrosion-resistant noncombustible material extending not less than 9 in. below and 9 in. above the roof construction, and of a size to provide not less than 6 in. clearance on all sides of the pipe; or the combustible material in the roof construction shall be cut away so as to provide not less than 18 in. clearance on all sides of th~ pipe, with any material used to close up such opening entirely noncombustible.

2-2.5.2 Chimneys shall conform to the Standard for Chimneys, Fireplaces, and Vents, NFPA 211-1972.

2-2.5.3 An incinerator with integral vent shall be listed and shall be installed in accordance with the terms of the listing and the manufacturer 's instructions.

2-2.5.4 An automatic draft control, if furnished with the incinerator, shall be installed in accordance with the instructions furnished with the incinerator.

2-2.6 Chimney Connector.

2-2.6.1 The clearance between a single-wall, metal pipe connector and unprotected combustible material shall be not less than 18 in. The clearance between a connector made of Type L venting-system piping and unprotected combustible material shall be not less than 9 in.

Exception: "These clearances may be reduced if the combustible material is protected in accordance with the Standard for Chimneys, Fireplaces, and Vents, N F P A 2 1 / - 1 9 7 2 .

2-2.6.2 A chimney connector shall not be enclosed. The connector .throughout its entire length shall be readily accessible for inspection and replacement.

INCINERATION 8 2 - 1 1

2-2.6.3 A chimney connector or vent connector shall not pass through any floor or ceiling.

2-2.6.4 A connector shall not pass through a wall or partition constructed of combustible material.

Exception: A connector may pass through a wall constructed of combustible material only when it is guarded at the point of passage by:

(a) Metal-ventilated thimble not less than 72 in. larger in diameter than the connector.

(b) Metal or burned fire-clay thimble built in brickwork or other approved fi?eproofing materials extending not less than 8 in. beyond all sides of the thimble.

(c) In lieu of a thimble, all combustible material in the wall or partition shall be cut away from the connector a sufficient distance to provide the clearance required from such connector. Any material used to close up such opening shall be noncombustible insulating material.

2-2.6.5 Draft Hoods Prohibited. Draft hoods shall not be installed on incinerators.

2-2.7 Waste Chutes. A waste ehute shall not feed directly into a domestic incinerator.

2-2.8 Instructions. Instructions shall be posted in a per- manent manner on the charging door of domestic incinerators warning against the introduction of loose dusty materials, flam- mable liquids or compounds, and closed containers and aerosol cans (empty or otherwise).

2-2.9 Incinerator Rooms for Domestic Incinerators. In- cinerators shall be enclosed within a room separated from other parts of the building by wall, partition, floor or floor-ceiling assemblies having a fire resistance of not less than 1 hour, and used for no other purpose except storage of containers of waste materials to be burned, and building heating equipment.

Exception: In private dwellings occupied by not more than two families, a domestic incinerator need not be in a separate room provided minimum clearances prescribed for domestic incinerators in 2-2.4 are provided.

2-3 Commercial-Industrlal Incinerators.

2-3.1 Definition. A commercial-industrial incinerator is one having a furnace volume in excess of 5 eu. ft.

2-3.2 Design and Construction.

82-12 I N C I N E R A T O R S ~ " W A S T E A N D L I N E N H A N D L I N G

2-3.2.1 The design shall be such that in service the in-

to permit flame passage or emission of combustion gases or spa~:ks into the building.

2-3.2.2 Explosion relief shall be provided. The area of explosion relief shall be not less th~n one square foot of relief area for every 100 cubie feet of primary combustion chamber volume. Where the exhaust chimney will not serve the above 'purpose, a door or panel shall be provided and arranged to allow the door or panel to return to a closed position promptly after pressure has been released.

2-3.2.3 Commercial-industrial incinerators shall be built in accordance with the following requirements:

(a) All combustion shall take place Within the combustion chamber designed for combustion temperatures. Combustion shall not take place in breeching or chimneys unless they are designed as combustion chambers.

(b) Incinerators designed for positive pressures shall be gas tight.

t ~ .r~ . . . . 1. . . . . " ~ ~ t . ~ . ~ _ " ' idg ~,~j .~,,~ ,~u,,L,u~u,.,,, ~,,,~,,u~,, mncr walls, roofs, br es, walls, and curtain walls shall be so constructed as to withstand the combustion temperatures involved and shall maintain their integrity under all operating conditions. Metal stays, lintels, or

• other supports shall not be exposed to the interior of the combustion chamber.

(d) An exterior masonry casing shall be reinforced with structural steel framework and an exterior steel casing shall be reinforced with structural steel members, such that the casing will withstand interior thrusts from arches and be capable of supporting all doors and burner equipment. The steel casing or framework shall be erected and set plumb before any brickwork is done. Cylindrical outer casings made of steel not less than 1/4 inch thick need not be reinforced.

(e) Insulation shall be used between the external casing and the inner walls as required to meet the temperature limita- tions of 2-3.2.5.

(f) Openings shall be provided so that all parts of the incinerator can be cleaned, including the ash pit,. the combustion chamber, the passes of separation chambers, and the incinerator flue. Cleanouts shall be closed by tight-fitting d6i~rs or covers, securely latched or otherwise held in a closed position. Ash pit and combustion chamber closures and frames shall be of cast iron or equivalent, with the frames securely attached to the incinerator.

I l g I C I N E R A T I O N 8 2 - - 1 3

2-3.2.4 No part .of an incinerator shall be used as a wa!l, x v v x v x a , ~ v l v x ~ ~ x A ~ x ~ .

2-3.2.5 Incinerators slaall be so designed that the temperature rise above ambient (75°F :t= 5 °) of any portion of the incinerator casing accessible to an operator shall not exceed 70°F. Handles of operating doors shall_not exceed a 40°F rise for metallic and 60°F rise for nonmetallic.

Exception: Doors, inspection points, burn,s , flues, and areas immediately adjacent thereto need not comply with 2-3.2.4.

2-3.3 Placement . Commercial-industrial incinerators shall be placed on properly designed foundations of masonry or reinforced concrete or~on noncombustible material having a fire resistance rating of not less than 3 hours provided such support is independent of the building construction and the load is transferred to the ground.

2-3.4 Clearances.

2-3.4.1 Commercial-industrial incinerators shall, be installed to provide a clearance to combustible material of not less than 36 in. at the sides and rear, and not less than :18 in. above, and not less than 8 ft. at the front of the incinerator.

Exception." For a commercial-industrial incinerator encased in brick the clearance above may be 36 in. and at the sides and rear it may be 78 in.

2-3:4.2 A clearance of not less than 12 in. shall be provided from the incinerator to walls or ceilings of noncombustible construction.

Exception: A clearance o f not less than 3 in. may be provided from commercial and industrial incinerators to walls or ceilings of noncombustible construction where it is not possible to place combustible .material on the outer or upper side thereof.

2-3.4.3 Incinerators which are listed specifically for installation at lesser clearances than specified in 2-3.4.1 and 2-314.2 shall be installed in accordance with the conditions of such listing, provided that,, in any case, the clearances shall be sufficient to afford accessibility for firing, cleanout, and any necessary servicing as set forth in 2-3.4.4.

2-3.4.4 Sufficient space shall be provided around the incinerator and its appurtenances to facilitate cleaning, repair, and

, servicing. Clearance shall be provided to allow the cleanout doors to be completely opened so that all parts of the combustion

t ~

82-14 I N C I N E R A T O R S , ~ r A S T E AND L I N E N H A N D L I N G

chamber, ash pit, separation chambers, etc., may be reached and so implements used for this purpose can be freely manipulated. All dampers, gates, burners, valves, levers, etc., shall be accessible for repair and adjustment or replacement. No construction shall be located closer than 16 in. to any part of an incinerator.

Exception: Noncombustible structural member 2 f t . wide or less, parallel to the incinerator, may be located as close as 6 in. to the incinerator, provided such members do not reduce accessibility to any moving parts of the incinerator.

2-3.5 Charg ing Hood and Chute. (See 3-3. 5.)

2-3.5.1 The combustion chamber of a commercial-industrial type incinerator may be charged through the floor immediately above such incinerator.

2-3.5.2 The charging hood and chute shall be constructed of not less than 12 U.S. gage steel casing, lined with not less than 41/-~ in. of firebrick (ASTM C64 Type F, medium duty, or the equivalent). Such charging h6pper shall not exceed 6 ft. in length measured from the floor opening to the outside of the roof of the incinerator combustion chamber.

Exception: The charging hood and chute may exceed 6 f t . in length if approved means are provided to prevent the charging hood and chute from discharging gases resulting from combustion into the charging room.

2-3.5.3 The charging opening shall b e protected by a cover extending beyond the edges of the opening for at least 2 in. on all sides, and lined with not less than 2 ~ in. of refractory material.

2-3.5.4 The charging floor opening shall be located in a room with walls and floor and ceiling assemblies having a fire resistance rating of not less than 2 hours, with openings protected by approved self-closing or automatic-closing 3-hour fire doors suitable for Class A openings. Such doors shall be kept closed during the charging operation; also at other times except when delivering waste material to the room.

Exception: When the room is protected by an approved system of automatic sprinklers, the walls, and floor and ceiling assemblies may have a fire resistance rating of not less than I hour and the door may be a l l~-hour fire door approved for Class B openings.

2-3.6 Incinerator Rooms for Commercial-Industrial In- cinerators.

2-3.6.1 Commercial-industrial ~ncinerators shall be enclosed within a room separated from other parts of the building by wall, partition, floor, and floor-ceiling assemblies constructed

o INCINERATION 82-15

of noncombustible material and having a fire resistance rating of not less than 2 hours and used for no other purpose.

Exception: Storage containers of waste material to be burned and building heating equipment may be located in the.inciherator room.

2-3.6.2' Door or other openings in rooms containing incinerators communicating with other areas of the building shall be protected by approved self-closing or automatic-closing 1 a/~-hour fire doors suitable for Class B openings.

2-3.6.3 Automatic sprinklers, a short length of hand hose connected to a suitable water supply, and a suitable floor drain shall be provided in the incinerator room.

2-3.7 Chimneys for Commercial-Industrial Incinerators.

2-3.7.1 General.

2-3.7.1.1 The chimney flue for a commercial-industrial incinerator shall serve the incinerator only. I t shall be designed and proportioned to proyide adequate draft for proper operation of the incinerator.

2-3.7.1.2 Chimneys shall be supported on properly designed foundations of masonry or reinforced portland or refractory cement concrete. They shall be so constructed as not to place excessive stress upon the roof of the combustion chamber. If incinerator walls are to support the chimney, the foundation and walls shall be built to support the load imposed.

Exception: Masonry chimneys may be supported on noncombustible material having a fire resistance rating of not less than 3 hrs. where such supports are independent of the building construction and the load is transferred to the ground.

2-3.7.1.3 A factory-built chimney, if so listed, and a metal chimney may be supported additiohally at intervals by the building structure, in which case expansion joints shall be provided at each support level. All joints shall be liquid tight or of a design such that liquid will drain to the interior of the chimney.

2-3.7.1.4 Cleanout openings provided in chimneys shall be equipped with ferrous metal doors and frames arranged to remain tightly closed when not in use. A clearance of not less than 36 in. shall be provided between cleanout doors and combustible material.

2-3.7.1.5, Drains shall be provided at the base of all chimneys to allow the removal of condensed flue products and shall be designed to avoid clogging.

82-16 INCINERATORS~ WASTE AND LINEN HANDLING

2-3.7.2 Lis ted M e d i u m - h e a t C h i m n e y s . Listed medium- heat appliance chimneys may be used and shall be installed in accordance with the conditions of the listing and the manufacturer's instructions.

2-3.7.3 Me(al Chimneys.

2-3.7.3.1 Where secondary combustion temperatures do not exceed 1800°F, metal chimneys shall be lined with 4 ~ in. of high-duty, spall-resistant firebrick (ASTM C64) laid in high-duty refractory mortar (ASTM C105). The lining shall start at the base of the chimney and extend continuously to the top. Equivalent lin-

• ings of equiv,/lent thickness, such as Class A or better Alumina- Silica Base Castable Refractories or Class O or better Insulating Castable Refractories, may be used. Equivalent thickness shall be that thickness capable of providing the same insulating and structural values to limit skin temperatures to those specified in 2-3.2.5 under all intended operating conditions.

2-3.7.3.2 Where secondary combustion temperatures'exceed 1800?F; metal chimneys shall be lined with 4 ~ in. of super- duty, spfill-resistant refractory brick (ASTM C64) laid in refractory mortar. The refractory mortar shall be high-duty for temperatures up to 2730°F and super-duty or better for temperatures up to 2910°F. The lining shall start at the base of the chimney and extend continuously to the top. Equivalent linings of equivalent thickness, such as Class B or better Alumina-Silica Base Castable Refractories (ASTM C64) in accordance .with temperature requirements or Class• P and Q Insulating Castable Refractories (ASTM C64) in accordance with temperature requirements, may be used. Equivalent thickness shall be that thickness capable of providing the same insulating and structural values to limit skin temperatures to those specified in 2-3.2.5 under all intended operating conditions.

2-3.7.3.3 Castable plastic refractories, or other refractories, may be used i.n metal chimneys in lieu of firebrick provided such refractory is of equivalent heat and corrosion resistance. Liners made of these refractories shall be supported by anchors made of corrosion resistant steel capable of supporting the refractory load at 1500°F. The insulating value shall be such that temperatures at the supports shall not exceed this temperature under all firing conditions.

2-3.7.3.4 Metal chimneys shall be properly riveted or welded, securely supported and constructed in accordance with good engineering practice.

INCINERATION 82-17

2-3.7.3.5 Metal chimneys shall be constructed of steel or cast iron. Sheet steel shall have a thickness not less than that indicated in Table 2-3.7.3.5.

Table 2-3.7.3.5 MinimumThickness of Sheet Steel Chimneys

Mfgr. Std. Gage No.

16 14 12 10

Min. Thickness in. (mm)

.054 (1.37) .069 (1.75) .098 (2.49) .128 (3.25)

Area in. 2/m 2

up to 154/.0994 155/.0999 to 201/.1296 202/.1303 to 254/.1638 Larger than 254/.1638

Equiv. Round Diam.

in. /mm

up to 14/356 over 14/356 to 16/406 over 16/406 to 18/457

over 18/457

NOTE: Regardless of mimmums in this table, the thickness of sheet metal shall be adequate to meet the requirements of 2-3.7.3.6.

/

2-3.7.3.6 Metal chimneys shall be properly riveted, welded or bolted, securely supported and constructed in accordance with good engineering practice as necessary for the •following:

(a) Strength to resist stresses due to steady or gusting wind loads.

• (b) Adequate anchoring, bracing, and inherent strength to withstand seismic and, wind-induced vibrational stresses.

(c) Proper material thickness for durability considering fuel analysis, gas temperature, and exposure.

(d) Security against leakage of flue gases under positive pressure.

(e) Allowance for thermal expansion of breeching and vertical sections.

2-3.7.3.7 If a metal chimney extends through any story of a building above that in which the connected incinerator is located, it shall be enclosed in such upper stories within contihuous wails constructed of materials which are noncombustible, such as masonry (see 7-2. 7)~ and extending from the ceiling of the in- cinei-ator room to or through the roof so as to retain the integrity of the fire separations as required by applicable building code provisions. The walls shall have a fire resistance rating of not less -than 1 hour if the building is less than 4 stories in height, and not less than 2 hours if the building is 4 or more stories in height, and shall conform to the following:

(a) The enclosure shall provide a space on all sides of the chimney sufficient to permit inspection and repair, but in no ease shall it be less than 12 in.

82-18 INCINERATORS, WASTE AND L I N E N HANDLING

(b) The enclosing walls shall be without openings.

Exception: Doorways equipped with approved selJ-closing l l/2-hour fire doors approved Jor Class B openings may be installed at various floor levels for inspection purposes.

2-3.7.4 Masonry Chimneys.

2-3.7.4.1 Where secondary combustion temperatures do not exceed 1800°F, masonr3~ chimneys shall be constructed of solid masonry units or reinforced concrete with walls not less than 8-in. thick. Such Walls shall be lined with 41~ in. high-duty, spall-resistant firebrick (ASTM C64) laid in high-duty refractory mortar (ASTM C105). The lining shall start at the base of the chimney and extend continuously to the top.

2-3.7.4.2 Where secondary combustion temperatures exceed 1800°F, masonry chimneys shall be constructed with double walls of solid masonry units or reinforced concrete, each wall to be not less than 8 in. thick with an air space of not less than 2 inches between them. The inside of the interior wall shall be lined with 41/~-in. super-duty, spall-resistant firebrick laid in super-du@ refractory mortar (ASTM C64). The lining shall, start at the base of the chimney and extend continuously to the top.

2-3.7.4.3 Masonry chimneys shall I~e proved air tight by a smoke test after erection and before being put into service.

2-3.8 Chimney Clearances.

2-3.8.1 Listed chimneys shall be installed in accordance with the conditions of the manufacturer's instructions as to clearances. Exposed portions of chimney or breechings that can be touched shall be so designed that maximum surface temperatures shall not exceed 70°F above ambient temperature.

2-3.8.2 Masonry Chimneys. A clearance of not less than 4 inches shall be provided between the" exterior surface of masonry chimneys and combustible material.

2-3.8.3 Exterior Metal Chimneys,

2-3.8.3.1 Exterior metal-chimneys shall have a clearance of not less than 24 inches from a wall of wood frame construction and from any combustible material.

2-3.8.3.2 Exterior metal chimneys over 18 in. in diameter shall have a•clearance of not less than 4 in., and those 18 in. or less in diameter a clearance of not less than 2 in. from a buildifig wall of other than wood frame construction.

INCINERATION 82--19 ti~

2-3.8.3.3 An exterior metal chimney shall be installed with a minimum clearance of 24 in. to any door or window or to any walkway, unless insulated or shielded in any approved manner to avoid burning a person who might touch the chimney.

2-3.8.4 Interior Metal Chimneys.

2-3.8.4.1 Within the same story of a building as that in which the incinerator is located, a metal chimney shall have a clearance of no t less than 36 in. from a wall of wood frame construction and from any combustible material. Such interior metal chimneys over 18 in. in outside diameter shall have a clearance of not less than 4 in., and those 18 in. or less in outside diameter a clearance of not less than 2 in. from a building wall of other than wood frame construction.

2-3.8.4.2 If a metal chimney passes through a roof constructed of combustible material, it shall be guarded by a ventilating thimble of galvanized iron or approved corrosion resistant metal, extending not less than 9 in. below and 9 in. above the roof construction, and of a size to provide not less than 18 in. clearance on all sides of the chimney.

2-3.9 Chimney Termination.

2-3.9.1 Chimneys on incinerators where the secondary combustion chamber is designed to be operated at 1800°F or less shall extend not less than 10 feet higher than any portion of any building within 25 feet.

Exception:" Such portions do not include other chimneys, vents or open structural .framing.

2-3.9.2 Chimneys on incinerators where the secondary combustion chamber is designed to be operated at 9ver 1800°F shall extend not less than 20 feet higher than any portion of any building within 50 feet.

Exception: Such portions do not include other chimneys, vents or open structural Jraming.

2-3.9.3 The terminus of the chimney flue for the incinerator shall be equipped with an approved spark arrester if the incinerator does not include effective means for arresting sparks and fly ash (see 2-1.4).

2-3.9.4 Chimneys for incinerators of special design to pro- duce low flue-gas temperatures shall adhere to the construction specified above. (For further explanation, see 2-3.10.7.)

82--20 INCINERATORS, WASTE AND' LINEN HANDLING INCINERATION 82--21

2-3.10 Chimney Connector or Breeching.

• 2-3.10.i A ch imney connec tor or breeching connect ing a commerc ia l - indus t r ia l type inc inera tor to a ch imney sha l l be con- s t ructed of not l ighter than 16 U.S. gage steel if it is 12 in. or less in d i a m e t e r ' o r greatest cross-section dimension, and of not l ighter than 12 U:S. gage steel if it exceeds 12 in. in di~/meter or greatest cross-sect ion dimension.

Exception: Breechings may also utilize listed medium-heat chimney sections if these sections are joined together with con'tinuous welds, .flanges, or couplings.

2-3.10.2 Ch imney connectors or breeching up to 18 in. in d i ame te r or greatest cross-section ctimension shall be l ined with not less than 21/~-in. h igh-duty , spal l -resis tant r e f r a c t o r y br ick ( A S T M C64). ..

2-3.10.3 Ch imney connectors or breeching• over 18 4n. in d i ame te r or greatest cross-section d imension shall be l ined with no t less than 4a/~ ' in. of h igh-du ty spal l-resistant ref rac tory br ick ( A S T M C64).

2-3.10.4 Cas table plast ic refractories, or o ther refractories, m a y be used in lieu of f irebrick provided such refractory is of equiv- a lent hea t and corrosion resistance• Liners made of these refractories shall be suppor ted by anchors made of corrosion re- s is tant steel capab le of suppor t ing the ref rac tory load at 1500°F. T h e insulat ing value .shall be such tha t t empera tu res at the supports shall not exceed this t empe ra tu r e u n d e r all firing condit ions.

2-3.10.5 T h e net in ternal free a rea of the connector shall be not less than the free a rea of the flue col lar of the incinerator .

2-3.10.6 A ch imney connec tor shall not be enclosed. T h e connec tor th roughout its ent i re length shall be readi ly accessible for inspection and• rep lacement .

2-3.10.7 Ch imney connectors or breechings of all commerc ia l - indust r ia l type incinerators , inc luding those of special design to p roduce low flue-gas tempera tures , shall conform with 2:3.10.1 th rough 2-3.10.57

ZThis requirement has been initiated to avoid the serious .corrosion prob- lems inherent with low-temperature incinerator-flue gases. - It also provides the high-temperature protectionnecessary when the special equipment is bypassed for any.purpose, including power failure. In those cases where the bypass is such that the breeching is also bypassed, '.then the breeching need not be high-temperature protected but it shall be protected by. an acid-resistant coating suitable for the operating conditions.

2-3.10.8 If a gas washer or scrubber is used or if o ther ar- . . . . ~ . . . . . . . . . . . . . . . . . . . . . . . . . ~ ,,~tu, m u~mt i~ insuv~cient for p roper opera t ion of the i nc ine ra to r , ' a d ra f t inducer m a y be used. In this dvent, the ch imney shall be sized for na tu ra l -d ra f t opera t ion and a bypass instal led a round the gas washer or sc rubber or o ther uni t that requires the dra f t induct ion. Sui tab le no rma l ly open damper s shall, be instal led in the bypass to' al low vent ing of combust ion products in the event of power fai lure.

2:3.10.9 Expans ion jo in ts shall b e p r o v i d e d as required.

2-4 O u t d o o r I n c i n e r a t o r s . All ou tdoor incinerators shall conform with Chapte rs 2 and 3, depend ing upon use.

I

82-22 INCINERATORS~ WASTE AND LINEN HANDLING

Chapter 3 Waste Chutes and Handling Systems t

3-1 Definitions. There are four types of waste chute systems, each with separate fire safety criteria.

3-1.1 General Access Gravity Type. A waste chute of this type is an enclosed vertical passageway in a building to a storage or compacting room where the waste is transferred by gravity only. All occupants of the building are free to use the chute at any time.

3-1.2 Limited Access Gravity Type. A waste chute of this type is an enclosed vertical passageway in a building to a storage or compacting room where the waste is transferred by gravity only. Authorized personnel only may use the chute, gaining entry by key to a locked chute door or service opening room door.

3-1.3 Pneumatic Waste Handling Systems. A waste handling system of this type is a vertical, horizontal, or inclined duct having sufficient mechanically applied air-flow to convey refuse without clogging to point of.disposition.

3-1.4 Gravity-Pneumatic Waste Handling System. A system using a combination of the types defined in 3-1.1 through 3-1.3. The gravity type usually feeds into a pneumatic waste handling system.

3-2 Construction. 3-2.1 General.

3-2.1.1 A steel or steel-jacketed refractory chute supported at intervals by the building structure shall be provided with expansion joints between support levels. Other chutes shall be supported upon a substantial noncombustible foundation having a fire resistance rating of at least 3 hours.

3-2.1.2 Gravity chutes shall be constructed straight and plum b with no offsets. A minimum clearance of 24 in. shall be maintained from the outside edge of the discharge of the chute to any wall. All chute interiors shall be smooth and without projections.

Exception: When connected to a compactor or other device for processing the waste, clearance on two sides may be 4 in.

3-2.1.3 Listed medium-heat appliance chimney sections shall be acceptable for use as rubbish chutes.

~Waste chutes, conveyors, or other handl ing systems are usually employed where there is a relatively large area on each floor from which rubbish is collected. The collected rubbish is brought to the opening-in the chute. The chute then conveys the refuse to its disposition point.

WASTE CHUTES AND HANDLING SYSTEMS 82-23

3-2.1.4 Vertical rubbish chutes shall be enclosed in all stories above the storage or compacting room within a continuous enclosure constructed of materials which are noncombustible, and extending from the ceiling of the storage or compacting room to or through the roof so as to retain the integrity of the fire separation as required by applicable building code provisions. The walls of the enclosure or the walls of the masonry chute shall have a fire resistance rating of not less than 1 hour if the building is less than 4 stories in height and not less than 2 hours if the _building is 4 or more stories in height. (For pneumatic waste handling systems with horizontal runs, see 3-2.4.)

Exception: Masonry chutes conforming to 3-2.2 or constructed oJ masonry walls having a fire resistance rating not less than specified above are not required to be enclosed.

3-2.1.5 The size of a refuse chute shall be in accordance with the following:

(a) Gravi ty T y p e Chutes. The size of the chute shall not be less than 221~ by 221/'~ in. or 24 in. in diameter, inside measurement.

(b) Pneumatic Waste Handling Systems. The size of the duct shall not be less than 16 in., inside measurement.

Exception: When all materials entering the pneumatic-powered chute are processed through a shredder the chute may be less than 76 in. in accordance with the authority having jurisdiction.

3-2.1.6 A waste chute shall extend (full size) at least 4'ft. above the roof of the building. The chute shall be open to the atmosphere.

3-2,2 Masonry Waste Chutes. Masonry waste chutes shall be constructed of clay or shale brickwork not less than 8 in. thick or of reinforced concrete not less than 6 in. thick. Such chutes shall be lined with low-duty refractory brick (ASTM C64), not less than 41/'~ in. thick. Equivalent ,construction with walls providing 2-hour fire resistance rating with equivalent structural features shall be acceptable.

3-2.3 Metal Waste Chutes.

3-2.3.1 Metal chutes may be lined with low-duty refractory brick (ASTM C64) not less than 21/~-in. thick or equivalent castable refractories. Unlined steel chutes shall be protected in- ternally by automatic sprinklers (see 3-4. 7).

3-2.3.2 Metal waste chutes shall be ,made of stainless steel or galvanized or aluminum-coated steel with no screws, rivets, or

82-24 INCINERATORS, WASTE AND LINEN HANDLING WASTE CHUTES AND HANDLING SYSTE'MS 82--25

other projections on the interior surface of the chute. Laps or JUll t t~ u c o f ~t u c b i g t I SO t t i t i t tltC llqUl(:l Wilt o r a l n t o ~n e i n -

t e r i o r of the chute. The steel shall not be lighter than as indicated below :

(a) Chutes handling general household or office wastes shall be made of steel not lighter than 16 U.S. gage.

(b) Chutes handling other than general waste, or dense- heavy waste material over 10 pounds per cubic ft., shall be made of steel not lighter than 14 U.S. gage.

3-2.4 Pneumatic Waste Handling Systems.

3-2.4.1 The minimum air velocity in a pneumatic waste handling system shall be not less than 5000 ft. per minute.

3-2.4.2 Risers on pneumatic waste handling systems shall be equipped with. dampers which are open to the atmosphere except when automatically closed to permit a conveying operation in another riser. Immediately after completion of the conveying cycle, all riser dampers shall open automatica.lly.

3-2.4.3 Metal thickness shall be not lighter than 20 U.S. gage steel for material conveying lines, but in all cases shall be of sufficient thickness to retain its design shape under all operating conditions• Charging stations or changes in direction of conveying lines shall be not lighter than 16 U.S. gage steel• Steel shall be galvanized, aluminized or stainless to avoid corrosion.

3-2.424 Pneumatic waste handling systems operating on a dual waste-linen mode shall have • two separate service openings (stations) at each location, one for rubbish and one for linen. These must be sequenced to allow only one charge in the system at ~my given time and must be interlocked electronically to convey material to its proper destination.

3-2.4.5 Dual pneumatic systems which handle other materials in addition to waste shall be designed to operate in the rubbish mode in the event of electrical failure of any of the material diverter switch controls and immediately upon start-up after a scheduled or nonscheduled shut-down of the system.

3-2.4.6 Automatic fire dampers shall be installed at all points where the waste handling system penetrates fire-resistive partitions or floor_assemblies (see Figure 3-2.4.6). The system shall shut down automatically upon closing of one of the fire dampers.

Exception: When the waste handling system penetration of the floor assembly is enclosed by a fir~-rated shaJt both above and below the floor pene-

-tration, a fire damper is not required.

Air " intal~e ~ .

~ ~ Roof

I Ceiling Station front panel H~:] charging doorand 1~ frame assembly Uk II \ 1 1 /2 hour "B; ' I kS t ; label'

' F,t=--,

Fire damper !-" " '

hour °'B" label ~- Ceiling /

Firedamper / " ~ I --i I/Z hour -

"B" label •

2 ~ ~-- ire damg Fire damper 1 1/2 hour - - - - - - - I " " 112 houl "'B'" label

Ceiling

Fire damper typical 1 1/2 To collection "B" label terminal

Typical Staggered Location of Stations Full Pfieumatic Linen and Trash System

Figure 3-2.4.6

t ~ t ~

82-26 INCINERATORS, V~;ASTE AND LINEN HANDLING

Station front pan charging door ant assembly UL 1 1/ "B" label

i

• {

Typical Straight Vertical Drop Full Pneumatic Linen and Trash System

F i g u r e 3-2.4.6 ( C o n t i n u e d )

) collection rminal

WASTE CHUTES AND HANDLING SYSTEMS

3 collection ,rminal

Typical Straight Vertical Drop Gravity and Pneumatic Linen or Trash System

Figure 3-2.4.6 ( C o n t i n u e d )

82-27

• 82-28 I N C I N E R A T O R S ~ArASTE A N D L I N E N H A N D L I N G

3-3 Chute Terminal Rooms.

3-3 .1 Room Criteria. Waste chutes or pneumat ic waste ban- • d l ing systems shall t e rmina te or discharge direct ly i n t o a room

separa ted f~'om other par ts of the bui ld ing by wall, par t i t ion, floor, and floor-ceil ing assembl ies having a fire resistance r a t i n g of not less than 2 hours. ,Openings to such rooms shall be pro tec ted by approved au tomat ic - or self-closing 1 X - h o u r fire doors sui table for Class B openings.

3-3.2 Ven t i l a t i on . Chute te rminal rooms shall have a means Of vent i la t ion to the outdoors under fire cond i t ions . '

3-3.3 A u t o m a t i c S p r i n k l e r s . Au toma t i c sprinklers shall be instal led in chute t e r m i n a l rooms. ~ A short length of hand hose connected to a sui table wate r s u p p l y ' a n d a floor d ra in shall also be provided.

3-3.4 D i s c h a r g e . Rubb i sh chutes or conveying systems shall not discharge direct ly into an incinerator .

3-3.5 Automatic Feeding or Stoking Systems. Systems for the au tomat i c ' transfer of waste mater ia ls f rom a rubbish-chute te rmina l room to an inc inera tor or o ther means of au toma t i c feeding or stoking incinerators shall not be instal led unless special permission of the au thor i ty having jur i sd ic t ion has been., obta ined . 2

3-4 A u t o m a t i c S p r i n k l e r s .

3-4.1 U n l i n e d Metal Chutes. Unl ined meta l g rav i ty - type chutes shall be p rotec, t'ed in terna l ly by au toma t i c sprinklers. This requires a sprinkler at the top of the chute and, in addi t ion, a sprinkler shall be instal led within the chute at a l te rna te floor levels in bui ldings over two stories in height'. See Standard for the Installation of Sprinkler Systems, N F P A 13-1976.

1Fires of the nature likely to occur at chute terminals are generally difficult to control by ordinary means due to the large amount of smoke evolved and consequent difficulty of access by the fire department. Automatic extinguish- ment of such fires in the incipient stage is, therefore, of primary importance.

~There are many situations where arrangements are made for handling refuse meclqanically and automatic stoking of incinerators which would not introduce an unreasonable hazard. In such cases, the authority having jurisdiction may permit such an arrangement, taking into consideration the whole hiyout, its relation to the rest of the building, the presence or absence of complete sprinkler protection, the continuity and competefice of the personal supervision attending the operation, ventilation, access for fire fighting, and similar fac- tors. See also Standard for the Installation of Blower and Exhaust Systems for Dust, Stock, and Vapor Removal or Conveying, NFPA 91-1973.

W A S T E C H U T E S A N D H A N D L I N G S Y S T E M S 82-29

3-4.2 Masonry Waste Chutes. M a s o n r y rubbish chutes con~ J - ~ bnm~ nv~ require au tomat i c sprinklers. JL UI I l l l l J ~ LU

3-4.3 S p r i n k l e r Head Protection. Automa t i c sprinklers shall be instal led in gravi ty waste chutes, or waste hand l ing systems shall be recessed out of. the chute a rea th rough which waste travels. The recessed area shall be so designed as to avoid collection of foreign mattei" in the recessed area.

3-5 Se rv i c e O p e n i n g s .

3-5.1 General Access Gravity-type Waste Chutes.

3-5.1.1 All service openings ' into a waste chute shall be provided with a self-closing, posi t ive-latching, bo t tom-h inged hopper - type , frafiae and fire door assembly appro,¢ed for Class B openings and having a fire pro tec t ion ra t ing of not less than 1 hour. T h e door f rame shall be fastened into the chute and the shaft wall. The design and insta l la t ion shall be such tha t no pa r t of the f rame or door will p ro jec t into . the chute.

3-5.1.2 T h e area of each service opening shall be l imi ted to one- th i rd of the cross-sectional a rea of a square chute and .44 percent of the a rea of a round chute.

3-5.2 Limited Access Gravity-type Waste Chutes.

3-5.2.1 All service openings into a waste chute shall be provided with a gasketed, self-closing, p0si t ive- latching f rame and fire door assembly appr6ved for Class B openings and having a ra t ing of not less than one hour. T h e door f rame shall be fastened into the chute and the shaft wall. T h e design and ins ta l la t ion shall be such tha t no pa r t of the f rame Or door will pro jec t into the chute. A key shall be . r equ i r ed to open the door (see 3-6.3).

3-5.'2.2 T h e a rea of each service opening shall be l imi ted to two-thirds of the cross-sectional a rea of the chute.

3-5.3 Pneumatic Waste Handling Systems.

3-5.3.1 T h e service opening size of pneumat i c waste handl ing systems shal) be designed to provide p rope r en t rance into the system. I t m a y be equiva len t to the cross-sectiofial a rea of the duct or greater .

3-5.3.2 Pneumat i c waste handl ing systems shall be provided wi th a service open ing consisting of two doors, inc luding an au tomat ic - or self-closing, posi t ive- la tching outer door, f ront panel , and f rame assembly, app roved for Class B openings and having a fire ra t ing of not less than 1 hour . The door f rame shall be bui l t

t ~ Ot t ~

82-30 I N C I N E R A T O R S , W A S T E A N D L I N E N H A N D L I N G

firmly into the duct and wall. The system service opening shall be equipped with a second or inner door designed to remain closed at all times under full system pressure unless released by the system control circuit to allow the material placed inside the outer door to enter the duct, provided the outer door is closed. Only one inner service door shall be open during each conveying cycle.

3-5.4 Combined Gravity-Pneumatic Waste Handling Sys- tems.

3-5.4.1 Each section of a gravity-pneumatic system shall conform to the requirements for the individual type of system.

3-5.4.2 The storage area above the metering valve in a gravity-pneumatic system shall be protected by.-automatic sprinklers.

3-6 Service Opening Rooms.

3-6.1 Every service opening shall be enclosed in a room or compartment separated from other parts of the building by wall, partition, floor, and floor-ceiling assemblies having a fire resistance rating of not less than 1 hour.with openings to such room or compartment protected by approved self-closing fire doors suitable for Class B openings.

3-6.2 Service opening rooms shall serve no other purpose and shall not be used for storage of waste or any other materials.

3-6.3 If entrance to a limited access service opening room is gained by a key, the service opening door need not require a key to be opened. One or "the other shall be keyed.

L I N E N C H U T E S OR C O N V E Y O R S 82-31

Chapter 4 Linen (Laundry) Chutes or Conveyors

4-1 General.

4-1.1 Definition." Linen chutes or handlir~g systems are chutes or systems used to transport soiled laundry from the floor or area of collection to a laundry.

4-1.2 Classification. There are three types of linen (laundry) handling systems involving conveyance through a tube or cylinder.

4-1.2.1 Gravity-type Linen Chutes. A gravity-type linen chute of this type is an enclosed vertical passageway in a building where the linen is transferred by gravity to a chute terminal room or collecting facility or a pneumatic system.

4-1.2.2 Pneumatic Linen Handling Systems. A pneumatic linen handling system is a vertical, horizontal, or inclined duct having sufficient mechanically applied air flow to convey linen without clogging to a laundry or collecting facility.

4-1.2.3 A gravity-pneumatic linen handling system is a system using a combination of the types defined in 4-1.2.1 and 4-1.2.2.

4-2 Construction.

4-2.1 General.

4-2.1.1 Linen chutes supported at intervals by the building structure shall be provided with expansion joints between support levels.

4-2.1.2 A linen chute shall extend (full size) at least 4 ft. above the roof of the building. The chute shall be open to the atmosphere.

4-2.1.3 Vertical linen chutes shall be enclosed on all stories above the collection or laundry facility within a continuous enclosure constructed of materials which are noncombustible, and' extending from the ceiling of the collection or laundry room to or through the roof so as to retain the integrity of the fire separations as required by the applicable building code provisions. The walls of the enclosure shall have a fire resistance rating of not less than 1 hour if the building is less than 4 stories in height and not less than 2 hours if the building is 4 or more stories in height.

Exception: Masonry chutes conforming to 3-2.2 or constructed of masonry walls having a fire resistance rating not less than specified above shall not be required to be enclosed.

t ~

82-32 I N C I N E R A T O R S . W A S T E AND L I N E N H A N D L I N G

4-2.1.4 Metal linen chutes or handling" systems shall be

no screws, rivets, or other projections on the interior surface of the chute. Laps or joints shall be of a design so that liquid will drain to the interior of the chute.

4-2.2 Gravity Linen Chutes.

4-2.2.1 The portion of a gravity linen chute located not more than 6 stories below the roof of a building shall be made of steel not lighter than 18 U.S. gage and any other portion shall be made of steel not lighter than 16 .U.S. gage.

• 4-2.2.2 Gravi ty linen chutes shall be constructed straight and plumb with no offsets.

4-2.3 Pneumatic Linen Handling Systems.

4-2.3.1 Metal thicknesses shM1 not be lighter than 20 U.S. gage steel for material conveying lines, but in all cases shall be of sufficient thickness to retain its design shape under all operat ing conditi'ons. Steel shall be galvanized, aluminized or stainless to avoid corrosion.

4-2.3.2 The min imum air velocity in a pneumat ic linen handling system shall be not less than 5,000 ft. per minute.

4-2.3.3 Risers on pneumat ic linen handling systems shall be equipped with dampers which are open to the atmosphere except when automatical ly closed to permit conveying operat ion in another riser. Immedia te ly after completion of the conveying cycle, all riser dampers shall be opened.

4-2.3.4 Pneumat ic linen handling systems operat ing on a dual waste-linen mode shall have two separate service openings (stations) at each location, one for rubbish and. one for linen. These must be sequenced to allow only one charge in the system at any given time and must be interlocked electronically to convey material to its proper destination.

4-2.3.5 Dual pneumat ic systems which handle other materials•(such as waste) in addition to linen (laundry) shall be designed to operate in the waste mode in the event of electrical failure of any of the material diverter switch controls and immediately upon start-up after a scheduled or nonscheduled shutdown of the system.

4-2.3.6 Automat ic fire dampers shall be installed at all p0ints where the linen handling system penetrates fire-resistive par-

L I N E N C H U T E S OR C O N V E Y O R S 82-33

titions or floor assemblies (see Figure 3-2.4. 6). The system shall shut down autumaticai ly upon closing of one of the fire dampers.

Exception: When the linen handling system penetration of the floor assembly is enclosed by a fire-rated shaft both above and below the floor penetration, a fire damper is not required.

4-3 Chute Terminal Rooms.

4-3.1 Linen (laundry) chutes or pneumat ic linen hand l ing systems shall terminate or discharge directly into a room separated from other parts of the building by wall, partition, floor, and floor- ceiling assemblies having a 2-hour fire resistance rating. Openings to such rooms shall be protected by approved automatic- or self- closing 1 ]~-hour fire doors suitable for Class B openings.

4-3.2 Automat ic sprinklers shall be installed in chute terminal rooms. A short . length of hand hose connected to a suitable water supply and a floor drain shall also be provided.

4-4 Automatic Sprinklers.

4-4.1 Metal Gravity-type Chutes. Metal gravity-type chutes ~h~ll l..~ protected :~* . . . . "- ~"" . , ~u . ,~ . y by automat ic ..... : - ' '- ~ms o , x a a x u u b l . ) l l l l K l g l ~ S , r e -

quires a sprinkler at the top of the chute and, in addition, a sprinkler shall be installed within the chute at alternate floor levels in buildings over two stories in height. See Standard.for the Installation of Sprinkler Systems, N F P A 13-1976.

4-4.2 Chute Terminal Rooms. The room or area into which a chute or linen handling system discharges shall be protected with automatic sprinklers.

4-4.3 Sprinkler Head Protection. Automat ic sprinklers installed in linen chutes or linen handling systems shall be recessed out of the chute area through which linen travels. T h e recessed area shall be so designed as to avoid collection of foreign matter in the recessed area.

4-5 Service Openings.

4-5.1 Gravity-type Linen Chutes.

4-5.1.1 All service openings into a linen chute shall be provided with a gasketed, self-closing, positive-latching frame and fire door assembly approved for Class B openings and having a

• rating of not less than one hour. The door f rame shall be firmly built into the chute and the design and installation shall be such that no par t of the frame or door will project into the chute.. A kev shall be required to open the door (see d-6.3).

82-34 iNCINERATORS, WASTE AND LINEN HANDLING

4-5.1.2 The area of each service opening shall not exceed the cross-sectional area of the chute.

4-5.2 Pneumatic Linen (Laundry) Handling Systems.

4-5.2.1 The service opening size of pneumatic linen handling systems shall be designed to provide proper entrance into the system. I t may be equivalent to the cross-sectional area of the duct or greater. The maximum door width shall be not greater than the duct diameter.

4-5.2.2 Pneumatic linen handling systems shall be provided with a service opening consisting of two doors,, including an automatic- or self-closing, positive-latching outer door, front panel, and frame assembly, approved for Class B openings and having a fire rating of not less than. one hour. The door frame shall be built firmly into the duct and wall. The system service opening shall be equipped with a second or inner door designed to remain closed at all times under full system pressure unless released by the system control circuit to allow the material placed inside the outer door to enter the duct provided the outer door is closed. Only one inner service door shall be open during each conveying cycle.

4-5.3 Combination Gravity-Pneumatic Linen Handling System s .

4-5.3.1 Each section of a gravity-pneumatic system shall conform to the requirements for the individual type of system.

4-5.3.2 The storage area above the metering valve in a gravity-pneumatic system sKall be protected by automatic sprinklers.

4-6. Service Opening Rooms.

4-6.1 Every service opening shall be enclosed in a room or compartment separated from other parts of the building by wall, partition, floor, and floor-ceiling assemblies having a fire resistance rating of not less than 1 hour with openings to such room or compartment protected by approved self-closing fire doors suitable for Class B openings.

4-6.2 Service opening rooms shall serve n o other purpose and shall not be used .for storage of waste" or any other materials.

WASTE COMPACTORS 82--35

Chapter 5 Waste Compactors

5-1 General.

5-1.1 Definition. Waste compactors are devices using electro- mechanical-hydraulic means to reduce the volume of waste and to package it in the reduced condition.

5-1.2 Classification. The two types of compactors regulated by the provisions of this standard are as follows:

5-1.2.1 Domestic compactors are designed for use in dwellings or individual dwelling units for compaction of family de- veloped waste.

5-1.2.2 Commercial-industrial compactors are designed for use in multiple family or other classes of occupancies. They may be located indoors or outdoors. They c~/n be chute fed or hand fed. Discharge of the compactor may be into metal-compaction containers or disposable packages.

5-2 Domestic Compactors.

5-2.1 Domestic compactors shall be so designed that the unit can be opened manually in the event of electrical failure.

5-2.2 The compacting chamber shall be so designed as to be enclosed on all sides, top, front and bottom with steel construction that will contain fire in the event of waste ignition.

5-3 Commercial-Industrial Compactors.

5-3.1 All chute-fed compactors shall h a v e an automatic special fine water spray sprinkler head with a minimum l~-in. orifice installed in the hopper of the compactor. This sprinkler shall activate when -the temperature within the hopper of the compactor rises above 165°F, and shall not turn itself off until the

• temperature in the hopper of the compactor has been reduced by at least 10°F. The sprinkler shall be supplied by a minimum of a },~-in. line from the nearest domestic cold water. The sprinkler head shall provide a suitable spray into the hopper. An on-off, self- actuating, snap-action, heat-actuated sprinkler may be used, or the sprinkler may be controlled by a temperature sensor operating a solenoid valve. Sprinkler water piping shall be protected from freez- ing in outdoor installations.

W

82-36 . INCINERATORS, WASTE AND LINEN HANDLING.

5-3.2 Hand-fed compactors located within a building and not operated in conjunction with a .chute do not require installation of an automatic sprinkler in the hopper. Compactors larger than 2 cubic yards shall be enclosed in a fire-rated room in con- formance with 5-3.4.

5-3.3 Refuse compaction containers shall have an access door to the container located fidar the top without requiring dis- connecting of the container from the compactor or shall be provided with one 21/~-in. hose connection fitting standard fire fighting equipment near the top of the container.

5-3.4 Chute terminal, cor~pacting, or storage rooms shall be separated from other parts of the building by wall, partition, floor ~ind floor-ceiling assemblies having a fire resistance rating of not less than. 2 hours. Openings to such rooms shall be protected by approved automatic- or self-closing fire doors suitable for Class B openings.

WASTE STORAGE ROOMS 82-37

Chapter 6 Waste Stoiage Rooms

6-1 Waste storage rooms in a building or structure shall comply with specifiedrequirements for a waste storage room if it is used for the keeping, storage, or handling of waste that is loose, baled, or compacted or in containers in an amount exceeding three cubic yards (uncompacted measure).

6-2 Waste storage rooms shall be separated from other parts of the building by-walls and floor and ceiling assemblies, having a fire resistance rating of not less than 2 hours. Openings to such rooms shall be protected by approved automatic- or self-closing fire doors suitable for Class B openings.

6-3 Waste • storage rooms shall be proyided ..with automatic, sprinklers installed in accordance with the Standard for the Installa- tion of AiLtomatic Sprinkler Systems, NFPA 13-1976. A short length of hand hose" connected to a suitable water source and a suitable floor drain shall also be provided.

82-38

Q

INCINERATORS~ WASTE AND LINEN HANDLING

Chapter 7 Waste Receptacles

7-1 Classification. The two types of receptacles considered in this standard are:

(a) Receptacles intended for sustained outside storage (more than 24 hours) for waste paper and other similar materials.

(b) Receptacles for temporary indoor storage (up to 24 hours) of waste paper and other similar materials.

7-2 Receptacles for Sustained Storage.

7-2.1 Construction receptacles for sustained storage shall be of noncombustible material and shall be equipped with a tight- fitting cover. They shall be provided with a flange or wheels at the bottom to provide at least a 2-in. air space between the bottom and the floor. They shall resist water , have no cracks, holes or jagged edges, and shall be nonabsorbent.

7-3 Receptacles for Temporary Storage.

7-3.1 All temporary storage receptacles shall be listed.

7-3.2 Receptacles must be able to contain burning paper and to withstand small external fires without melting or contributing fuel to the fire.

7-3.3 Receptacles shall be free from defects which may im- pair their serviceability or safety characteristics.

7-3.4 Receptacles shall be fabricated of material having the strength necessary to withstand abuses liable to be encountered in service.

7-3.5 Construction. Receptacles for temporary storage shall have tight-fitting lids and be constructed to have no cracks, holes or jagged edges and be nonabsorbent.

They shall be smooth, without interior projections or rough seams which will make it difficult to clean or interfere with its emptying. They shall not exceed a volume of 7 cubic feet.

7-3.6 Storage. Temporary storage receptacles shall be stored within a fire-rated storage room with the maximum uncom- pat ted storage in any given room not greater than 3 cubic yards. Storage rooms shall be separated from other parts of the building by walls and floors and ceiling assemblies having a 2-hour fire resistance rating. Openings to such rooms shall be protected by approved automatic- or self-closing 1 K-hour fire doors suitable for Class B openings.

APPENDIX A 82- -39

Appendix- A Referenced Publications

This Appendix 48 not a part of this N F P A Standard on Incinerators, Waste and Linsn Handl ing Systems and Equipment, N F P A 8~-1977, but is included for information purposes only

A-1 NFPA Standards. This publication makes reference to the following NFPA codes and standards and the year dates shown indicate the latest editions available. All these publications may be obtained by ordering them from the Publications Department, National Fire Protection Association, 470 Atlantic Avenue, Boston, MA 02210.

(a) NFPA 13-1976, Standard for the Installation of Sprinkler Systems (b) NFPA 31-1974, Standard for the Installation of Oil Burning

Equipment (c) NFPA 54-1974, Naiional Fuel Gas Code (d) NFPA 70-1975, National Electrical Code (e) NFPA 90A-1976, Standard for the Installatio~i of Air Conditioning

and Ventilating Systems (f) NFPA 91-1973, Standard for the Installation of Blower and

Exhaust Systems for Dust, Stock, and Vapor Removal or Conveying (g) NFPA 97M-1972, Standard Glossary o f Terms Relating to

Chimneys, Vents, and Heat Producing Appliances (h) NFPA 211-1972, Standard for Chimneys, Fireplaces, and Vents

A-2 Other Codes and Standards. This publication makes reference to the following codes and standards and the year dates shown indicate the latest editions available.

(a) ASTM A167-1974, Specifications for Stainless and Heat- Resisting Chromium-Nickel Steel Plate, Sheet, and Strip, American So- ciety for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103

(b) ASTM A478-1970, Specifications for Chromium-Nickel Stainless and Heat-Resisting Steel Weaving Wire, American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103

(c) ASTM C64-1972, Specifications for Refractories for Incinerators and Boilers, American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103

(d) ASTM C105-1971, Specifications .for Ground Fire Clay as a. Refractory Mortar for Laying-Up Fireclay Brick, American Society for Testing and Materials, 1916 Race Street, Philadelphia, Penn- sylvania 19103

GENERAL 211-5

Part II . S t a n d a r d f o r

Chimneys, Fireplaces, and Vents NFPA 2 1 1 - - 1 9 7 7

Chapter 1 General

1-1 Scope. This edition of NFPA 211 represents basic standards for chimneys, fireplaces, and venting systems, their safe installation.and use. The standard applies to residential as well as commercial, and industrial applications.

1-2 Purpose. .1-2.1 All fuel-burning appliances, including fireplaces, pro-

duce products of combustion (waste gases) when in use. These waste gases must be safely and completely expelled to the ou t s ide atmosphere. The safe removal of these waste gases, the firesafe

construct ion and installation of chimneys, fireplaces, and ven t ing systems for residential, commercial, and industrial appliances are the pr imary concern of this standard.

1-2.2 Selection of a chimney or vent is dependent on the type of appliance connected thereto, the fuel used by the appliance and the temperature of the flue gases at the appliance outlet. 'This standard gives minimum construction and installation requirements.for chimneys and vents suitable for use with appliances classified as residential type, building heating, low, medium and high heat appliances: Appendix' A covers the selection of a chimney for various appliances. Appendix B covers the selection of a v e n t for certain appliances listed as suitable for use with such vents.

1-3 Definitions. 1-3.1 Combustible Material. Material made of or surfaced

with wood, compressed paper, plant fibers, plastics, or other material that will ignite and burn, whether flameproofed or not, or whether plastered or unplastered.

1-3.2. Noncombust ib le Material . Material which will not ignite and bui'n, such materials consisting entirely of steel, iron, brick, tile, concrete, slate, asbestos, glass or plasters, or combination thereof.

1-3.3 Other definitions relating to chimneys, fireplaces, and venting systems are contained in the Glossary. of Terms Relating tO Heat Producing Appliances, NFPA 97M-1972.

211-6 CHIMNEYS, FIREPLACES, AND VENTS

Chapter 2 Draft, Termination, Factory-built Chimney Units and Liners

2-1 Draft. 2-1.1 A chimney or vent shall be capable' of producing a

draft at the appliance not less than that' required for safe operation • of the appliance(s) connected thereto in accordance with Chapter 26,

Chimney, Gas Vent, and Fireplace Systems, of the 1975 Equipment Volume of the ASHRAE Handbook.

2-1.2 A mechanical draft system of either forced or induced draft design may be used to increase draft or capacity. When a mechanical draft system is installed, provision shall be made to prevent the flow of fuel to automatically fired appliance(s) when that system is not operating.

2-1.3 Chimneys serving incinerators, or other process equipment where the combustion process cannot be completely Stopped by fuel shutoff alone, shall be sized for natural draft conditions. When air pollution control devices, or other devices, in the chimney system require a mechanical draft system, the chimney system shall be so arranged that upon a power failure the natural draft chimney alone "can satisfactorily remove the products of combustion until the combustible material is completely consumed.

2-1.4 Forced draft systems and all portions of induced draft systems .under positive pressure during operation shall be designed and installed so as to be gastight or as to prevent leakage of combustion products into a building.

2-2 Termination (height). 2-2.1 Chimneys and vents shall terminate above the roof level

in accordance with the requirements of this standard. (See also Appendix D.)

Exception: As provided in 4-2. I Exception, 6-3~ and 6-6.

2-2.2 Na.tural draft chimneys and.vents shall not terminate at an elevation less than 5 ft. (1.53 m) above the flue collar or highest connected draft hood outlet.

Exception: As provided in 6-6.

2-3 Factory-built Chimneys and Chimney Units. 2-3.1 Factory-built chimneys and chimney units shall be listed,

and shall be installed in accordance with the temperature conditions of the listirig and the manufacturer 's instructions. Flue gas temperatures in the Chimney shall not exceed the limits employed during listing tests.

FACTORY-BUILT CHIMNEYS AND LINERS 211-7

2-3.2 Factory-built chimneys may be used for exhaust sys- .terns and ducting from hoods, industrial ovens, furnaces and process equipment of any temperature classification (see Appendix A) provided that the system is engineered so that gas temperatures and pressures do not exceed the applicable limit for the type of chimney.

2-3.3 Factory-built chimneys which pass through floors of buildings requiring the protection of vertical openings shall be enclosed with approved walls having a fire resistance rating of not less than 1 hour when such chimneys are located in a building less than 4 stories in height, and not less than 2 hours when such _chimneys are located in a building 4 stories or more in height.

2-4 Flue Lining.

2-4.1 Castable or plastic refractories 'used to line chimneys or connectors shall be the equivalent in resistance to heat and erosion by flue gases to that of the firebrick which would otherwise be specified.

2-4.2 Lining made of castable or plastic refractories 'shall be secured to the supporting walls by anchors made of corrosion resistant steel capable of supporting the refractory load at 1500°F (816°C).

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211-8 C H I M N E Y S , F I R E P L A C E S , AND V E N T S "

Chapter 3 Masonry Chimneys

3-1 General Requirements.

3-1.1 Support . Masonry chimneys shall be supported' on properly designed foundations of masonry or reinforced portland or refractory cement concrete, or on noncombustible material having a fire resistance rating of not less than 3 hours provided such supports are independent of the buildin~ construction and the load is transferred to the ground.

3-1.2 Corbeling.

3-1.2.1 Mason@ chimneys shall not be corbeled f rom a wall more than 6 inches (152 ram).

3-1.2.2 Masonry chimneys shall not be corbeled from a Wall which is less than 12 inches (305 mm) in thickness.

Exception: When it projects equally on each side of the wall plovided that in the second story of two-story dwellings corbeling of chimneys on the exterior of the enclosing walls may equal the wall thickness.

3-1.2.3 Corbeling shall not exceed one-inch (25.4-mm) pro- jection for each course of brick projected.

3-1.3 Change in Size or Shape at Roof Not Permitted. A change in the size or shape of a chimney flue where the chimney passes through the roof shall not be made within a distance of 6 inches (152 mm) above or below the roof joists or rafters.

3-1.4 Cleanout Openings. Cleanout openings provided--in chimneys shall be equipped with ferrous metal doors and frames arranged to remain tightly closed when not in use.

3 -1 .5 Firestopping. All spaces between chimneys and floors and ceilings through which chimneys pass shall be firestopped with noncombustible material. The firest6pping of spaces between chimneys and wood joists, beams, or headers shall be to a depth of one inch (25.4 ram) only placed on strips.of metal or metal lath laid across the spaces between combustible material and the chimney.

3-1.6 Smoke Test. Masonry chimneys shall be proved tight by a smoke test after erection and before being put into use.

3-2 Masonry Chimneys for Residential-type Appliances. (See Appendix A.)

3-2.1 Construction.

MASONRY C H I M N E Y S 211-9

3-2.1.1 Masonry chimneys for residential-type appliances shall be constructed of solid masonry units or reinforced portland OF l 'C l l ' i tCtu ly ~5~ixtcllt ~OfiC~CLC ...'+I~ . . . . llo n ~ t loee t ~ n ~ ino~eq

(102 mm) thick or rubble stone masonry not less than 12 inches (305 "ram) thick. Masonry shall be laid with full, push-fil!ed, cross and bed, mortar joints.

3-2.1.2 Masonry chimneys for residential-type appliances shall be lined with fire-clay flue lining (ASTM C315) or the equivalent not less than 5~ of an inch (16 mm) thick, or with liner of other approved material that will resist corrosion, softening or cracking from flue gases at temperatures up to 1800°F (982°C).

3-2.1.3 Fire-clay flue liner shall be installed ahead of the construction of the chimney as it 'is carried up, carefully bedded one on the other in refractory mortar (ASTM C105, medium duty) or the equivalent, with close fitting joints left smooth on the inside.

3-2.1.4 Lining shall be separate from the chimney whll and the space between the liner and masonry shall not be filled; only enough mortar shall be used to make a good joint and hold the liners in position.

3-2.1.5 Flue lining shall start f rom a point not less than 8 inches /~n~ ram) below *h- 1~, .... ~ t rhimney cnnneetor entrance. The lining shall extend, as nearly vertically as possible, for the entire height of the chimney.

3-2.1.6 Where two adjoining flues in the same chimney are separated only by flue liners the joints of the adjacent flue liners shall be staggered at least 7 inches (178 mm).

3-2.1.7 Where more than two flues are located in the same chimney, masonry wythes (partitions) at least 4 inches (102 mm) wide and bonded into the masonry walls of the chimney shall be built at such points between adjacent flue linings that there are not more than two flues in any group of adjoining flues without such wythe separation.

3-2.2 Te rmina t ion (height). Masonry chimneys for residential-type appliances shall extend at least 3 feet (.92 m) above the highest point where they pass through the roof of a building and at least 2 feet (.61 m) higher than any portion of a building within 10 feet (3.1 m). (See Appendix D.)

3-2.3 Clearance from Combustible Material.

3-2.3.1 All wood beams, joists and studs shall be t r immed away from chimneys. Headers, beams, joists and studs shall be not

t ~

211-10 CHIMNEYS) FIREPLACES, AND VENTS

less than 2 inches (51 mm) from the outside face of a chimney or from masonry enclosing a flue. ,

Exceptz'on: Ends of wood girders may be supported on a corbeled shelf of a masonry chimney provided there is not less than 8 inches (203 mm) of solid masonry between the ends and the flue liner.

3-2.3.2 Combustible lathing, furring, or plaster grounds shall not be placed against a chimney at any point more than 11/~ inches (38 mm) from the corner of the chimney.

Exception No. 7: This requirement shall not prevent plastering directly on the masonry or on metal lath and metal furring.

Exception No. 2: This requirement shall not prevent placing chimneys for residential-type appliances entirely on the exterior of a building against the sheathing.

3-3 Masonry Chimneys for Low Heat Appliances.

3-3.1 Construction.

3-3.1.1 Masonry chimneys for low heat appliances shall be constructed of solid masonry units or reinforced portland or refractory cement concrete with walls not less than 8 inches (203 mm) thick or rubble stone masonry not less than 12 inches (305 ram) thick. Masonry shall be laid with full, push-filled, cross and bed, mortar joints.

3-3.1.2 Masonry chimneys for low heat appliances shall be lined with fire-clay flue lining (ASTM C315), or the equivalent, not less than % of an inch (16 ram) thick, or with liner of other approved material that will resist erosion, softening or cracking from flue gases at temperatures up to 1800°F (982°C).

3-3.1.3 Fire-clay flue liners shall be installed ahead of the construction of the chimney as it is carried up, carefully bedded one on the other in refractory mortar (ASTM C105, medium duty) or the equivalent, with close fitting joints left smooth on the inside.

3-3.1.4 Flue liners shall start f rom a point not less than 8 inches (203 ram) below the lowest chimney connector entrance. The lining shall extend, as nearly vertically as possible, for the entire height of the chimney.

3-3.1.5 Where two adjoining flues in the same chimney are separated only by flue liners, the joints of ' the adjacent flue liners shall be staggered at least 7 inches (178 mm).

MASONRY CHIMNEYS 211-11

3-3.1.6 Where more than two flues are located in the same chimney, masonry wythes (partitions) at least 4 inches (102 mm) wide and bonded into the masonry walls of the chimney shall be built at such points between adjacent flue linings that there are not more than two flues in any group of adjoining flues without such wythe separation.

3-3.2 Termination (height). Masonry chimneys for low- heat appliances shall extend at least 3 feet (.92 m) above the highest point where they pass through the roof of a building and at least 2 feet (.61 m) higher than any portion of a building within 10 feet (3.1 m). (See Appendix D.)

3-3.3 Clearance from Combustible Material.

3-3.3.1 All wood beams, joists and studs shall be tr immed away from chimneys. Headers, beams, joists and studs shall be not less than 2 inches (51 ram) f rom the outside face of a chimney or from masonry enclosing a flue.

3-3.3.2 Combustible lathing, furring, or plaster grounds shall not be placed against a chimney at any point more than 11~ inches (38 mm) from the corner of the chimney.

Exception No. 1: This requirement shall not prevent plastering directly on the masonry or on metal lath and metal furring.

Exception No. 2: This requirement shall not prevent placing chimneys for low heat appliances entirely on the exterior of a building against the sheathing.

3-4 Masonry Chimneys for Medium Heat Appliances.

3-4.1 Construction.

3-4.1.1 Masonry chimneys for medium heat appliances shall be constructed of solid masonry units or of reinforced portland or refractory cement concrete with walls not less than 8 inches (203 mm) thick or with stone masonry not less than 12 inches (305 ram) thick.

3-4.1.2 Masonry chimneys for medium heat appliances shall be lined with medium-duty fire brick (ASTM C64, Type F) or the equivalent, not less than 4 ~ inches (114 ram) thick laid on the 4 ~ - i n c h (114-mm) bed in refractory m o r t a r (ASTM C105, medium duty) or the equivalent.

3-4.1.3 The flue lining shall start 2 feet (.61 m) or more below the lowest chimney connector entrance and shall extend to a height of at least 25 feet (7.63 m) above the highest chimney connector entrance. Chimneys terminating 25 feet (7.63 m) or less above a chimney connector entrance shall be lined to the top.

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211-12 C H I M N E Y S , F I R E P L A C E S , A N D V E N T S '

3-4.2 Terminat ion (height). Masonry chimneys for medium heat appliances shall extend not less than 10 feet (3.1 m) higher than

UI rely puluon any uunomg within z~.ieet (7.63 m).

3-4.3 Clearance from Combustible Material. A clearance of not less than 4 inches (102 mm) shall be provided between the exterior surfaces of a masonry chimney for medium heat appliances and combustible material.

3-5 Masonry Chimneys for High Heat Appliances.

3-5.1 Construction.

3-5.1.1 Masonry chimneys for high heat appliances shall be constructed with double walls of solid masonry units or reinforced portland or refractory cement concrete, each wall to be not less than 8 inches (203 ram) thick with an air s]3ace of not tess than 2 inches (51 ram) between them.

3-5.i.2 The inside of the interior wall of masonry chimneys for medium heat appliances shall be lined with high-du W fire brick (ASTM C64, Type A) or the equivalent, not less than 41/~ inches (114 ram) thick laid on the 41/6-inch ( l l4-mm) bed in refractory mortar (ASTM C105, high duty) or tile equivalent.

' 3-5.1.3 The lining shall start at the base of the chimney and extend continuously to the top.

.3-5.2 Terminat ion (height). Masonry" chimneys .for high heat appliances shall extend not less than 20 feet (6.1 m) higher than any portion of any building within 50 feet (15.3 m).

3-5.3 Clearance from Combustible Material. Masonry chimneys for high heat appliances shall have sufficient clearance f rom buildings and structures to avoid overheating combustible material, to permit inspection, maintenance operations on the chimney and to avoid danger of burns to persons. Clearances shall be based on good engineering practice and acceptable to the authority having jurisdiction.

3-6 Masonry Chimneys for Incinerators..

3-6.1 Residential. Masonry chimneys for residential~.ype incinerators shall be constructed in accordance with the reqmre- ments for Chimneys for Residential Type Appliances, Section 3-2.

3-6.2 Chute-fed Incinerators. See Standard on Incinerators and Rubbish Handlzng, NFPA 82~-1972.

\ l

M A S O N R Y C H I M N E Y S 211-13

3-6.3 Commercial and Industrial-type Incinerators. ' 2_~ '2 I t " ~ ^~ .~- . . . . 4 . ' __

v , ~ . ~ ~ v a a o l . a L~bgzU/.a

3-6.3.1.1 Masonry chimneys for commercial and industrial incinerators shall be constructed of solid masonry units or reinforced portland or refractory cement concrete with walls not less than 8 inches (203 ram) thick.

3-6.3.1.2 Masonry chimneys for commercial and industrial incinerators shall be lined with medium-duty fire bi-ick (ASTM C64, Type F) or the equivalent, not less than 41/~ inches (114 ram) thick laid on the 41/~-inch (114-mm) bed in refractory mortar (ASTM C105, medium duty) or the equivalent.

3-6.3.1.3 The lining shall start at the base of the chimney and extend continuously to the top.

5-6.5.1.4 Masonry chimneys for •commercial a n d industrial incinerators shall be supported on properly designed foundations of masonry or reinforced portland or refractory cement concrete or on noncombustible material having a fire resistance rating of not less than 3 hours provided such supports' are independent of the building construction and the load is transferred to the ground.

Exception: Chimneys may be supported on incinerator walls i f the incinerator foundation and walls are built to support the load thus imposed. They shall be so constructed as not to place excessive stress upon the roof of the combustion chamber.

3-6.3.2 Te rmina t ion (he igh t ) .

3-6.3.2.1 Masonry chimneys for commercial and indu~- trial incinerators shall extend not less than 10 feet (3.1 m) higher ' than any portion of any building within 25 feet (7.63 m).

3-6.3.2.2 The terminus of the chimney flue for the incinerator shall be equipped with an approved spark arrester if the incinerator does not include effective means for arresting sparks and fly ash. (See N F P A 82-1972.)

3-6.3.3 Clearances. A clearance of not less than 4 inches (102 mm) shall be provided between the exterior surface of masonl-y chimneys for commercial and industrial-type incinerators and combustible materials.

ho

211-14 CHIMNEYS~ FIREPLACES~ AND VENTS

Chapter 4 Metal Chimndys (Smokestacks)

4-1 General Requirements .

4-1.1 Single-wall metal chimneys or unlisted metal chimneys shall not be used inside one- and two-family dwellings.

4-1.2 Metal chimneys shall be constructed of steel or cast iron. Sheet steel shall have a thickness not less than that indicated in Table 4-1.2.

Table 4-1.2 Minimum Thickness of Sheet Steel Chimneys

Min." ! Equiv. Round Mfgr. Std. Thickness i Area Diam. Gage No. inch (mm) i in2/m ~ inch/mm

I 16 .054 (1.37) 1 up to 154/.0994 up to 14/356 14 .069 (1.75) I 155/.0999 to 201/.1296 over 14/356 to 16/406 12 .098 (2.49) 202/.1303 to'254/.1638 over 16/406 to 18/457 10 .128 (3.25) Larger than 254/.1638 over 18/457

NOTE: Regardless of minimums in this table, the thickness of sheet metal shall be adequate to meet the requirements of 4-1.3.

4-1.3 Metal chimneys "shall be properly riveted, welded or bolted, securely supported and constructed in accordance with good engineering practice as necessary for the following:

(a) Strength to resist stresses due to steady or gusting wind loads.

(b) Adequate anchoring, bracing, and inherent strength to withstand seismic and wind-induced vibrational stresses.

(c) Proper material thickness for durability considering fuel analysis, gas temperature, and exposure.

(d) Security against leakage of flue gases under positive pressure.

(e) Allowance for thermal expansion of breeching and vertical sections.

4-1.4 Metal chimneys shall not be used inside of ventilating ducts.

Exception: When such ducts are constructed and installed as required by this standard for chimneys and the ventilating ducts are used solely.for exhaust of air.from the room or space in which the appliance served by the metal chimney is located.

METAL CHIMNEYS (SMOKESTACKS) 211-15

4-1.5 Metal chimneys shall have sufficient, clearance from buildings and structures to avoid heating combustible material to a temperature in excess Of 180°F (82.2°C) and to permit inspection and maintenance operations on the chimney. They shall be located or shielded to avoid danger of burns to persons.

4-1.6 Metal chimneys shall be supported on properly designed foundations of masonry or reinforced portland or refractory cement concrete or, on noncombustible material having a fire resistance rating of not less than 3 hours provided such supports are independent of the building construction and the load is transferred to the ground.

A factory-built chimney, if so listed, and a metal chimney may be supported also at intervals by the building structure, in which case, expansion joints shall be provided at each support level. All joints shall be liquid tight or of a design such that liquid will drain to the interior of the Chimney.

4-1.7 Metal chimneys serving residential-type or low heat appliances and producing flue gases having a temperature below 350°F (165.5°C) at the entrance to the chimney at full load or partial load shall be lined with acid and condensate resistant metal or refractory material, or constructed of suitable stainless steel, or otherwise protected so as to minimize or prevent condensation and corrosion damage. /

4-2 Metal Chimneys for Resident ia l - type or Low Heat Appliances.

4-2.1 Terminat ion (height) . Metal chimneys for residential- type or low heat appliances shall extend at least 3 feet (.92 m) above the highest point where they pass through the roof of a building and at least 2 feet (.61 m) higher than any portion of a building within 10 feet (3.1 m). (See Appendix D.)

Exception: The outlet of a metal chimney.for residential-type and low heat appliances equipped with an exhauster may terminate at a location not less than 3-feet (.92 m) from an adjacent building or building opening and at least lOJeet (3. 1 m) above grade or walkways. In any case, the outlet shall be so arranged that the flue gases are not directed so as to jeopardize people, overheat combustible structures, or enter building openings in the vicinity o-f the outlet.

4-2.2 Clearances.

4-2.2.1 Exterior.

t ~


4-2.2.1.1 Exterior metal chimneys used only for residential-type or low heat appliances as defined in Appendix A shall have a clearance of not less than '6 inches (152.4'mm) from a wall of wood f rame construction and from any combustible materiai.

4-2.2.1.2 Exterior metal chimneys over 18 inches (457 ram) in diameter shall have a clearance of not less than 4 inches (102 mm) from a building wall of other than wood frame construction.

4-2.2.1.3 Exterior metal chimneys.18 inches (457 ram) or less in diameter shall have a clearance of not less than 2 inches (51 mm) from a'building wall of other than wood frame construction.

4-2.2.1.4 A metal chimney erected on the extei-ior of a building shall not be installed nearer than 24 inches (610 mm) to any door or window or to any walkway.

Exception: The distance may be less than 24 inches (610 ram) when the chimney is insulated in an approved manner to avoid danger of burns to persons .

4-2.2.2 Interior.

4-2.2.2.1 Where a metal chimney extends through any story of a' building above that in which the appliances connected to the chimney are installed, it shall be enclosed in such upper stories, within a continuous enclosure constructed of noncombustible materials (see Section 1-3.2). The enclosure shall comply with the following:

(a) Tile enclosure shall extend" from the ceiling of the appliance room to or through the roof so as to maintain the integrity of the fire separations required by the applicable building code provisions. "

(b) The enclosure walls shall have a fire resistance rating of not less than 1 hour if the building is less than 4 stories in height.

(c) The enclosure walls shall have a fire resistance rating of not less than 2 hours if the building is 4 stories or more in height.

(d) The enclosure shall provide a space on all sides of the chimney sufficient to permit inspection and repair, but in no case shall it be less than 12 inches (305 mm).

(e) The enclosing walls shall be without openings.

Exception: Doorways equipped with approved self-closing fire doors, may be installed at various floor levels for inspection purposes..

4-2.2.2.2 Where a metal chimney serving only residential- type or low heat appliances as defined in Appendix A is located in

METAL CHIMNEYS (SMOKESTACKS)

. /

211-17

the sam e story of a building as that in which the appliances con- n e o t e r l t h e r e t o ~ r ~ l o r ~ t ~ c t i t rh'~11 h ~ w P ~ r l ~ r ~ t ~ r ~ n f n,~t l P ~ tF ,~n

18 inches (457 mm) from a wall of wood frame consti'uctiofi and from any combustible material.

4-2.2.2.3 Interior metal chimneys over 18 inches (457 mm) in diameter shall have a clearance of not less than 4 inches (102 mm) from a building wall of other than wood frame construction.

4-2.2.2.4 Interior metal chimneys 18 inches (457 ram) or less in diameter shall have a clearance of not less than 2 inches (51 mm) from a building wall of other than wood frame construction.

• 4-2.2.2.5 Where a metal chimney.serving only residential- type or low heat appliances as defined in Appendix A passes through a roof constructed of combustible material, it shall be guarded by a ventilating thimble of galvanized iron or approved corrosion resistant metal, extending not less than 9" inches (229 ram) below and 9 inches (229 ram) above the roof construction, and of a size to

provide not less than 6 inches (152 mm) clearance on all sides of the chimney.

Exception: In lieu of the above requirement, the combustible material "in the roof construction may be cut away so as to provide not less than 18 inch'es (457 ram) clearance on all sides'of the chimney, with any material used to close up such opening entirely noncombustible.

4-3 Metal Chimneys for M e d i u m Heat Appliances.

4-3.1 Construction. Metal chimneys serving medium heat appliances as defined in Appendix A shall be lined with medium- duty fire brick (ASTM C64, Type F) or the equivalent laid in fire- clay mortar (ASTM C105, medium duty), or the equivalent.

4-3.1.1 The lining shall be at least 21~ inches (64 ram) -thick for 'chimneys having a d iamete r or greatest cross-section dimension of 18 inches (457 mm) or less.

4-3.1.2 The lining shall have a thickness of not less than 41/~ inches (114 mm) laid on the 41/~-inch (114-mm) bed for chimneys having a diameter or greatest cross-section dimension greater than 18 inches (457 mm).

4-3.1.3 The lining shall start 2 feet (.61 m) or more below the lowest chimney connector entrance and shall extend to a height of at least 25 feet (7.6 m) above the highest chimney "connector entrance. Chimneys terminating 25 feet (7.6 m), or less above a chimney connector entrance shall be lined to the top.

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211-18 CHIMNEYS~ FIREPLACES~ AND VENTS

4-3.2 Termina t ion (height). Metal chimneys for medium heat appliances shall extend not less than 10 feet (3.1 m) higher than any portion of any building within 25 feet (7.6 m).

4-3.3 Clearances.

4-3.3.1 Exterior.

4-3.3.1.1 Exterior metal chimneys used for medium heat appliances as defined in Appendix A shall have a clearance of not less than 24 inches (610 mm) from a wall of wood frame construction and from any combustible material.

4-3.3.1.2 Exterior metal chimneys over 18 inches (457 mm) in diameter shall have a clearance of not less than 4 inches (102 mm) from a building wall of other than wood frame construction.

4-3.3.1.3 Exterior metal chimneys 18 inches (457 mm) or less in diameter shall have a clearance of not less than 2 inches (51 ram) from a building wall of other than wood frame construction.

4-3.3.1.4 A metal chimney erected on the exterior of a building shall not be installed nearer than 24 inches (610 mm) to any door or window or to any walkway.

Exception: The distance may be less than 24 inches (610 ram) when the chimney is insulated or shielded in an approved manner to avoid danger of burns to persons.

4-3.3.2 Interior.

4-3.3.2.1 Where a metal chimney extends through any story of a building above that in which the appliances connected to the ch imney are installed, it shall be enclosed in such upper stories, within a continuous enclosure constructed of noncombustible materials (see Section 1-3.2). T h [ enclosure shall comply with the following:

(a) The enclosure shall extend from the ceiling of the appliance room to or through the roof so as to maintain the integrity of the fire separations required by the applicable building code provisions.

(b) The enclosure walls shall have a fire resistance rating of not less than 1 hour if the building is less than 4 stories in height.

(c) The enclosure walls shall have a fire resistance rating of not less than 2 hours if the building is 4 stories or more in height.

. (d) The enclosing walls shall provide a space on all sides of the chimney to permit inspection and repair, but in no case shall it be less than 12 inches (305 mm).


(e) The enclosing wails shall be without openings.

Exception: Doorways equipped with approved self-closing ll/~2-hour fire doors may be installed at various floor levels Jor inspection purposes.

4-3.3.2.2 Where a metal chimney serving a medium heat appliance as defined in Appendix A passes through a roof constructed of combustible material, it shall be guarded by a ventilating thimble of galvanized iron or approved corrosion resistant metal, extending not less than 9 inches (229 mm) below and 9 inches (229 ram) above the roof construction, and of a size to provide not less than 18-inches (457 ram) clearance on all sides of the chimney.

4-3.3.2.3 Where a metal chimney serving medium heat appliances as defined in Appendix A is located in the same story of a building as that in which the appliances connected are located, it shall have a clearance of not less than 36 inches (914 mria) from a wall of wood frame construction and from any c6mbustible material.

4-3.3.2.4 Interior metal chimneys over 18 inches (457 ram) in diameter shall have a clearance of not less than 4 inches (102 ram) from a building wall of other than wood frame construction.

4-3.3.2.5 Interior metal chimneys 18 inches (457 mm) or less in diameter shall have a clearance of not less than 2 inches (51 ram) f rom a building wall of other than wood frame construction.

4-4 Metal Chimneys for High Heat Appliances. \

4-4.1 Construction. Metal chimneys for high heat appliances as defined in Appendix A shall be lifted with high-duty fire brick (ASTM C64, Type A) or the equivalent, not less than 41/~ inches (114 ram) thick laid on the 41/~-inch ( l l4 -mm) bed in refractory mortar (ASTM C105, high duty) or the equivalent.

4-4.1.1 The lining shall start 2 feet (.61 m) or more below the lowest chimney connector entrance and shall extend to a height of at least 25 feet (7.6 m) above the highest chimney connector entrance. Chimneys terminating 25 feet (7.6 m) or less above a chimney connector entrance shall be lined to the top.

4-4.2 Te rmina t ion (height). Metal chimneys for high heat appliances shall extend not less than 20 feet (6.1 m) higher than any portion of any building within 50 feet (15.3 m).

4-4.3 Clearance from Combustible Materia l . Metal chimneys for high heat appliances shall have sufficient clearance from buildings and structures to avoid heating combustible material

¢

211-20 CHIMNEYS} FIREPLACES~ AND VENTS

to a temperature in excess of 180°F (82.2°C) and to permit inspection, and maintenance operations on the chimney. They shall be located or shielded to avoid danger ot burns to persons.

4-5 Metal Chimneys for Incinerators.

4-5.1 Residential- type Incinerators. Galvanized steel pipe not less than No. 20 galvanized-sheet gage number or other equivalent noncombustible, fire- and corrosion-resistant material may be used for residential-type incinerators installed in locations such as open sheds, breezeways, or carports. The pipe shall comply with the following requirements.

4-5.1.1 The pipe shall be exposed and readily examinable for its full length.

4-5.1.2 Clearance not less than 18 inches (457 mm) shall be maintained from combustible material.

4-5.1.3 The pipe shall extend at least 3 feet (.92 m) above the highest point where it passes by or through a roof and at least 2 feet (.61 m) higher than any portion of a building within 10 feet (3..1 m).,

4-5.1.4 If the pipe passes through a roof constructed of combustible material, it shall be guarded by a ventilating thimble of galvanized steel or. approved corrosion resistant, noncombustible material extending not less than 9 inches (229 mm) below and 9 inches (229 mm) above the roof construction, and of a size to provide not less than 6-inch (152-mm) clearance on all sides of the pipe.

Excepdon: In lieu of the above requirement, the combustible material in the roof construction shall be cut away so as to provide not less than 18.inch (457-mm) clearance on all sides of the pipe, with any material used" to close up such opening entirely noncombustible.

4-5.2 (~ommercial and Industrial-type Incinerators.

4-5.2.1 Construction.

4-5.2.1.1 Metal chimneys for commercial a n d industrial- type incinerators shall be lined with medium-duty fire brick (ASTM C64, Type F, or the equivalent), not less than 41/'~ inches (114 ram) thick laid on the 41~-inch (114-mm) bed in refractory mor ta r (ASTM C105, medium duty), or the equivalent.

4-5.2.1.2 The lining shall start at the base of the chimney and extend continuously to the top.

4-5.2.2 Terminat ion (height).


4-5.2.2.1 Metal chimneys for commercial and industrial incinerators shall extend not less than 10 feet (3.1 m) higher than any portion of any building withifi 25 feet (7.6 m).

4-5.2.2.2 The terminus of the chimney flue for the incinerator shall be equipped with an approved spark arrester if the incinerator does not include effective means for arresting sparks and fly ash (see NFPA 82-1972):

4-5.2.3 Clearance." Metal chimneys for commercial and industrial incinerators shall be installed to provide clearances as specified in 4-3.3 for metal chimneys for medium heat appliances.

~O

211-22 CHIMNEYS, FIREPLACES, ANDVENTS

Chapter 5 Chimney Connectors and Vent Connectors

5-1 Connectors Requi red . Connectors shall be used to connect appliances to the vertical chimney or vent unless the chimney or vent is attached direcdy to the appliance.

5-2 Materials.

5-2:1 Connectors shall be made of noncombustible corrosion resistant material capable of withstanding the flue gas. temperatures produced by the appliances and of sufficient thickness to withstand physical damage.

5-2.2 Connectors for residential-type appliances shall conform to the following requirements.

5-2.2.1 Appliances Installed in Attics.

5-2.2.1.1 Connectors for listed gas appliances having draft hoods and for appliances listed for use with Type B gas vents shall be of Type B or Type L vent material.

5-2.2.1.2 Connectors for oil appliances shall be of Type L vent or factory-built chimney material.

5-2.2.1.3 Appliances other than those covered in 5-2.2.1.1 and 5-2.2.1.2 shall have the chimney directly connected to the appliance. Connectors shall not be allowed.

Exception: Listed factory-built chimney material may be used to connect an appliance to the chimney.

5-2.2.2 Appliances Not Installed in Attics.

5-2.2.2.1 Connectors for listed gas appliances and appliances equipped with a listed gas burner and draft hood shall be of Type B or Type L vent material or metal pipe having resistance to corrosion and heat not less than that ' of No. 28 gage galvanized steel.

5-2.2.3 Connectors for oil appliances, solid fuel burning appliances, domestic-type incinerators and gas appliances other than those in 5-2.2.1 and 5-2.2.2 shall be of factory-built chimney material, Type L vent material or steel pipe having resistance to corrosion and heat not le§s than that of galvanized pipe specified in Table 5-2.2.3.

5-2.3 Connectors for low heat appliance~ shall be of listed factory-built chimney material or-of steel pipe having resistance to corrosion and heat not less than that of galvanized pipe specified in Table 5-2.2.3.

CHIMNEY CONNECTORS AND VENT CONNECTORS 211-23

Table 5-2.2.3 Metal Thickness for Galvanized Steel Pipe Connectors

Diameter of Galvanized Sheet Steel Connector, inches/mm Gage No.

less than 6/152 26 6/152 to less than 10/254 24

10/254 to 12/305 22 14/356 to 16/406 20

16/406 , 16

5-2.4 Connectors for medium heat appliances and commercial and industrial incinerators shall be constructed of listed medium heat chimney sections or of steel not lighter than that designated for metal chimneys in Table 4,-1.2, and shall conform to the following requirements.

5-2.4.1 Connector sections df listed medium heat-chimneys shall be joined together using continuous welds, flanges, or couplings.

,5-2.4.2 Steel connectors shall be lined with medium-du.ty fire brick (ASTM C64, Type F) laid in fire-clay mortar (ASTM C105, medium duty), or the equivalent.

5-2.4.2.1 The lining shall be at least 2a~ inches (64 ram) thick for connectors having an inside diameter or greatest inside- cross-section dimension of 18 inches (457 ram) or less.

5-2.4.2.2 The lining shall be at least 41~ inches (114 mrr/) thick laid on the 41~-inch ( l l 4 -mm) bed for connectors having an inside diameter or greatest inside cross-section dimension greater than 18 inches (457 ram).

5-2.5 Metal connectors for high heat appliances shall conform to the following requirements.

5-2.5.1 Metal connectors for high heat appliances shall be made of steel not lighter than that designated for chimneys in Table 4-1.2.

5-2.5.2 The connectors shall be lined with high-duty fire brick (ASTM C64, Type A) or the equivalent having a thickness of not less than 4 ~ inches (114 mm) laid on the 4 x~-inch ( l l 4 -mm) bed in fire-clay mortar (ASTM C105, high duty), ,or the equivalent.

5-2.6 Masonry connectors or breeching shall be made of refractory material equivalent in resistance to heat and corrosion to high-duty fire brick (ASTM C64, Type A) not less than 41~ inches (114 mm) thick.

O

211~24 CHIMNEYS~ FIREPLACES~ AND V E N T S

5-3 Leng th . A connector shall be as short and straight as possible. The appliance shall be located as close a s oractieable to thCchiri ir iey O r Vent_ " " - . . . . . . : . . . . :

5-3.1_ The horizontal rtin /)f an uninsula ted connector to a na tura l draft chimney, or vent, ' serving a single appl iance shall be not more than 75 percent of the height of the vertical portion of the chimney or vent above the connector.

Exception: When part of an engineered venting system.

5-3.2 The horizonthl run of an insulated connector to .a na tu ra l draft chimney, or vent, serving a single gas or l iquid fuel fired appliance shall be not more than .100 percent of the height of the vertical port ion of the chimney or vent above the connector.

Exception: When part of an engineered venting system.

5-3.3 The horizontal length, design, and construction of combined connectors, or connectors to a manifold jo in ing two or more appliances to a chimney or vent, shall be de termined in accordance with approved engineering methods.

5-4 Size.

5-4.1 The connector, for its entire length, shall be sized in accordance with apwoved engineering methods.

5-4.2 As an al ternate to 5-4.1, the following requirements may be applied.

5-4.2.1 The effective area of a connector for a s~gle ap- plianc e shall be not less than the area of the appliance flue collar.

.5-4.2.2 A connector or manifold serving two or more appliances shall have an effective area equivalent 'to the combined ~ areas of the app l i ance flue collars or individual cc;nnectors.

5-4:2.3 Linings, if used, shall not reduce the required effective area of the connector.

5-5 C l e a r a n c e .

5-5.1 Clearances from connectors to combust ible mater ia l . shall be in accordance with the following requiremefits for both unprotected and protected installations.. " "

5-5.1.1 Clearances from connectors to unprotected combustible mater ial shall be ,in accbrdance with Tab le 5-5(a) arid Figure 5-5.

C H I M N E Y C O N N E C T O R S AND V E N T C O N N E C T O R S ' 211-25

Table 5-5 (a) Chimney Connector and Vent Connector Clearances from Combustible Materials

Description of Appliance

Minimum Clearance,

inches (mm) (See Note 1)

RESIDENTIAL-TYPE APPLIANCES Column 1, Appendix A

Single-Wall Metal Pipe Connectors Gas Appliances Without Draft Hoods 18 (457) Electric, Gas, andOil Incinerators 18 (457) Oil and Solid-Fuel Appliances 18 (457) Unlisted Gas Appliances With Draft Hoods- 9 (229) Boilers and Furnaces Equipped With Listed Gas Burners and

With Draft Hoods 9 (229) Oil "Appliances Listed as Suitable For Use With Type L

Vents .." 9 (229) Listed Gas Appliances With Draft Hoods. See Note 3. 6 (152)

Type L Vent Piping Connectors Gas Appliances Without Draft Hoods 9 (229) Electric, Gas, and Oil Incinerators - 9 (229) Oil and Solid-Fuel Appliances 9 (229) Un!istedGas Appliances With Draft Hoods 6 (152) t~ouers ana furnaces Equipped With Listed Gas Burners ' and With Draft Hoods "6 (152-) Oil Appliances Listed As Suitable For Use With Typic L Vents (See Note 2) Listed Gas Appliances With Draft Hoods (See Note 3) Column 1, Appendix B

Type B Gas Vent Piping Connectors Listed Gas Appliances-With Draft Hoods (See Note -3)

L O W HEAT APPLIANCES Columns'2 & & .Appendix A

Single-WaU Metal P ipe Connectors Gas, Oil, and Solid-Fuel Boilers, Furnaces, and Water Heaters 18 (457) Ranges, Restaurafit Type 18 (457) Oil Unit Heaters 18 (457) Unlisted Gas Unit Heaters 18 (457) Listed Gas Unit Heaters With Draft Hoods 6 (152) Other Low-Heat Industrial Appliances 18 (457)

MEDIUM HEAT APPLIANCES Column 4, Appendix A

Single-WaU Metal Pipe Connectors • All Gas, Oil, and Solid-Fuel ~ppliances 36 (914)

HIGH HEAT APPLIANCES Column 5, Appendix A"

or Metal Connectors " ~ Masonr~r . I , AI! Gas, Oil, and Solid-Fuel Appliances (See Note 4)

(.Notes to Table 5-5(a) on following page.)

211-26 CHIMNEYS~ FIREPLACES, AND'VENTS

Notes to Table 5-5(a)

• Note 1: These clearances apply except if the listing of an appliance specifies dif- ferent clearance, in which case the listed clearance takes precedence.

Note 2: i f listed Type L vent piping is used, the clearance may be in accordance with the vent listing.

Note 3: If listed Type B or Type L vent piping is used, the clearance may be in accordance with the vent listing.

Note 4: Clearances shall be based on good engineering practice and acceptable to the authority having jurisdiction'.

The clearances from connectors to combustible materials may be reduced if the combustible material is protected in accordance with Table 5-5(b).

C O N S T R U C T I O N USING C O M B U S T I B L E M A T E R I A L ) P L A S T E R E D OR U N P L A S T E R E D •

Y N N N N N N

. . c , , / ~ , . , - \ c

Figure 5-5

A equals the required clearance with no protection specified in Table 5-5(a).

B equals the reduced clearance permitted in accordance with Table 5-5(b).

The protection applied to the construction usingcombustible material shall extend far enough in each direction to make C equal t eA .

5-5.1.2 Clearances from connectors to combustible material may be reduced if the combustible material is protected by an engineered protection system acceptable to the author i ty having jurisdict ion, or by the use of materials or products listed for protection purposes, or in accordance with Tab le 5-5(b) and Figure 5-5.

5-5.2 Engineered systems installed for protection of combustible materials shall reduce the tempera ture of such materials to not over 180°F (82°C). System design shall be based upon applicable heat transfer principles taking into account the geometry of the system, the heat loss characteristics of the structure behind the combust ible material , and possible abnorma l operat ing conditions of heat producing sources.

CHIMNEY CONNECTORS AND VENT CONNECTORS 211-27

Table 5-5 (b) Connector Clearances, Inches, With Specified Forms of Protection l, ~, ~

Type of Protection

Applied to the combustible material and covering all surfaces within the distance specified as the required clearance with no protection• (See Fig. 5-5. ) Thicknesses are minimum.

Where the required clearance with no protection is:

36 inches 18 inches 9 inches 6 inches (914 ram) (457 ram) (229 mm) (152 mm)-

(in./mm) (in./mm)-(in./mm) (in./mm)

(a) ~ in. asbestos millboard spaced out 1 in . . . . . . . . . . . 30/762 12/305 6/152 3/76

(b) 0.013u/0.330 mm (28 gage) sheet metal on 1/~ in. asbestos millboard . . . . . . . . . 24/610 12/305 4/102 2/51

(c) 0.013"/0.330 mm (28 gage) sheet metal spaced out 1 i n . . 18/457 9/229 4/102 2/51

(d) 0.013~/0.330 mm- (28 gage) sheet metal on ~ in. asbestos millboard spaced out 1 in. . . 18/457 9/229 4/102 2/51"

(e) ~ in. asbestos millboard on 1 in. mineral wool bats reinforced with wire mesh or equivalent . 18/457 6/152 4/102 2/51

(f) 0.027~/0.686 mm (22 gage) sheet metal on 1 in. mineral wool bats reinforced with wire or equivalent . . . . . . . . 12/305 3/76 • 2/51 2/51

Notes to Table 5-5(b)

1. Spacers shall be of noncombustible material. 2. Methods (a) (b) (c) and (d) require ventilation between sheet, material and

protected combustible material. If ventilat on may be mpa red use method (e) or (f). 3. Mineral wool bats (blanket or board) shall have a minimum density of 8 lb per

ft = (0.128 g/cc) and a minimum melting point of 1500°F (816°C).

5-5.3 All clearances shall be measured f rom the outer surface of the connector to the combust ible material, disregarding any in tervening protection applied to the combustible material bu t in no case shall the clearance be such as to interfere with the require- men t for accessibility.

5-5.4 Materials and products listed for the purpose of reducing clearance to combustibles shall be installed in accordance with the

• condit ions of t h e listing and the manufac turer ' s instructions.

5-6 Locat ion. W h e n the connector used for a gas appl iance having a draft hood must be located in or pass through a crawl space or other cold area, that port ion of the connector shall be of listed Type B or Type L vent mater ial or be provided with equivalent means of insulation.

211-28 CHIMNEYS~ F I R E P L A C E S ~ A N D V E N T S

5-7 Installation.

5-7.i A connector to a masonry chimney - '--" ..... -J.~u . . . . . u ~|L~LII t i l t ~JUSLL U A L U I I U

the wall to the inner face or liner but not beyond, and shall be firmly cemented to masonry.

Exception: A thimble may be "used to .facilitate removal o-f the chimney connector .for cleaning, in which case the thimble shall be permanently cemented in place with high-temperature cement.

5-7.2 A chimney connector or vent connector shall not pass through any floor or ceiling; nor through a fire wall or fire partition.

5-7.3 Connectors for listed gas appliances with draft hoods (Appendix B, Column I) and oil appliances listed for Type L vents (Appendix B, Column I I I ) may pass through walls or partitions constructed of combustible material if:

(a) Made of listed Type B or Type L vent material for gas appliances, listed Type L vent material for oil appliances, and installed with not less than listed clearances to combustible material, or

(b) Made of single-wall metal .pipe an'd guarded by a ventilated metal thimble not less than 4 inches (102 mm) larger in diameter than the vent connector.

5-7.4 Connectors for residential-type appliances (Appendix A, Columr~. I) may pass .through walls or partitions constructed of combustible material if made of listed factory-built chimney material and installed in accordance with the conditions of the listing and the manufacturer's instructions.

5-7.5 Connectors for residential-type and low heat appliances (Appendix A, Columns I, I I and I I I ) may pass through walls or partitions constructed of combustible material if they are guarded at the point of passage by :

(a) Metal ventilated thimbles not less than 12 inches (305 ram) larger in diameter than the connector; or by

(b) Metal or burned fire clay thimbles built in brickwork or other approved fireproofing materials extending not less than 8 inches (203 ram) beyond all sides of the thimble.

5-7.6 ' I n lieu of thimbles all com.bustible ,material in the wall or 'partition shall be cut away f rom the connector a sufficient distance to provide the clearance required from such connector. Any material used to close up such openings shall be noncombustible insulating material.

C H I M N E Y C O N N E C T O R S A N D V E N T C O N N E C T O R S 211-29

• 5-7.7 A connector for a medium or high heat appliance (Ap- pendix A, Columns IV and V) shall not pass through walls or partitions constructed . . . . . . . . . . . . . . OI c o I n l J u S U U l t ; l l l i t tull i~.t•

5-7.11 Connectors shall maintain a pitch or rise of at least inch (6.4 mm) to the foot (horizontal length of pipe) from the'

appliance to the chimney.

5-7.9 Connectors shall be installed so as to avoid sharp turns or other construction features which would create excessive resistance to the flow of flue gases.

5-7.10 A device.which will obstruct the free flow of fl0e gases shall not be installed in a connector, chimney or vent.

Exception: This requirgment shall not be construed to prohibit the use of devices specifically listed for installation in a connector, such as heat re- claimers, draft regulators, and safety controls.

5-7.11 Connectors shall be securely supported and joints fastened with-sheet-metal Screws, rivets, or other approved means.

5-7.12 The entire length of a connector shall be readily accessible for inspection, cleaning, and replacement.

Exception: When listed materials are used and previous approval has been obtained from the authority having jurisdiction.

5-7.13 A vent connector shall not be connected to a chimney flue serving a fireplace.

Exception: When the fireplace opening is sealed or the chimney flue which vents the fireplace is permanently sealed below the connection.

5-8 Interconnect ion.

5-8.1 Connectors serving,appliances operating under natural draft shall not be connected into any portion'of a mechanical draft system operating under positive pressure•

5-8.2 Two or more fuel-burning appliances may be connected • to a single chimney or vent provided:

(a) Sufficient draft is available fo r safe combustion in each appliance, and ._

(b) Sufficientdraft is available for removal of all the products of combustion safely-to the outdoors, and

( (c) Gas and oil appliances so connected shall be equipped

with primary safety controls•


5 - 9 Dampers.

5-9.1 Manually operated dampers shall not be placed in chimneys, vents or connectors of stoker fired, liquid or gas-burning appliances. Fixed baffles on the appliance side of draft hoods and draft regulators shall not be classified as dampers.

5-9.2 Automatically operated dampers shall be of listed type designed to maintain a safe dhmper position at all times and arranged to prevent the initiation or increase of firing until the damper is opened to a safe position.

5-10 Draf t Hoods. For information concerning the use and installation of draft hoods, refer to the National Fuel Gas Code, NFPA 54-1974.

5-11 Draft Regulators?

5-11.1 Gas appliances connected to chimneys, other than those required to be installed with draft hoods by the National Fuel Gas Code, NFPA 54-1974, may be installed with draft regulators if in accordance with the appliance manufacturer 's instructions.

5-11.2 Solid fuel-burning appliances may be installed with draft regulators to reduce draft intensity. Such regulators shall be installed and set in accordance with the instructions furnished with the appliance or the draft regulator.

5-11.3 A barometric draft regulator, if used, shall be instal led in the same room or enclosure as the appliance in such a manner that no difference in pressure between "the air in the vicinity of the regulator and the combustion air supply will be permitted.

tFor information concerning the use and installation of draft regulators with oil-burning al~pfiances , refer to the Standard for the Installation of Oil Burning Equipment, NFPA 31-1974.

VENTS" 2 1 1 - 3 1

Chapter 6 Vents

6-1 Types and Uses. (See Appendix B.)

6-1.1 Type B gas vents shall b e used to vent only listed gas appliances with draft hoods and other gas appliances listed for use with Type B gas vents.

Exception: Type B gas vents shall not be used for venting:

(a) Vented wall furnaces listed for use with Type B W gas vents only. (b) Incinerators.

(ci Appliances which may be converted readily to the use of solid or liquid fuels.

(d) Combination gas-oil burning appliances.

(e) Appliances listed for use with chimneys only.

6-1.2 Type BW vents shall be used only with listed vented gas wall furnaces having a capacity not greater than that of the listed Type BW gas vent.

:~1.3 Type L vents'shall b eu sed only with appliances listed as suitable for such use and gas appliances listed as suitable for use with Type B gas vents.

6-1.4 .Single-wall metal pipe used to vent gas appliances shall conform to the following requirements.

6-1.4.1 Single-wall metal pipe shall not be used to vent incinerators.

Exception: For residential incinerators as provided in g-5. 1.

6,1.4.2 The pipe shall be of sheet copper not lighter than No. 24 B ~ & S gage or of galvanized iron not lighter than No. 20 galvanized sheet gage number.

: .6-1.4.3 Single-wall metal pipe shall be used only for runs directly from the space in which the appliance is located through "the roof or exterior wall to the outer air.

6-1.4.4 Single-wall metal pipe shall not originate in any unoccupied at t ic or concealed space and shall not pass through any attiC, inside wall, concealed space nor through any floor or ceiling.

6-2 Location. Outside vents for appliances used in cold climates shall be insulated.


.6-3 Termination.

6-3.1 All vents shall t e rmina te above the roof surface. (See Appendix D.).

Exception: As provided in 6-3.5 and 6-6.

6-3.1.1 Vents installed with mechanical exhausters-shal l terminate not less than 12 inches (305 m m ) above the highest point where they pass through the roof surface.

6-3.1.2 Vents installed with listed caps shall terminate in accordance with the terms of the cap's listing.

6-3.1.3 Vents installed without listed caps or mechanical exhausters shall extend 2 feet (.61 m) above the highest point where they pass through the roof surface of a building and at least 2 feet (.61 m) higher than any portion of a building within 10 feet (3.1 m).

/

6-3.2 N a t u r a l draft vents for gas appliances shall terminate at an elevation not less than 5 feet (1.53 m) above the highest connected appliance outlet•

,~^cepa .... As provided in 6- 3. 3 and 6- 6.2.

6-3.3 Natural draft gas vents serving yen.ted wall furnaces shall terminate at an elevation not less than 12 feet (3.7 m) above the bot tom of the furnace.

6-3.4 Vents passing through roofs shall extend through roof flashing.

6-3.5 Mechanical draft systems need not comply with 6-3.1 and 6-3.3 provided they comply with the foilowing:

- (a) The exit terminal of the mechanical draft system shall b e located not less than 12 inches (305 ram) from any opening through

• which combustion products could enter the building nor less than 2 feet (.61 m) from an adjacent building, and not less than 7 feet (2.1 m) above grade when located adjacent to public walkways.

(b) The exit terminal shall be so arranged that flue gases are not directed so as to jeopardize people, overheat combustible structures or enter b.u!ldings.- . ".

(c) Forced draft systems and all portions of induced draft systems under positive pressure during operation shall be designed and installed so as to be gastight or so a s to prevent leakage of combustion products into a building.

VENTS 211--33

6-4 M a r k i n g of Gas Vents. In those sections of the country where solid and liquid fuels are used extensively, gas vents shall be plainly and permanently identified by a label reading:

"This gas vent is for appliances which burn gas only. Do not coflnect to incinerators or solid- or liquid-fuel burning appliances."

6-5 Installation?

6-5.1 Type B, Type BW, and Type L vents shall be installed in full compliance with the terms of their listing.

6-5.2 Vents which pass through floors of buildings requiring the protection of vertical openings shall be enclosed within an approved enclosure.

• 6-5.2.1 The enclosure walls shall have a fire resistance ra'ting of not less than 1 hour when such vent is located in a building less than 4 stories in height.

6-5.2.2 The enclosure walls shall have a fire resistance rating of not less than 2 hours when such vent is located in a building 4 stories or more in height.

6-5.3, Single-wail metal pipe shall be installed as follows:

6-5.3.1 Single-wall metal pipe shall be installed with minimum clearances from combustible material as follows:

(a) Gas appliances without draft hoods, 18 inches (457 ram).

(b) Unlisted gas appliances equipped with draft hoods, 9 inches (229 ram).

(c) Boilers and furnaces equipped with listed conversion gas burners and with draft hoods, 9 inches (229 mm).

(d) Listed gas appliances with draft hoods, 6 inches (152 mm).

Exception: Residential incinerators.,

6-5.3.2 Where a single-wall metal pipe passes through an exterior wall cofistructed of combustible material, it shall be guarded at the point of passage by a ventilating metal thimble not smaller than the following: •

Exception:In lieu of ihimble protection, all combustible material in the wall shall be cut awayJrom the pipe a suffcient distance to provide the clearance

• 'Additional re uirements foi" the installation of venting systems serving gas q appliances appear in the National "Fuel Gas Code, NFPA 54-1974.

t ~

t ~


required by 6-5.3. 1 .from such pipe to combustible material, with any material used to close up such opening entirely noncombustible.

(a) For listed gas burning appliances with draft hoods 4 inches (102 ram) larger in diameter than the pipe.

Exception No. I: Residential incinerators.

Exception No. 2: When there is a run of not less than 6feet ( 1.8 m) oJ pipe in the open, between the draft hood outlet and the thimble, the thimble may be 2 inches (51 mm) larger in diameter than the pipe.

(b) For unlisted gas burning appliances with draft hoods 6 inches (152 mm) larger in diameter than the pipe.

(c) For ' gas appliances without draft hoods 12 inches (305 mm) larger in diameter than the pipe.

6-5.3.3 Where a single-wall metal .pipe passes through a roof constructed of combustible material it shall be guarded at the point of passage as follows:

(a) As specified for passage through a combustible exterior wall by 6-5.3.2, or

(b) With listed gas appliances that can be connectdd to Type B gas vents, by a noncombustible, nonventilating thimble not less than 4 inches (102 mm) larger in diameter than the vent pipe and extending not less than 18 inches (457 mm) above and 6 inches (152 mm) below the roof with the annular space open at the bottom and closed only at the top.

6-6 Special Venting Arrangements. '

6-6.1 Direct Vent Appliances (Sealed combustion system appliances). Direct vent appliances (sealed combustion system appliances) shall be listed and shall be installed in accordance with their listing and the manufacturer 's instructions.

6-6.2 Ventilatifig Hoods and Exhaust Systems.

6-6.2.1 When ventilating hoods and exhaust systems serving commercial cooking appliances are used to vent gas-burning appliances installed in commercial applications, the connector from the appliance shall terminate under the hood not less than 18 inches (457 ram) from any grease filter or 'screen installed in the hood?

~For information on ventilation of restaurant cooking equipment see the Standard for the Installation of Equipment for the Removal "of Smoke and Grease-Laden Vapors .from Commercial Cooking Equipment, NFPA 96-1976.

t

VENTS 2 1 1 - 3 5

6-6.2.2 When automatically operated appliances, such as water heaters, are vented through natural draft ventilating hoods, dampers shall not be installed in the ventilating system.

6-6.2.3 When automatically operated appliances, such as water heaters, are vented through a ventilating hood or exhaust system equipped with a mechanical exhaust system, the appliance control system shall be interlocked so as to permit appliance operation only when the mechanical exhaust system is in operation [see 6-3.5(c)1.

6-6.2.4 A ventilating hood shall be installed above, an open-top broiler in a residence.

6-6.2.4.1 The hood shall be made with tight joints of sheet copper not lighter than No. 24 B & S gage or galvanized sheet steel not lighter than No. 28 galvanized sheet gage.

6-6.2.4.2 A clearance of not less than 1~ inch (6.4 ram) between the hood and the underside of combustible material or metal cabinets shall be provided.

6-6.2.4.3 The vertical clearance'above the broiler to the underside of combustible material or metal cabinet protected by the hood shall be not less than 24 inches (610 mm).

6-6.2.4.4 The width and breadth of the hood shall be not less than that of the open-top broiler unit.

6-6.2.4.5 The hood shall be centered over the unit.

6-6.2.4.6 The hood shall be exhausted directly through an outside wall to the outside or connected to a suitable chimney flue used for no other purpose. The connecting duct shall conform to the following:

(a) Connecting ducts shall be made of galvanized sheet metal not lighter than No. 28 gage.

(b) A clearance of not less than 6 inches (152 mm) shall be provided between the exhaust duct and unprotected combustible material.

Exception: This clearance may be reduced iJ the combustible material is protected in accordance with Table 5-5(b).

6-6.3 Clothes Dryers.

6-6.3.1 All ducts .expelling lint shall be provided with a lint collector.

Exception: When the dryer is so equipped.


6-6,3.2 For Type 1 gas-fired clothes dryer exhaust see the " Nationai Fuel Ga~ . . . . . . . . A ~ ta-TA j " r - - x / t ~ r .

6-6.3.3 Type 2 clothes dryers shall be exhausted to the outside air.

6-6.3.4 Provision for make-up air shall be provided for Type 2 clothes dryers, with a minimum free area of 1 square inch (645.2 m m ~) for each 1000 Btu per hour (1055kJ/hr) total input rating of the dryer(s) installed.

&6.3.5 'A clothes dryer exhaust shall not" be connected into any chimney connector, vent connector, chimney or vent.

6-6.3.6 Ducts for exhausting clothes dryers shall not be put together with sheet-metal screws or other fastening means which extend into the duct and which would catch lint and reduce the efficiency of the exhaust.

6-6.3.7 Exhaust ducts for Type 2 clothes dryers shall be constructed of sheet metal or other noncombustible material. Such ducts shall be of adequate strength to meet the conditions of service with minimum thicknesses equivalent to No. 24 galvanized sheet gage.

6-6.3.8 Exhaust ducts for Type 2 clothes dryers shall have a clearance 'of at least 6 inches (152 mm) to combustible material.

Exception: Exhaust ducts for Type 2 clothes dryers may be installed with reduced clearances to combustible material provided the combustible material is protected as described in Table 5-5(b) .

6-6.3.9 When ducts pass through walls, floors, or partitions, the ~pace around the duct shall be sealed with noncombustible material.

6-6.3.10 Multiple installations of Type 1 and Type 2 clothes dryers shall be made in a manner to prevent adverse operation due to back pressures that might be created in the exhaust. Common exhaust vents which pass through floors of buildings requiring the protection of vertical openings shall be enclosed witt{ approved walls having a fire resistance rating of not less than 1 hour when such chimneys are located in a building less than 4 stories in height, and not less than 2 hours when such chimneys are located in a building 4 stories or more in height.

FIREPLACES 2 1 1 - 3 7

7-1 Factory-built Fireplaces. Factory-built fireplaces shall be listed and shall be installed in accordance with the conditions of the listing. Hear th extensions shall be provided in accordance with the manufacturer 's instructions.

7-2 Factory-built Fireplace Stoves. Factory-built fireplace stoves shall be listed and shall be installed .in accordance with the conditions of the listing. Hearth extensions shall be provided in accordance with the manufacturer 's instructions.

7-3 Factory-bui l t Solid Fuel Room Heaters. Factory-buih solid fuel room heaters shall be listed and shall be installed in accordance with the conditions of the listing. Protection for c o m - bustible floors and walls shall be provided in accordance with the manufacturer 's instructions.

7-4 Masonry Fireplaces.

7-4.1 Fireplaces shall be constructed Of solid masonry or of reinforced portland or refractory cement concrete with back and sides of the thickness specified in 7-4.1.1 or ~/-4.1.2.

Exception: As provided in 7- 7.

7-4.1.1 Where a lining of low-duty firebrick (ASTM C64, Type G), or the equivalent, at least 2 inches (51 mm) thick laid in fire-clay mortar (ASTM C105, medium duty), or the equivalent, or other approved lining is provided, the total thickness of back and sides, including the lining, shall be not less than 8 inches (203 mm).

7-4.1.2 Where the lining described in 7-4.1.1 is not provided, t h e thickness of back and sides shall be not less than 12 inches (305 mm).

7-4.2 Steel fireplace units incorporating a firebox liner of not ' less than 1/~-inch (6.4-ram) thick steel and an air chamber shall be installed .with masonry to provide-a total thickness at the back and sides o£ not less than 8 inches (203 ram), not less than 4 inches (102 ram) of which shall be solid masonry.

7-4.3 Warm air ducts employed with steel fireplace units of the circulating air type shall be constructed of metal or masonry.

7-4.4 Fireplace hearth extensions shall be provided of approved noncombustible material for all fireplaces.

211-38 C H I M N E Y S , F I R E P L A C E S , A N D V E N T S

t

7-4.4.1 Where the fireplace opening is less than 6 sq. ft. (.56 mS), the hear th extension shall extend at least 16 inches (406 mm) in front of, and at least 8 inches (203 ram) beyond each side of the fireplace opening.

7-4.4.2 Where the fireplace opening is 6 sq. ft. (.56 m 2) or larger, the hearth extension shall extend at least 20 inches (508 mm) in front of, and at least 12 inches (305 ram) beyond each side of the fireplace opening.

7-4.4.3 Where a fireplace is elevated above or overhangs a floor, the hearth extension shall also extend over the area under the fireplace.

7-4.4.4 Fireplaces constructed of masonry or reinforced portland or refractory cement concrete shall have hearth extensions of brick, concrete, stone, tile or other approved noncombustible material properly supported and with no combustible material against the underside thereof. Wooden forms or centers used during the construction of hearth and hearth extension shall be removed when the construction is completed.

7-4.5 All wood beams, joists and studs shall be tr immed away from fireplaces. "Headers supporting tr immer arches at fireplaces shall be not less than 20 inches (508 mm) from the face of the chimney breast. Tr immers shall be not less th~in 6 inches (152 m m ) from the inside face of the nearest flue lining.

7-4.6 Woodwork shall not be placed within 4 inches (102 mm) of the back face of a fireplace.

Exception: This requ#ement shall not prevent plastering directly on the masonry or on metal lath and metal.Jurring.

7-4.7 Woodwork shall not be placed within 6 inches (152 mm) of a fireplace opening. Woodwork above and projecting more than 1 ~ inches (38 mm) from a fireplace opening shall not be placed less than 12 inches (305 mm) from the top of a fireplace opening.

Appendices A, B, C, D, and E follow on pages 40-49.

t ~ ",4

• A p p e n d i i x A

This Appendix is not a part of thia N F P A ~tandard but is included/or i~forrnational purposes only.

Chimney. Selection Chart

Chimneys for Residential Type

Appliances

Chimneys for LOW HEAT Appliances Chimneys for MEDIUM HEAT

Appliances t

Chimneys for HIGH HEAT Appliances 3

Building Heating Industrial Type Appliances Low Heat Appliances

1. FaetoW built. 1. Factory built. 1. Factory built (industrial 1. Factory built (industrial 1. Masonry (high heat typse).* 2. Masonry (residential type). 4 2. Masonry (low heat type). 4 low heat type)• medium heat type). 2. Metal (highheattype~.

Masonry (low heat type)•* 2. Masonry (medium heat 3. Metal (low heat type), a 2~ Metal (low heat type). 6 type). 4 3. Metal (medium heat type). 5

TYPES OF APPLIANCES TO" BE USED WITH EACH TYPE CHIMNEY

Column II A. All appliances shown in

Column I. B. Nonresidential type build-

ing heating appliances for heating a total volume of space exceeding• 25,000 cubic feet (708 m3). *

C. Steam boilers operating at not ove r 1000°F (538°C) que, gas temperature; pressing ma- chine boilers.

Column III All appliances shown in Columns I and II, and appliances such as:

1. Annealing baths for hard glass (fats, paraf- fine, salts, or metals).

• 2. Bake ovens (in bakeries). 3• Boiling vats, for wood

fibre, straw, lignin, etc. ' 4• Candy furnaces.

5 • Coffee roasting ovens. 6. Core ovens. 7. Cruller furnaces. 8. Feed drying ovens. 9. Fertilizer drying ovens.

10. Fireplaces, other than residential type.

11. Forge furnaces (solid . fuel). , ,

12. Gypsum kilns. 13. Hardening furnaces (be-

low dark red). 14. Hot air engine furnaces. 15. Ladle drying furnaces. 16. Lead melting furnaces.

Column, IV All appliances - shown in Columns I, II and III, and appliances such as:

1• Alabaster gypsum kilns. 2• Annealing furnaces (glass

or metal). 3. Charcoal furnaces. 4. Cold stirring furnaces. 5. Feed driers (direct fire

heated). 6• Fertilizer driers (direct

fire heated). 7. Galvanizing furnaces. 8• Gas producers.

- 9• Hardening furnaces (cherry to pale red).

10. Incinerators, commercial and industrial type•

11. L=,hrs and glory holes. 12. Lime kilns• 13. Linseed oil boiling fur-

naces. 14. Porcelain biscuit kilns. 15. Pulp driers (direct fire

heated).

Column I • A. Residential type appliances.

such as: 1. Ranges. 2• Warm alr furnaces. 3. Water heaters. 4. Hot water heating

boilers• 5. Low pressure steam

heating boilers• 6• Incinerators• 7. Floor furnaces• 8. Wall furnaces. 9. Room heaters.

10• Fireplace stoves. B. Fireplaces.

Column V All appliances showll in Columns I, II, I l l , and IV and appliances = such (is:

1. Bessemer retorts. 2• Billet and bloom fur-

naces. 3. Blast furnaces• 4. Bone calcining furnaces• 5. Brass furnaces• 6. Carbon point furnaces. 7• Cement brick and tile

kilns• 8• Ceramic kilns• 9• Coal and water g~,s re-

torts• 10• Cupolas. I1• Earthenware kilns• 12. Glass blow furnaces. 13• Glass furnaces (smelt-

ing). 14• Glass kilns. =" 15. Open hearth furnaq;es. 16. Ore, roasting furnaces. 17. Porcelain baking and

glazing kilns•

7

C3

;>

<

Column III 17. Nickel plate (drying)

furnaces• "18. Paramne furnaces. 19. Recuperative furnaces

(spent materials). 20. Rendering furnaces. 21. Restaurant type cooking

appliances using solid or liquid fuel.

22. Rosin melting furnaces. 23. Stereotype furnaces• 24. Sulphur furnaces• 25. Tripoli kilns (clay, coke

and gypsum)• 26• Type foundry furnaces. 27. Wood drying furnaces. 28. Wood impregnating fur-

naces. 29. Zinc amalgamating fur-

naces.

Column IV 16. Steam boilers operating

a t over lO00°F (538°C) flue gas temperature.

17. Water-glass kiln. 18. Wood-distilling furnaces. 19. Wood-gas retorts.

Column V 18. Pot-arches. 19. Puddling furnaces. 20. Regenerative furnaces• 21. Reverberatory furnaces. 22• Stacks, cerburetolr or

superheating • furnaces (in water gas works).

23. Vitreous enamelin!l ovens (ferrous metals).

24. Wood carbonizing fur- , neces•

*Nonresidential type building heating appliances for heating a total volume of space not to exceed 25,000 cubic feet may be connected to chimneys for residential type appliances•

• NOTE 1 : Appliances otherwise classed as high heat appliances may be considered as medium heat appliances if not larger than 100 Cubic feet (2.83 m s ) in size.

NOTE 2: When such appliances are larger than 160 cubic feet (2.83 .m a) in size, and other furnaces classified as high heat appliances in accordance with nationally recognized good practice.

NOTE 3: Continuous operating equipment of the counter current type may not require the type of chimney indicated by general types of appliances.

NOTE 4: For construction and other provisions for masonry chimney installation see Chapter 3.

NOTE 5 : For construction and other provisions for metal chimney installation see Chapter 4.

NOTE 6: Regardless of appliance type classification, factory-built chimneys may be used at temperatures not exceeding 1000 ° F (538°C) for residential type and building heating appliance chimneys and not exceeding 1800°F (982°C) for medium heat app!ianc_e chimneys.

6/,£

A p p e n d i x B

This Appendix is not a part of this N F P A Standard but is included for informational purposes only.

V e n t S e l e c t i o n C h a r t

TYPE OF V E N T

TYPE B - GAS 2 TYPE B W - GAS ' TYPE L - OIL 1 METAL PIPE 1

Column I

All listed gas appliances with draft hoods such as:

1. Central furnaces. 2. Duct furnaces.

Column I I

1. Vented wall furnaces listed for use with Type BW vents only.

Column I I I

1. Low temperature flue gas appliances listed for use with Type L vents.

2. Gas appliances shown in

Column I V

Incinerators used outdoors, such as in open sheds, breezeways or carports as provided in 4-5.1. Gas appliances shown in Column I. Listed residential and low heat gas appliances without draft hoods and unlisted residential and low heat gas appliances with or without draft hoods.

3. Floor furnaces. 4. Heating boilers. 5. Ranges. 6. Built-in ovens. 7. Vented wall furnaces

listed for use with Type B vents.

8. Room heaters. 9. Water heaters.

10. Horizontal furnaces. 11. Uni t heaters.

Column I. 2.

3.

NOTE 1 : Installation requirements in Chapter 6.

Z

Chimney Service

Residential Type Appliances (Appendix A, Col. I) . ,

Stoves, cooking ranges, warm air furnaces, water heaters, low pressure boilers, fireplaces, appliances for heating not more than 25,000 cu, ft. (708 m ~) and other low heat appliances in dwellings only:

Solid masonry units or reinforced concrete with fire-clay flue liner extending from 8 in. (203 mrn) below connector or fireplace throat

Rubble stone masonry with similar lining Factory Built

/ A p p e n d i x C

This Appendix is not a part of this N F P A Standard but is included for informational purposes only.

T h i c k n e s s a n d T e r m i n a t i o n A b o v e R o o f s o f C h i m n e y s

Thkkness inches~ram (Minimum)

Walls Lining

4/102 5/~/16 12/305 5/~/16

as listed

Termination feet/m

(Minimum)

3/.92 above roof 2/.61 above any portion of any building within

• ' 1 0 f t . ( 3 . 1 m ) "

See Appendix D.

Low Heat Appliances (Appendix A, Cols. II & I l l )

Stoves, cooking ranges, warm air furnaces, water heaters, low pressure boilers, fireplaces, appliances for heating more than 25,000 cu. ft. (708 m 3) and other low heat appliances other than in dwellings :

Solid masonry units or reinforced concrete with fire-clay flue liner extending from 8 in. (203 mm) below connector 'or fireplace throat

Rubble stone masonry with similar lining Metal, no lining required Factory Built

81203 ~ / ! 6 } 12/305 ~ / 1 6

see 4-1 as listed

3/.92 above roof 2/.61 above any portion of any building within 10 ft. (3.1 m ) . - See Appendix D.

(continued)

7

OSf

(Appendix C continued)

Chimney Service

Medium Heat Appliances (Appendix A, Col. IV)

Solid masonry units or reinforced concrete with fire brick lining • laid in fire-clay mortar, lining extending from 2 ft. (.61 m)

below to 25 ft. (7.63 m) above connector entrance to chimney

Rubble stone masonry with similar lining

Metal with similar lining

Factory Built

"High Heat Appliances (Appendix A, Col. V)

Double Wall Masonry:

Outer .wall of solid masonry units or reinforced concrete

Air space Inner wall, total thickness 8 in. (203 mm) of solid masonry units or reinforced concrete with fire brick lining laid in refractory mortar and extending from base to top

Metal with fire brick lining laid in refractory mortar and extending from 2 ft. (.61 m) below to 25 ft. (7.63 m) above connector entrance to chimney

Thickness inches~ram

. ,(Minimum) Walls Lining

8/203 4 ~ / 1 1 4

12/305 41/~/114

see 4-1 4 ~ / 1 1 4

as listed

8 / 2 0 3

2 / 5 1 -

31/~/89 4 ~ / 1 1 4

see 4-1 4 ~ / 1 1 4

Termination feet/m

(Minimum)

!0/3.1 higher than any portion of any building within 25 ft. (7.63 m)

20/6.1 higher than any portion of any building within 50 ft. (15.25 m)

L"

U2

E L

t~

Chimney Service

Incinerators

Residential Type

Solid masonry units or reinforced concrete with fire-clay flue liner extending from 8 in. (203 ram) below connector to chimney top Rubble stor~e masonry with similar lining

Metal, for use only in open sheds, breezeways, carports

Factory Built

Chute Fed"

Solid masonry units or reinforced concrete walls

Combined hearth and grate area 7 sq. ft. (.65 m z) or less: Fire brick lining in portion extending to 10 ft. (3.1 m) above combustion chamber roof Fire-clay flue liner in portion more than 10 ft. (3.1 m) above combustion chamber roof

.Combined hearth anti grate area more than 7 sq. ft] (.65 m2): Fire brick lining in portion extending to 40 ft. (12.2 m) above combustion chamber roof Fire-clay flue liner in portion more than 40 ft. (12.2 m) above combustion chamber roof

Thickness imhes/mm (Minimum)

° Walls Lining

4/102 ~/16 12/305 5/~/16

see 4-5

as lhted

4/102 4~/114 1 8/203 %/16

4/102 41/6/114

81203 sA/i6

Termination feet/m

(Minimum)

3/.92 above roof 2/:61 above any portion of any building within 10 ft. (3.1 m)

See Appendix D.

3/.92 above roof 2/.61 above any portion of any building within 10 ft. (3.1 m). See Appendix D.

10/3.1 higher than any portion of any building within 25 ft. (7.63 m)

(continued)

OiL

[8£

(Appendix C continued )

Chimney Service

Incinerators

Chute Fed

Combined hearth and grate area 7 sq. ft. (.65 m 2) or lessl Metal with fire brick lining laid in fire-clay mortar for full height of chimney Factory Built

Combined hearth and grate area more than 7 sq. ft. (.65 m2): Metal with fire brick lining laid in fire-clay mortar for full height of chimney Factory Built

Commercial and Indtmtrial Types

Solid masonry units or reinforced concrete with fire brick lining laid in fire-clay mortar for full height of chimney

Rubble stbne masonry with similar lining

Metal with similar .lining

Factory Built

Thickness. imhes/mm (Minimum)

Walls Lining

i i

see 4-1 4a~/114 as listed

see 4-1 4 a/6/11.4 as listed

8/203 4 ~ / 1 1 4

12/305 4½/114 see 4-1 41/6/114

as listed

Termination feet/m

(Minimum)

3/.92 above roof 2/.61 above any portion of any building within 10 ft. (3.1 m) See Appendix D.

10/3.1 higher than any portion of any building

' within 25 ft. (7.63 m)

% ' ~ 10/3.1 higher than any

portion of any building within 25 ft. (7.63 m)

:z

.<

:z

I=

0

0

, ,

m - t

~r~. . ~.g ~ N

N

. . . j

211--48 C H I M N E Y S , F IREPLACES~ AND VENTS

l & . . . . J = _ lr~ _ - - _ ~ . . . . .;I

~ MORE.THAN*10' (3.1 m) " ~ ' -

t~-,o. ,3., ° , - - - - ~ I~'%~?,%=? N~.

R,ooE / , . .o,.M,N.

I I , CHIMNEY 3' (,92 m) t i !1. - ' . ~ , , . ~ " I I I I T Y P E L VENT

, ; i i ~~,,~ !_Ii_±

' ~ MORE THAN 10' (3.1 m),~--4P

], CH,MNEY ~' (.9~ ~.) M,.. ~ r - - GAS VENTOR /

~::~" . TYPE L VENT 1 . ] I ' ~ L ~ 2' ('61 m) MIN" i

i--i

~il NOTE: i ' . '~ : NO HEIGHT ABOVE i ."~ ~ PARAPET REQUIRED I , --p:' WHEN OISTANCE FROM j~'*I~LJ ~i~ WALLS OR PARAPET ~ 1 / ~ MORE THAN 10' (3.1 m) HIMNEY OR VENT

WALL OR PARAPET

T e r m i n a t i o n more than 10 feet (3.1 m ) from r i dge , wal l or parapet .

A P P E N D I X E 211-49

Appendix E Referenced Publications

This Appendix is not a part o] this N F P A Standard for Chimneys, Fireplaces, and Vents, N F P A ~11-1977, but is included for information purposes only.

/

E-1 NFPA Standards. This publication makes reference t o the follow!ng NFPA codes and standards and the year dates shown indicate"the latest editions available. All these publications may be obtained by ordering them from the Publications Department, National Fire Protection Association, 470 Atlantic Avenue, Boston, MA 02210.

(a) NFPA Equipment

(b) NFPA

(c) NFPA

3,1-1974, Standard -fo( the Installation o-f Oil Burning

54-1974, National Fuel Gas Code

82-1972, Standard on Incinerators and Rubbish Handling ~"

(d) N F P A 96-1976, Standard -for the installation of Equipment .for the Removal of Smoke and Grease-Laden Vapors-from Commercial Cooking Equipment.

(e) NFPA 97M-1972, Glossary of Terms Relating to .Heat Pro- ducing Appliances

E-2 Other Codes and Standards. This publication makes. reference to the following codes ahd standards and the year dates shown indicate the latest editions available~

• (a) ASTM A167-1974, Specifications. for Stainless and Heat- Resisting Chromium-Nickel Steel Plate, Sheet, and Strip, American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103.

(b) ASTM A4.78-1970, Specifications-for "Chromium-Nickel Stain- less and Heat-Resisting Steel Weaving Wire, American Society for Testing and Materials, 1916 Race Street, Philadelphia; Pennsyl- vania 19103.

(c) ASTM.C64-1972, Specificati'ons -for Refractories .for Incinerators" and Boilers, American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103. O0

t ~

!

211-50 C H I M N E Y S , F I R E P L A C E S ~ A N D V E N T S

(d) ASTM C105-1971, Specifications .for Ground Fire Clay as a Refractory Mortar .for Laying-Up Fireclay Brick, American Society for Testing and Materials, 1916 Race Street, Philadelphia, Penn- sylvania 19103.

(e) ASTM C315-1970, Specifications for Clay Flue Linings, Amer- ican Society for Testing and Materials, 1916 Race Street, Philadel- phia, Pennsylvania 19103.

(f) Handbook Equipment 1975, American Society of Heating, Refrigerating and Air Conditioning Engineers, Inc., 345 East 47th Street, New York, New York 10017.

report of the committee on chimneys and other heat and

Documents