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Report of the Committee on Technical Committee on

Boiler Combustion System Hazards

Technical Correlating Committee

Dale E. Dressel, Chair Monsanto Co., MO [U]

Merton W. Bunker, Nonvoting Secretaey Nat'l Fire Protection Assn., MA

Courtney D. Alvey, Baltimore, MD [SE] Terry Michael Barrels, Kansas City Power & Light Co., MO [U]

Rep. Edison Electric Inst. Johnny W. (Bill) Bass, Forney Corp., TX [M] J~hmes 1L Bostick, Bailey Controls Co., OH [M]

addeus Bnkowski, Underwriters Laboratories Inc., IL [RT] William E. Cunningham, Jr., Raytheon Engr & Constructors, MA

[SE] ohn C. deRuyter, The DuPont Co., DE [U] obert S. Elek, Kemper Insurance, OH [I]

Ronald E. Frlngell, M&M Protection Consultants, OH [I] Steven IL Funk, The DuPont Co., TX [U]

Pep. American Petroleum Inst. Gordon G. Gaetke, Union Carbide Corp., WV [U] Masaaki Kinoshita, Mitsubishi Heavy Industries Ltd, Japan [M] Donald J . L. Lin, Qilin Inc., TX [SE] Francis X. Maskol, Honeywell, Inc., GA [M] Russell N. Mosher, American Boiler Mfrs. Assn., VA [M] JerryJ. Moskal, ABB Combustion Engr Inc., CT [M] Michael C. Polagye, Factory Mutual Research Corp., MA [I] Nancy C. Polosky, Babcock & Wilcox, OH [M] George P. Seroka, The Detroit Edison Co., MI [U] ames L. Sherman, Baltimore Gas & Electric Co., MD [U] eterJ. Gore Willse, Industrial Risk Insurers, CT [I]

Henry K. Wong, Foster Wheeler Energy Corp., NJ [M]

Alternates

Tetsuya Fujino, Mitsubishi Heavy Industries America, Inc., CA [M] (Alt. to M. Kinoshita)

Raymond J. Heitland, Monsanto Co., FL [U] (Alt. to D. E. Dressel)

Dennis P. Jenkins, Kemper Nat'l Insurance Cos., NC [I] (/kit. to R. S. Elek)

Gerald E. McCullion, Honeywell Inc., PA [M] (Air. to F. X. Maskol)

John P. O'Rourke, ABB Combustion Engr Inc., CT [M] (Alt. toJ . J . Moskal)

Richard J . Wachter, Industrial Risk Insurers, CT[I] (Voting Alt. to IRI Rep.)

J. C. Waung, Babcock & Wilcox Co., OH [M] (Alt. to N. C. Polosky)

Harold IL Yates, Detroit Edison, MI [U] (Alt. to G. P. Seroka)

William G. Yeich, Exxon Research and Engr Co., NJ [U] (Alt. to S. K. Funk)

Nonvoting

William H. Axtman, Gray Gull Assoc., Inc., VA Sheiton Ehrlich, Paio Alto, CA Thomas B. Hamilton, Hamilton Consulting Services, NC Robert P. Kaltenbach, Burns & McDonnell Eng, MO [SE] Peter B. Matthews, Hartford Steam Boiler Insp & Ins Co., CT

Committee Scope: This Committee shall have primary responsibility for documents on the reduction of combustion system hazards in single- and multlple-burner boilers with a heat input rate of 12,500,000 Btu/hr and above. This includes all fuels. This Committee also is responsible for documents on the reduction of hazards in pulverized fuel systems, fluidlzed-bed boilers, heat recovery steam generators, and stoker-fired boilers, at any heat input rate.

Multiple Burner Boilers

Robert P. Kaltenbach, Chair Burns & McDonnell Eng, MO [SEJ

Francis X. Maskol, Secretar 3 Honeywell, Inc., GA [M]

Samuel H. Allen, Dow Chemical U.S.A., LA [U] Courtney D. Alvey, Baltimore, MD [SE] Johnny W. (Bill) Bass, Forney Corp., TX [SE] Thomas A. Collette, Commonwealth Edison, IL [U] Dale E. Dressel, Monsanto Co., MO [U] ~.~ hn J. Eibi, DuPont Engr, TN [U]

• C. Gery, Doylestown, PA[SE] Bernard Hrul, Allen Bradley Co., OH [U] George Y. Keller, Burns & Roe Enterprises, Inc., NJ [SE] Blair E. Kerstetter, The Foxboro Co., MA [M] DanlelJ. Lee, Bailey Controls Co., OH [M] W. Scott Matz, Triconex Corp., "IX [SE] Pete McKenna, Stone & Webster, MA [SE] Lalit M. Mehta, Coen Co., Inc., CA [M] Edward G. Milone, Consolidated Edison of New York, NY [U] Russell N. Mosher, American Boiler Mfrs. Assn., VA [M] ohn P. O'Rourke, ABB Combustion Engr Inc., CT [M] rancisco A. Palacios, DB Riley, Inc., MA [M]

Michael C. Polagye, Factory Mutual Research Corp., MA [I] PeterJ. Gore Willso, Industrial Risk Insurers, CT [I] Henry IL Wong, Foster Wheeler Energy Corp., NJ [M] Harold IL Yates, Detroit Edison, MI [U] Allan J. Zadiraka, Babcock & Wilcox, OH [M]

Alternates

John E. Bolllnger, Babcock & Wilcox, OH [M] (Alt. to A. J. Zadiraka)

John C. deRuyter, The DuPont Co., DE [U] (Alt. to J. J. Eibl)

Raymond J. Heitland, Monsanto Co., FL [U] (Air. to D. E. Dressel)

W. J. Johnson, The Dow Chemical Co., TX [U] (Alt. to S. H. Allen)

Jerry j . Moskai, ABB Combustion Engr Inc., CT [M] (Alt. to J. P. O'Rourke)

Billy L. Smith, Jr., Burns & McDonnell Engr Co., MO [SE] (AIt. to R. P. Kaltenbach)

Nonvoting

Thomas C. Clayton, Black & Veatch, MO Robert M. Lundberg, Los Altos, CA

(Member Emeritus)

Staff Liaison: Merton W. Bunker, Jr.

Committee Scope: This Committee shall have primary responsibility for documents covering the reduction of combustion system hazards and the prevention of boiler furnace explosions and implosions in m . tiple burner boilers with a heat input rate of 12, 500,000 Btu/hr and above. This includes all fuels.

These lists represent the membership at the time each Committee was balloted on the text of this edition. Since that time, changes in the membership may have occurred. A key to classifications is found at the back of this document.

The Report of the Committee on Boiler Combustion System Hazards is presented for adoption.

This Report was prepared by the Technical Committee on Mutiple Burner Boilers, and proposes for adoption amendments to NFPA 8502-1995, Standard for the Prevention of Furnace Explosions/Implosions in Multiple Burner Boilers. NFPA 8502- 19~5 is published in Volume 9 of tile 1997 National Fire Codes and in separate pamphlet form.

This Report has been submitted to letter ballot of the Technical Committee on Mutiple Burner Boilers, which consists of 25 voting

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members. The results of the balloting, after circulation of any negative votes, can be found in the report.

This Report has also been submitted to letter ballot of the Technica/Correlatlng Committee on Boiler Combustion System Hazards, which consists of 24 voting members; of whom 22 voted affirmatively, 1 negatively after circulation of negative ballots (Mr. Willse), and 1 abstained (Mr. Cunningham)°

Mr. Wiilse voted negatively stating: "8502-1b (Log #CP8): ff there is information in the appendix that

is indeed viable to the design of boilers, then this information must be in the body of the standard. We have been directed to remove all unenforceable language, yet we are now adding some by stating "...the user of this standard shall be familiar with...", ff we want to draw the reader's attention to the appendix information, this can best be done in the Foreword."

"8502-44a (Log #CP6) and 8502-57 (Log #53): We are adding an Exception to the sections dealing with igniters. In it we are stating they can use "indirect monitoring" yet we do not explain what "indirect monitoring" is. In addition, in the last sentence of the Committee Statement it states "In this case, the authority having "urisdiction should be satisfied that reasonable supervision is Jprovided." If we indeed mean the authority having jurisdiction needs to be satisfied, then we must first state: "Where acceptable to the authority having jurisdiction, igniters with a capacity of five million Btu/hr or less shall be permitted to have indirect monitoring of the valve position." And indicate what is indirect monitoring."

"8502-72 (Log #8): The sketch show the Low Pressure Switch on the oil line for igniters has been removed. Table 7-5.2.5.2(a) requires a mandatory fuel trip if the fuel and atomizing medium is outside the operating limits. We need to keep the low oil pressure switch on the sketch. Figures A-7-81 and A-7-81I for manual systems has the oil pressure switch. If this proposal passes, the only boiler that would not require the low oil pressure switch would be the supervised manual boiled"

Mr. Cunningham abstained stating: "On Log #51, I have to agree with Mr. Alvey's comment on

proper fuel/air ratio at each burner during start-up. This is very tmportant with the two burner units. It does not require an automatic control but as an operator checkpoint during start."

"On Log #8, it appears that the low pressure or differential switches are being removed on supervised manual systems and being replaced with a gauge. Gauges do not trip boilers."

Mr. Alvey voted affirmative stating: "I am voting ~Aitirmative" to release the Report, but I intend to

submit a comment on Proposal 8502-15, Section 4-5, which will reflect my negative vote on the Technical Committee ballot."

Mr. DeRutyer voted affirmative stating: "1 agree with the negative comments on Log #CP8, Log #54, and

the negative comments on Log #CP6 and Log #53 relative to the need for an explanation of "indirect monitoring". Comments will be submitted when appropriate testing."

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N F P A 8502 - - F98 R O P

(Log #CP7) 8502- 1 - (Chapter 1): Accept SUBMITTER: Technical Committee on Multiple Burner Boilers RECOMMENDATION: Make the following changes to Chapter 1:

In Section 1-1.5 delete the words "considered ~ and "and reasonable" in the second sentence.

In Section 1-2.2 revise the beginning of the first sentence to read: "No standard guarantees ...'. In Section 1-2.3 delete the words "adequate" and "proper" in all

places. Revise Section 1-2.4 to read as follows: "Gas cleanup systems located downstream of the post-

combustion gas passes of the boiler furnace shall be coordinated with the operatingprocedures and design of the boiler furnace system. Such coordination shall include requirements for ensuring a continuous flow path from the forced draft fan inlet through the stack. This standard provides only the general requirements for these systems because of the multiplicity of their designs." SUBSTANTIATION: Revisions were made to remove unenforceable language in Chapter 1. COMMITTEE ACTION: Accept. NUMBER OF COMMrlWEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #40) 8502- l a - (1-1.1 and 1-1.2): Accept SUBMITTER: JohnJ . Eibl, DuPont RECOMMENDATION: Revise Section 1-1 Scope as follows:

1-1.1 This standard shall apply to boilers with a fuel input rating I of 12,500,000 BTU/hr. (~663kW) or greater. This standard applies ] to multiple burner boilers firing one or more of the following: ] (a) Fuel gas, as defined in Chapter 3, b) Fuel oil, as defined in I Chapter 3, and c) Pulverized coal, as defined in Chapter 3. [ 1-1.2 This standard indudes simultaneous firing of more than I one fuel.

SUBSTANTIATION: Suggested revisions to Chapter 1 to facilitate the option of burning more than one fuel simultaneously in a boiler. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #CP8) 8502- lb - (1-1.10 (New)): Accept SUBMITTER: Technical Committee on Multiple Burner Boilers

] RECOMMENDATION: Add a new Section as follows: 1-1.10 The appendices contain information viable to the design

[ and understanding of this standard. Therefore the user of this I standard shall be familiar with the contents of the appendices.

SUBSTANTIATION: This section brings the importance of the endlx material to the attention of the users of this standard.

TTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 24 NEGATIVE: 1

EXPLANATION OF NEGATIVE: WILLSE: If there is information in the appendix that is indeed

viable to the design of boilers, then this information must be in the body of the standard. We have been directed to remove all unenforceable language, yet we are now adding some by stating "...the user of this standard shall be familiar with...". If we want to draw the reader's attention to the appendix information, this can best be done in the Forward.

(Log #50) 8502- 2 - (3.1 Coal Fuel Trip (New), Gas Fuel Trip (New), Igniter Fuel Trip (New), and Oil Fuel Trip (New)): Accept SUBMITrER: Thomas A. Collette, Commonwealth Edison

I RECOMMENDATION: Add the following new definitions to Chapter 3:

C.~al Fuel Trio. An event resulting in the raDid shutoff of all coal v

fuel while other fuels being fired remain in service. Gas Fuel Trio. An event resulting in the raoid shutoff of all ~as

ftl¢l while other fuels being fired remain in service. Igniter Fuel Trio. An event resulting in the raoid shutoff of all

igniter fuel while other fuels being fired remain in service. Oil Fuel Trip. An event resulting in the raoid shutoff of all oil

fuel while other fuels bein~ fired remain in ~ervice, v

SUBSTANTIATION: Required for changes to incorporate revisions for multi-fuel firing. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #49) 8502- 3 - (3-1 Master Fuel Trip): Accept SUBMITTER: Thomas A. Collette, Commonwealth Edison RECOMMENDATION: a. Revise the definition of Master Fuel Trip in Chapter 3 to read as follows:

Master Fuel Trip.* An event resulting in the rapid shutoff of all fuel, including igniters.

b. Add the following to Appendix A: A-3.1 Master Fuel Trin. On multlnle fuel fired installations.

individual fuel trins CGas Fuel Trin.'Oil Fuel Trio. & Coal Fuel Trio~ can 9ccur without necessarily resulting in a Master Fuel Trio unless all fuel is triooed or stoooed. SUBSTANTIATIOiq-: Required-for changes to incorporate revisions for multi-fuel firing. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #41) 8502- 3a - (4-1.1.1, A-4-1.1 (New)): Accept in Principle SUBMITTER: S.H. Allen, Dow Chemical U.S.A RECOMMENDATION: Add statement of caution to follow Paragraph 4-1.1 as follows:

"Caution: Furnace design pressures greater than those specified in Section 4-1.1.1 could result in a home service energy release upon failure of the furnace enclosure, should a fuel explosion O c c u r " .

SUBSTANTIATION: This statement will alert the user to the concerns of excessive positive furnace pressure design. COMMITTEE ACTION: Accept in Principle.

[ Add the caution statement as modified below to appendix section I A-4-1.1: ] Caution: Furnace design pressures greater than those spedfied in [ Section 4-1.1.1 could result in a more severe energy release upon I failure of the furnace enclosure, should a fuel explosion occur.

COMMITTEE STATEMENT: The proposed material contains unenforceable language and is more appropriate as appendix material. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #46) 8502- 4 - (4-2.1): Accept SUBMITrER: Harold R. Yates, Detroit Edison RECOMMENDATION: In the third line, change ~fuel" to "fuel (s~". SUBSTANTIATION: Required to match with revised simultaneous fuel firing. COMMITYEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

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N F P A 8 5 0 2 ~ F 9 8 R O P

(Log #47) 8502- 5 - (4-2.3.2(a)1): Accept SUBMITTER: Harold R. Yates, Detroit Edison RECOMMENDATION: In the second line, change "fuel" to "fuel.~". SUBSTANTIATION: Required to match with revised simul~meous fuel firing. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #48) 8502- 6 - (4-2.3.2(b)2): Accept SUBMITTER: Harold R. Yates, Detroit Edison

I RECOMMENDATION: In the third line, change "fuel" to "fi, el .(.O.". SUBSTANTIATION: Required to match revised simultaneous fuel firing. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #54) 8502- 7 - (4-2.3.2(d)10): Accept in Principle SUBMITTER: Joan Kraiza, ABB Combust ion Engr Inc. RECOMMENDATION: Recommend the following wording to 4- 2.3.2(d) 10:

"Igniters shall be permanent ly installed and supervised for igniter flame. Class I and II igniters shall be individually supervised to verify that capacity requirements , as out l ined in Chapter 3, 4- 2.3.2(d)1 and (d)2 are met. This supervision shall be accomplished by means of pressure, differential pressure, flow, or otber devices which reliably prove that the igniter is operating at its rated capacity.

Caution: The means of supervision of igniter capacity must provide adequate protect ion for applications where the igniter tip is subject to ~,luggage due to such p h e n o m e n o n as tip fouling, slagging, etc . ' SUBSTANTIATION: The proposed changes to the subject paragraph s t rengthen the requi rement for supervision of igniter capacity and ensures that dais supervision is no t subject to false indications. COMMITTEE ACTION: Accept in Principle.

] Modify Section 4-2.3.2(d)10 to read as follows: I 10. Igniters shall be pe rmanendy installed. They shall be ] supervised to verify that the requirements of 4-2.3.2(d)1 and 4- ] 2.3.2(d)2 are met. Tltis supervision shall include igniter capacity ] and individual igniter flame monitor ing. The capacity shall be ] measured by igniter header pressure as a minimum.

COMMITTEE STATEMENT: The revised wording clarifies the Committee 's intent. Capacity moni tor ing is required for all classes of igniters and may be at the header radaer than at each igniter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: EIBI~ After fur ther consideration, I take exception to the

statements requiring supervision of capacity on all igniters: The submitter 's a rgument for the original p roposed wording was

to s t rengthen the requi rement for supervision and capacity verification on Class I and Class II igniters. Her substantiation was concern over false indications and the potential for igniter tip fouling.

Monitor ing header pressure does no t address concerns over igniter fouling and deal primarily with oil igniters. Also, Sections 4-2.3.2(d) 1 recjuires igniters to be verified by test to assure they mee t the. requirements, of the i gniter, class sp ecitied in the design . Class III igmters should not be r eqmred to have supervision o f capacity. Tbeir durat ion of operat ion typically results in less than 25 percent of the LEL concentrat ion when purge airflow is maintained. There are several safety interlocks to shutdown the main burner should it fail to light dur ing the main Trial For Ignition.

MEHTA: It is my belief that the Commit tee in tended to exclude Class III igniters from the requirements for supervision of die

capacity as Class III igniters are in service for maximum of 30 seconds.

(Log #10) 8502- 8 - (4-2.3.2(d)4): Accept in Principle SUBMITTER: Bill Bass, Fomey Corp. RECOMMENDATION: Add "is" after "the igniter". Text will now read as follows:

"4. Where Class 3 igniters are used, the igniter shall be turned off as a part of the burner light-off procedure when the time trial for ignition of the main burner has expired." SUBSTANTIATION: Editorial change. Word omitted in last revision. COMMITTEE ACTION: Accept in Principle.

Revise the recommenda t ion as follows: Add "shall be" after "the igniter". Text will now read as follows: 4. Where Class 3 igniters are used, the igniter shall be turned off

as a part of the burner light-off p rocedure when the time trial for ignition of the main burner has expired. This practice ensures that the main flame is no t d e p e n d e n t on ignition support from the igniter. COMMITTEE STATEMENT: The Commit tee replaced "is" with "shall be" to conform with the manual o f style. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #11 ) 8502- 9 - (4-3.2.2(g)): Accept in Principle SUBMITTER: Bill Bass, Forney Corp. RECOMMENDATION: Change this paragraph to read:

"Any single componen t failure within the logic system shall no t

~ revent the automatic occurrence of a mandatory master fuel trip". UBSTANTIATION: Some system designers take the position

that since there is a hardwired switch direct to tile master fuel trip relay, the operator can always trip tile uni t and there does not need to be any fur ther protection against failures. This is a poor a rgument as it relies on an alert opera tor to immediately recognize and evaluate a problem. If, for example, a critical trip input channel to the BMS were to fail, it is unlikely that the operator would immediately know. Even if they were to be aware of it, they would have to moni tor other signals to de termine if they were in an unsafe condit ion and then make a decision as to whether they should trip the unit. It is unlikely they would immediately r emember the exact trip set point of the process in question. The new wording will require the BMS design to automatically generate a master fuel trip even in the event of a single point failure. COMMITTEE ACTION: Accept in Principle.

Revise the text of Section 4-3.2.2(g) to read as follows: "No single componen t failure within the logic system shall

prevent the actions required by Sections 6-5.2.5, 7-5.2.5 and 8-5.2.5 for the mandatory master fuel trips." COMMITTEE STATEMENT: The revised wording more clearly defines the intent of this paragraph and meets the intent of the submitter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #12) 8502- 10 - (4-3.2.2(0): Accept in Pr indp le SUBMITTER: Bill Bass, Forney Corp. RECOMMENDATION: Add a new paragraph

(i) Failure of any device within the logic system which could ultimately have an impact on the automatic occurrence of a master fuel trip shall be alarmed. SUBSTANTIATION: A single point failure is not allowed to prevent a master fuel trip. If any single point does fail, that failure should be alarmed so that it can be corrected before a second failure occurs that may prevent the occurrence of a master fuel tri lp. COMMITTEE ACTION: Accept in Principle.

Add to tile end of the paragraph of Section 4-3.2 the following: "Alarms shall be genera ted to indicate equ ipment malfunction,

hazardous conditions, and misoperation. T h e primary concern is to alarm conditions that pose a threat of impending or immediate hazards."

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N F P A 8 5 0 2 - - F9 8 R O P

COMMITTEE STATEMENT: The revised wording meets the intent of the submit ter and is consistent with similar wording in o ther sections of the standard. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #55) 8502- 11 - (4-3.2.20) (New)): Reject SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Add new text to read as follows:

(i) The Burner Management System design shall be in accordance with ANSI/ISA $84.01. SUBSTANTIATION: Added to require compliance with ANSI/ISA $84.01 which refer to OSHA 29CFR 1910. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: It is no t necessary for this s tandard to reference or require the use of other standards which is the

ruerogative of the authority having jurisdiction. MBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25

VOTE ON COMMITTEE ACTION: AFFIRMATIVE: 25

(Log #97) 8502- 12 - (4-3.2.3.3): Reject SUBMITTER: Gordon Gaetke, Union Carbide Corp. RECOMMENDATION: Replace 4-3.2.3.3 The logic system shall be limited to one boiler only.

With: 4-3.2.3.3 Segregated safety logic systems shall be considered for

multiple boilers in order to provide cont inued steam product ion dur ing boiler main tenance and periodic logic system functional tests. This segregation is required to meet the logic protect ion requirements of Section 4-3.2.2(d) while maintaining steam

~ roduct ion. UBSTANTIATION: Current microprocessor based logic system

technology provides dual and triplicate r edundan t logic solvers with capability to reliably perform emergency shutdown (ESD) functions for multiple equipment . System diagnostics with fault detect ion can provide (1) uni t shutdown (dual processor) to assure a fail-s,xfe system such that a single point failure will not result in an unsafe condit ion or (2) automatic logic system identification of a failed componen t without loss of protect ion or requir ing automatic shutdown of the boilers (triple modular redundancy technology).

The logic system; however, must allow for maintenance and periodic functional tests of the emergency shutdown system without compromising boilers that continue to operate. Segregation of ESD systems must be based on the number of boilers required for cont inuous steam product ion during such maintenance and functional testing.

Separation of Basic Process Control Systems f rom Emergency Shutdown (ESD) systems is a fundamenta l requi rement in the Ins t rument Society of America industry standard, ISA-S84.01 "Application of Safety Instruhaented Systems for the Process Industries", newly issued February 1996. Such is believed to be the intent of the committee. ISA-S84.01, which provides a more complete guide to the correct implementat ion of Safety Logic Solver systems, permits the use of a single ESD system for multiple equipment . Such applications are safely practiced by industry (e.g., Olefins furnaces, Distillation Columns, Chemical Reactors, etc.). COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: NFPA 8502 does no t require or specify the same requirements as an ESD as def ined by ISA Standard $84.01 and therefore the committee believes limiting the logic system to one boiler provides increased safety and maintainability. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #51) 8502- 1B - (4-5): Accept in Principle SUBMI'FrER: Herb Gery, Doylestown, PA RECOMMENDATION: Replace existing Section 4-5 with the following:

4-5 Combustion Control System. 4-5.1 Functional Requirements. 4-5.1.1 The combustion control system shall regulate the fuel

and air inputs into the furnace to maintain the a i r / fuel ratio within a range that shall assure cont inuous combustion and stable flame under all operat ing conditions.

4-5.1.2 Where applicable, the furnace draft control shall be included in the combustion control system. (See Chapter 5)

4-5.2 System Requirements. 4-5.2.1 Whenever the fuel d e m a n d is less than the purge rate the

combust ion control system shall maintain total air flow at the purge rate. Safe and stable a i r / fuel ratios shall be mainta ined at each fired burner.

4-5.2.2 In the event that the measured total fuel input is greater than the air flow demand, the combustion control system shall reduce the fuel input until a proper a i r / fuel ratio has been restored. Air flow shall not be increased automatically, but the condit ion shall be alarmed. (See paragraphs 6-5.3.2, 7-5.3.2 or 8- 5.3.2 for constraints)

4-5.2.3 In the event that the measured total air flow is less than the fuel demand, the combustion control system shall reduce the fuel demand until a proper a i r / fuel ratio has been restored. Air flow shall not be increased automatically, but the condi t ion shall be alarmed. (See paragraphs 6-5.3.2, 7-5.3.2 or 8-5.3.2 for constraints)

45.2.4 Measurements of furnace inputs and outputs shall be sufficiently accurate and reproducible to maintain stable firing conditions to meet the control criteri3. Pressure, temperature, density a n d / o r viscosity corrections shall be employed, as applicable to meet this requirement .

4-5.2.5 When multiple fuels are fired, the fuel inputs shall be totalized in the basis of their relative heat values.

4-5.2.6 The total heat input to a given burner or furnace zone shall not exceed the maximum limits specified by the boiler manufacturer .

4-5.2.7 Means shall be provided to enable the operator to adjust the air / fuel ratio. The span of the adjustment shall be appropriate to the fuel(s) being f ired. Consideration shall be given to continuous on-line analysis of the oxygen, combustibles and carbon monoxide content of the flue gas stream for use as an operating guide and for control.

4-5.2.8 The equipment selection and the design of the combustion control system shall facilitate the calibration, testing and maintenance requirements described in Chapter 9.

4-5.3 Interlocks. 4-5.3.1 The burner management system shall take precedence

over the combustion control system. The supplier of the burner management system shall establish safety limits within which the combust ion control system shall be required to operate.

4-5.3.2 Where applicable, automatic control of air flow shall not be permit ted unless the furnace draft control is maintained in automatic.

4-5.3.3 Automatic control of the fuel input(s) shall not be permit ted unless the air flow is mainta ined in automatic.

4-5.3.4 Automatic control of the coal feed to a pulverizer shall not be permit ted unless the associated outlet tempera ture and primary air flow controls are mainta ined in automatic at the values established by the pulverizer manufacturer . The combustion control system shall no t automatically reduce the coal feed to a pulverizer below the min imum value established by the pulverizer manufacturer .

4-5.3.5 The combustion control system shall nei ther automatically increase nor decrease a fuel input if the change would result in unsafe or unstable bu rne rp r e s su re as de te rmined by the burner manufacturer. Whenever a decrease in a fuel input is blocked, a decrease in air flow shall also be blocked. SUBSTANTIATION: My original objective was to de termine what impact, if any, the inclusion of multiple fuel firing would have on the present Section 4-5 "Combustion Control System". While I suspected t h a t a d d i n g a few "(s) ' s here and there would no t suffice, I did not appreciate how dated this section has become. After all, it has not been upda ted for over eleven years. During that eleven years the equipment available and the operating requirements of combustion control systems have significantly changed." Some of the more significant developments in combustion control systems are:

1. Microprocessor-based equ ipmen t dominates new construction. Some years ago this commit tee labored long and hard to update Section 4-3 to accommodate microprocessors for

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bu rne r m a n a g e m e n t systems. So detai led a ch:mge is no t requi red for the combt,s t ion control system. However, the present language is o r ien ted tow~u'd pneuma t i c systems and is dated. For example , I defy you to find a "g:Ls flow meter" in a m o d e r n power plant. Just as tile Bible is update to accommoda te our evolving language, this "bible" should reflect cu r ren t usage. T he changes in wording that I have p roposed are compat ible with both pneuma t i c a n d micro proccessor-based systems.

2. Low excess air and off-stochionmtric opera t ions are now commonplace . As a result, p roper air dis t r ibut ion is more critical. This can only be achieved with more accurate mid reproducible m e a s o r e m e n t s of both fuel inputs a n d die combus t ion air supply. Whcn lnore s t r ingent operat ing requ i rements are imposed, the combus t ion control system des igner mus t observe greater care in tim process variable calculations. My sugges ted revised pa ragraph 4-5.2.4 is more geueral than die existing text bu t caut ions die des igner to assure tha t all of the m e a s u r e m e n t s ,are consis tent a n d compat ible with the corluo] strategy. The in tent is no t to over design for systems that do no t require such at tent ion. Rather, tile in ten t is to assure that the m e a s u r e m e n t s shall no t be u n d e r des igned when greater care is warranted.

3. Oxygen and carbon monox ide analyzers have become more reliahle a n d as a result, are more acceptable. Automat ic ()z control shou ld not be manda to ry where it is no t warranted. However, die commi t tee should be positive in endors ing ()~ a n d CO control where it is appropria te . (Paragraph 4-5.2.5) Automat ic com'ection of excess air is manda to ry when low excess air operat ion is employed.

4. Today, many boilers operate at r educed load at night. It is clearly the conn1~ittec's intcti t tha t air flow sludl no t be reduced below purge rate wht:n tile firing rate is reduced. However paragraph 4-5.2(a) ot the present text implies that dfis r equ i r emen t applies to "start-up conditions". My r e c o m m e n d e d paragraph 4- 5.2.1 is more compat ib le with the commit tee ' s in tent mid the rest of die s tandard.

And finally, we c onm to the reason why we reviewed Section 4-5 in the first place:

5. Ill mos t cases, nluhi[~le fuel f ir ing will be governed by economics , this means ttmt one fuel or the o ther will most likely operate at or near its m a x i m u m or m i n i m u m limits. The comnli t tee shou ld express concern for the l ikelihood tha t die combus t ion control system design could drive tile file] into unsafe or uns table f ir ing condit ions. Proposed paragraphs 4-5.3.4 a n d 4- 5.3.5 requires interlocks that are ab'eady in c o m m o n use a n d which should be inaud;itOl'y. COMMITTEE ACTION: Accept in Principle.

Change the proposed r e c o m m e n d a t i o n to read as follows: Replace existitJg Section 4-5 with die following: 4-5 Combus t ion Corttrol System. 4-5.1 Function:d Re¢luirements. 4-5.1.1 The contt mst lou control system shall regulate die filel

and air inputs into the tu rnace to mainta in the air / f iml ratio within a r m a g e that shall assure con t inuous combus t ion mad stable f lame u n d e r all opera t ing condit ions.

4-5.1.2 The furnace draft control shall be coordina ted widl t im combus t ion control system.

4-5,2 System Requirements . 4-5.2.1 1Jnder no c i rcumstances shall t he airflow d e m a n d be less

d lan the purge rate. 4-5.2.2 The fuel d e m a n d shall no t increase tile fuel input(s)

above the awlilahle airflow. 4-5.2.3 Airflow dem,'uid shall no t reduce airflow below flint

requh 'ed hy the actual fuel input(s) . 4-5.2.4 The fi~el demancl shaU no t exceed die capability of the

opera t ing draft fans. Should the loss or slmt-down of a draft fan cause die fuel d e m a n d to tie greater than the capacity of die fires in service, the fuel(s) shztl[ be rapidly r educed to a value that can be a c c o m m o d a t e d .

,1-5.2.5 Measn remen t s used in tile combus t ion control system shall he suff lciendy accurate and reproducible to main ta in stable firing condit ions. Pressure, t empera ture , densi ty a n d / o r viscosity correct ions shall he employed, as applicable to mee t this requiren~eut.

,1-5.2.0 When rnulti ~le fuels are fired, file fitel inputs shall be totalized on tile h;t~is of the r re ative hea t values.

4-5.2.7 T h e total hea t i~tput to a given burner or fur 'nace zone shall no t exceed the max imun l limits specified by the boiler n lanufacturer .

4-5.2.8 Means shall he provided to enable tile opel,'ator to adjust tile a i r / fue l ratio. Tile Spill of the ad j u s t men t shall be appropr ia te to the fuel(s) he ing fired. Considera t ion sh:dl be given to cotitiHuous oil-line analysis of tile oxygen, combust ib les and Cal'hon ulonoxide coli tent of tile title g,'LS strealn for use as an opera t ing guide and for control.

4-5.2.9 The e q u i p m e n t selection and the design of the combus t ion control system shall facilitate the on-line calibration, test ing and ma in t enance requ i rements descr ibed in Chapter 9.

4-5.3 Permissives. 4-5.3.1 Any logic c o m m a n d s f rom the b u r n e r m a n a g e m e n t

system shall take p recedence over the combus t ion control system. 4-5.3.2 Where applicable, au tomat ic control of air flow shall no t

be permi t ted unless die fu rnace draft control is main ta ined in automat ic .

4-5.:3.3 Automat ic control of the fuel input(s) shall no t be permi t ted unless the air flow is ma in t a ined in automatic .

4-5.3.4 The combus t ion control system shall no t reduce the coal feed to a pulverizer below the m i n i m u m value establ ished by the pulverizer manufac turer .

4-5.3.5 The combus t ion control system shall ne i ther automatical ly increase nor decrease a fuel inpu t beyond the b u rn e r operat ing r ange as de t e rmined by the manufac tu re r an d verified by ope ra t ing test. COMMITTEE STATEMENT: The changes made mee t the in ten t of the submit ter . Editorial changes were made for clarity. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: ALVEY: I have n o p r o b l e m with the material covered in this

Proposal as m o d i f i e d b y die Commi t t ee except for what I consider a critical omission. The revised Section 4-5 nowhere includes the r e q u i r e m e n t in existing Section 4-5.2(a) for p roper fue l / a i r ratio at each bu rne r dur ing start-up. This is one of the key requ i rements of the open register light-off procedure , and has been inc luded in every previous edit ion of a mul t ip le -burner s tandard.

Since I agree wida all the rest o f this Proposal, I was going to vote "Affirnaative with Comment" , bu t I feel tha t dais is so impor tan t that a Negative Vote is required.

This Proposal could be made acceptable to me by inser t ing the words "and to each burner" after the word "furnace" in 4-5.1.1. COMMENT ON AFFIRMATIVE:

LEE: I tems 4-5.3.4 and 4-5.3.5 shou ld be moved to section 4-5.9. Pulverizer, oil, and gas d e m a n d deve lopmen t is a r e q u i r e m e n t a n d no t a permissive. For readability, i tems in section 4-5.2 could be rea r ranged by topics (i.e., air r equ i rements , fuel requi rements , m e a s u r e m e n t r equ i rements , others) .

(Log #4) 8502- 14- (5-4.3(d).4): Reject SUBMITTER: O. R. Tattoli, Amer ican Electric Power RECOMMENDATION: Add the following sen tence at tile end o f paragraph (d) 4:

The forced draft fans shall no t be t r ipped if d ie boiler is des igned to opera te with a posit ive fu rnace pressure. SUBSTANTIATION: Following a MFT, it is impor tan t to mainta in air flow to the furnace to both purge the furnace of u n b u r n e d combust ib les a n d con t inue to supply air mass to the fiwnace and thus mitigate the MFT furnace draft decay p h e n o m e n a . Depend ing on the severity of the fu rnace draft decay after a MVI', on loss of all ID fans, a furnace implosion could occur. Furnace structural damage caused by an implosion can be avoided if the FD fans are no t tr ipped.

A boiler des igned for pos i t ivepressure opera t ion with FD fan(s) only may be later retrofit ted with ID fan(s) . Therefore , dais boiler has all d ie fu rnace pressure opera t ion personne l protect ion systems in place a n d can safely withstand positive fu rnace pressure if FD fans are no t t r ipped after a MF'Y has been init iated on loss of ,all ID fans. COMMITTEE ACTION: Reject. COMMITTEE STATEIVIENT: T h e ID fan conversion e q u i p m e n t may no t have been des igned for positive pressure operat ion, a n d diere is no assurance tha t the integrity of positive pressure personnel protect ion is fully funct ional at the t ime of the trip. NUMBER OF COMMITTEE MElVIBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(8502-15 was not used)

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(Log #45) 8502- 1{5- (6-3.1.10): Accept SUBMITTER: Lalit M. Mehta, Coen Co., Inc.

I RECOMMENDATION: Revise text as follows: 6-3.1.10 Gaspiping material and system design shall be in

accordance with NFPA 54 National Fuel Gas Code ANSI Z223.1 for gas piping inside industrial and institutional buildings or ANSI B31.1 code forpressure piping-power piping as applicable. SUBSTANTIATION: ANSI B31.1 is not applicable to all situations. This clarifies that other standards may be more

E ACTION: Accept. NUMBER OF COMMrrTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #CP2) 8502- 19a - (6-5.2.1.1(o),7-5.2.1.1(p), 8-5.2.1.1(m) ): Accept SUBMITTER: Technical Committee on Multiple Burner Boilers RECOMMENDATION: Revise the last sentence of Sections 6- 5.2.1.1(o), 7-5.2.1.1(p) and 8-5.2.1.1(m) to add the word "uniC before the word "purge". SUBSTANTIATION: Committee intent is to require a purge of not less than 5 minutes, or five changes in volume of the boiler enclosure, whichever is longer. This is the definition of "Unit PurgC. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #33) 8502- 17 - (6-4.1): Accept SUBMITTER: Michael C. Polagye, Factory Mutual Research Corp.

I RECOMMENDATION: Third line: change %ralve" to Nralve(s)'. SUBSTANTIATION: An individual gas burner may have one or two valves. When two safety shut-off valves are provided, both shall be automatically closed. Consistent with text in other sections of chapter. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITI'EE ACTION:

AFFIRMATIVE: 25

(Log #36) 8502- 18 - (6-5.2.1): Accept SUBMITTER: George Y. Keller, Bums & Roe

I RECOMMENDATION: Revise Section 6-5.2.1 to read as follows: 6-5.2.1 Cold Start. This section covers the requirements for

placing gas in service as the initial fuel being fired. Section 6-5.2.{5 covers the requirements for placing gas in service as a subsequent fuel. " SUBSTANTIATION: This addition clarifies the difference between first and subsequent fuels. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #25) 8502- 19 - (6-5.2.1.1): Accept SUBM1TrER: John P. O Rourke, ABB Combustion Engineering,

n o .

RECOMMENDATION: In Section 6-5.2.1.1, replace existing subsections (f) through (m) with the following:.

"(F) Theprope r drum water level is established in drum-type boilers, andcirculating flow is established in forced drculauon boilers, or minimum water flow is established in once-through boilers.

(g) The oxygen and combustibles analyzers, if provided, are operatin~ satisfactorily and a sample has been obtained. Combustibles indication is at zero and oxygen indication is at maximum.

(h) All safety shutoff valves are closed. All sparks are deenergized.

(i) For oil ignition systems, see Chapter 7. (j) The fuel system vents are open and venting to atmosphere

outside the boiler room. Lines are drained and cleared of materials such as condensate.

(k) The burner elements and igniters are positioned in accordance with the manufacturer's specification.

(i) Energy is supplied to control systems and to safety interlocks. (m) The meters or gauges indicate fuel header pressure to the

unit." SUBSTANTIATION: Sections were renumbered to organize items for multiple fuel firing startup sequences. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITrEE ACTION:

AFFIRMATIVE: 25

(Log #32) 8502- 20- (6-5.2.1.3): Accept SUBMITTER: Henry FL Wong, Foster Wheeler Energy Corp. RECOMMENDATION: Revise text as follows:

1. Delete paragraph 6-5.2.1.3(c), renumber the paragraphs following (c) accordingly.

2. Reword paragraph presendy 6-5.2.1.3(0, to be renumbered 6- 5.2.1.3(e), changes are shown underlined.

6-5.2.1.3(e) The main fuel control valve shall be closed and the main safety shutoff valve(s) shall be opened. (See Sections 6-5.4.{5 for leak test retmirement and 6-6 for permissive conditions in the furnace purge ~stem that shall be satisfied before this can be accomplished.)

3. Add the following new paragraph, which is a modification of the deleted 6-5.2.1.3(c) changes are shown as strikethrough and underlined, prior to the present 6-5.4.6. Renumber paragraph 6- 5.4.6 to be 6-5.4.7.

6-5.4.{5 An operational leak test of the fuel header piping system shall be performed in accordance with established procedures while maintaining at least purge rate airflow. Successful completion of the leak test shall be p=.~ =f : :=r=.pl=:c~ u=it pcrgc done before placing the main ~ svstem into operation. [See Figure A-6-5.1.2(b) ]

4. Renumber existing 6-5.4.6 to 6-5.4.7. SUBSTANTIATION: Old text required a fuel gas system header leak test even if the unit was to be ordy put in service on oil or coal.

Revised text allows greater flexibility as to when the leak test is to be performed.

It mandates a fuel gas header leak test only prior to putting the fuel gas system in service and not as a general boiler purge requirement when possibly an alternate fuel will be put in service, COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #95) 8502- 21 - (6-5.2.1.3(e)): Reject SUBMITTER: S. Dharmalingam, Bharat Heavy Electricals Ltd. RECOMMENDATION: Add the end of Section 6-5.2.1.3(e), the following new Clause may be adde&

"Facility shall be provided for manual interruption of unit Dur~n~.u "n ." ~UI~STANTIATION: Provision of "Purge Stop ~ push button enhances the flexibility to the operator. The unit purge time varies between 5 to' 10 rain depending upon the boiler volume. In the existing arrangement, if the operator wants to stop purging due to any reasons, it is not possible and they have to wait unit "P-urge Completion". COMMITTEE ACTION: Reject. COMMITrEE STATEMENT: The recommendation is not safety related and is not prohibited by the standard. This is a design

eCific issue. BER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25

VOTE ON COMMI'I'rEE ACTION: AFFIRMATIVE: 25

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(Log #96) 8502- 22 - (6-5.2.1.5(g)): Reject SUBMITTER: S. Dharmaiingam, Bharat Heavy Electrlcals Ltd. RECOMMENDATION: Add the end of Section 6-5.2.1.3(g), the following new Clause may be added:

"The main safety shut offvalve shall be closed automatically, if the shut off valve is open for more than 5 min and gas firing is not started." SUBSTANTIATION: Presently number of by-product gases, which are inflammable and toxic are fired in boilers. Though header leak test is carried out before unit purge, charging of gas lines for more time, without actual firing, may lead to leakage of toxic gases, resulting in a dangerous condition. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The issue raised by the submitter is addressed by the caution statement following Section 6-5.2.1.5(g). The actual vent time is a function of unit design. The firing of byproduct gases is not covered by this standard. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #42) 8502- 25 - (6-5.2.1.~,(o)): Accept SUBMITTER: Bernard Hrul, Allen-Bradley Co. Inc. RECOMMENDATION: Change reference in 6-5.2.1.3(o) from 6-5.2.1.3(c) to 6-5.4.6. SUBSTANTIATION: References need to be updated. The Technical Committee agreed to move the leak test text to a new section. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #28) 8502- 26- (6-5.2.3.5): Accept SUBMITTER: Dale E. Dressel, Monsanto Co. RECOMMENDATION: Revise Section 6-5.2.5.5 as follows:

6-5.2.5.5 As the fuel is reduced, a sequential shutdown of the burners shall be accomplished by closing the individual burner safety shutoff valves and opening the vent valves. Registers shall be

~ laced in the proper position. UBSTANTIATION: The previous wording required following

"the reverse procedure of that used during start-up for normal shutdown". This is not very clear and could be interpreted to mean that starting the igniter system is required. For gas, this is not intended to be required, because the igniter is not required to be placed in service in order to remove the gas burner(s). COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #44) 8502- 27 - (6-5.2.3.3): Accept in Principle SUBMITTER: Laiit M. Mehta, Coen Co., Inc~ RECOMMENDATION: Revise text as follows:

6-5.2.5.3 When the last individual burner safety shutoffvalves are closed, the main safety shutoff valve shall be closed. SUBSTANTIATION: This revised Section darifies the intent of the Committee and reflects current industry practices. COMMITFEE ACTION: Accept in Principle.

I Change the Section number of the proposed recommendation to I Section 6-5.2.3.4 with no other changes.

COMMITTEE STATEMENT: The change is made only to correct the section number from 6-5.2.5.5 to 6-5.2.5.4. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #57) 8502- 24 - (6-5.2.2.4(a), (b), and (c) (New)): Accept SUBMITTER: Francisco A. Palacios, D B Riley, Inc. RECOMMENDATION: Add tlae word "gas" to sentences 6-5.2.2.4(a) and 6-5.2.2.4(b) and add sentence (c) under Section 6-5.2.2.4. Changes will read:

(a) With all g ~ burners in service and combustion controls on automatic,

(b) With different combination of g ~ burners in service and combustion controls on automatic, and

(c) With different combinations of Eras. oil and coal burners in service and combustion controls on automatic. SUBSTANTIATION: Normal operation of firing natural gas (Section 6-5.2.2) appears to apply for both single and dual fuel. The only appropriate change is to add a requirement in 6-5.2.2.4 stating that trial test should be done for dual fuel firing. Adding the word "gas" to the existing text is for clarity. COMMITTEE ACTION: Accept. NUMBER OF COMMrlq'EE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #21) 8502- 25 - (6-5.2.3): Accept SUBMITTER~ RaymondJ. Heidand, Monsanto Co.

I RECOMMENDATION: Revise Section 6-5.2.3 as follows: I 6-5.2.3 Normal Shutdown. This section covers the requirements I for removing gas from service as the only fuel being fired. Section ] 6-5.2.7 covers the requirements for removing gas from service with I other fuel remaining in service.

SUBSTANTIATION: This addition clarifies the difference between multiple and single fuel operation and directs the reader to the appropriate section. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Cog #1) 8502- 28 - (6-5.2.5.2(b), 7-5.2.5.2(b), 8-5.2.5.2(b)): Reject Note: This Proposal appeared as Comment 85C-16 which was

held from file Annual 95 ROC on Proposal N/A. SUBMITTER: Robert W. Hill, Amtech Services RECOMMENDATION: The subject sections should read as follows:

(b) Whenever the total airflow drops below 20 percent of full load volumetric airflow. SUBSTANTIATION: The "purge rate" by definition can be any rate above 25 percent for gas or oil, or any rate between 25 and 40 percent for coal. The present wording ties the MFr trip point to 5 percent below tile selected purge rate. Thus for a boiler purging at 50 percent, the MFT would be set for 45 percent, much too high.

MFT trip point is a function of a dangerously low airflow. Purge rate may be selected much higher based on a time consideration. The two are unrelated except for the minimum requirement.

I suggest a trip point of 20 percent, because this is the minimum allowed now, i.e., 5 percent below 25 percent. The committee may prefer 25 percent.

Combustion control systems today usually provide a minimum air flow demand. This should be covered under 4-5.2 as follows:

"The controls system design shall provide means to limit the demand for air flow to 5 percent above the MFI" trip point." COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The intent of the Committee is to trip at 5 percent below the flow rate the unit is purged at. If the unit is cleared at a higher air flow (40percent maximum for coal fired units) then the air flow can be reduced to the purge rate for the last 5 minutes. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #13) 8502- 29 - (6-5.2.5.3 and 6-5.2.5.4): Accept in Principle SUBMITTER= Bill Bass, Forney Corp. RECOMMENDATION: Change "post-firing unit purge" to "unit purge". SUBSTANTIATION: Some system designers (and some end users) believe there is a difference between a "post-firing unit

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purge" and a normal "unit purge". As a result, those systems require the operator to perform a 5 minute "post-firing unit purge" followed by a 5 minute "unit purge r for a total of ten dainute-s of- purging after a master fuel trip. I do not believe that is the intent of the standard. COMMITTEE ACTION: Accept in Principle.

In Section 6-5.2.5.3, in the third sentence change the term "post- firing" to "unit" and in the last sentence delete the term "post- firing".

Text will now read as follows: "ff the airflow is above the purge rate, it shall be permitted to be

decreased gradually to the purge rate for a pc.~t.'L'~ng unit purge. If the airflow is below the purge rate at the time of the trip, it shall be continued at the existing rate fro 5 minutes and then increased gradually to the purge rate airflow and held at this value for a ~ : : fi~ng unit purge."

In Section 6-5.2.5.4, in the last sentence delete the term "post- firing".

Text will now read as follows: "The airflow shall be increased gradually to the purge rate and a

post-firing- unit purge shall be completed." COIVIMITTEE STATEMENT: Additional changes are required to meet the intent of the submitter. Committee intent is to require a purge of not less than 5 minutes, or five changes in volume of the boiler enclosure, whichever is Iong~er. This is the definition of "Unit Purge". NUMBER OF COMMITTEE MEIVIBERS ELIGIBLE TO VOTE: 25 VOTE ON COlVlMITTEE ACTION:

AFFIRMATIVE: 25

(Log #CP3) 8502-29a- (6-5.2.5.5(b), 7-5.2.5.6(b), 8-5.2.5.5(b)): Accept SUBMITTER= Technical Committee on Multiple Burner Boilers RECOMMENDATION: Revise the first sentence of Sections 6-5.2.5.5(b), 7-5.2.5.6(b) and 8-5.2.5.5(b) as follows:

"ff a unit purge was successfully completed following an emergency shutdown and the conditions..." SUBSTANTIATION: The revised wording clarifies the intent of the Committee. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #22) 8502- 30 - (6-5.2.6 (New)): Accept SUBMITTER: Blair Kerstetter, The Foxboro Co. RECOMMENDATION: Add new text as follows:

6-5.2.6 Starting Sequence Second Fuel. 6-5.2.6.1 When starting gas as a second fuel, the requirements of

6-5.2.1.1(h) through 6-5.2.1.1(m) shall have been satisfied, see 6-5.4.8.

6-5.2.6.2 The starting sequence of the first fuel (oil or coal) shall be complete. The starting sequence of second fuel (gas) shall be performed in the following order (See Section 6-5.4.6-for leak test requirements):

(a) ~ The main gas control valve shall be closed and the main safety shutoff valve(s) shall be opened.

(b) The starting sequence in Sections 6-5.2.1.3(0 through 6-5.2.1.3(j) shall be followed.

(c) After making{ certain that the ignitor(s) is established and is providing appropriate ignition energy for the main burner(s), the individual burner safety shutoff valve(s) shall be opened and the individual burner atmospheric vent valves shall be closed. Failure to ignite or loss of ignition for any reason on any burner(s) shall cause fuel flow to that burner(s) to stop. All conditions for proper light-off shall exist before restarting the burner(s).

(d) The starting sequence in Sections 6-5.2.1.3(1) through 6- 5.2.1.3(s) shall be followed. SUBSTANTIATION: Section 6-5.2.1 describes the cold start sequence of natural gas as the first fuel fired. While portions of the cold sequence applies to the second fuel start sequence, a new Section (6-5.2.6) dried "Starting Sequence Second Fuel" is recommended for clarity. COMMITTEE ACTION: Accept.

I The following editorial change is needed: Change the spelling of "ignitor" to "igniter" in Section 6-5.2.6.2(c).

(c) After making certain that the igniter(s) is established and is Pnroviding appropriate ignition energy for the main burner(s), the

dividual burner safety shutoffvalve(s) shall be opened and the individual burner atmospheric vent valves shall be dosed. Failure to ignite or loss of ignition for any reason on any burner(s) shall causse fuel flow to that burner(s) to stop. All conditions for proper light-off shall exist before restarting the burner(s). NUMBER OF COMMITTEE MFAIBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #16) 8502- 31 - (6-5.2.7 (New)): Accept SUBMITTER: Daniel Lee, Bailey Controls Co. RECOMMENDATION: Add new text as follows:

6-5.2.7 Shutdown Sequence Second Fuel. This section covers the requirements for removing gas from service with other fuel remaining in service. Section 6-5.2.3 covers the requirements for removing gas from service as the only fuel being fired.

6-5.2.7.1 When shutting off gas with oil or coal remaining in service, a sequential shutdown of the gas burners shall be accomplished by closing the individual burner safety shutoffvalves and opening the vent valves. .

6-5.2.7.2 Shut down the remaining burners sequentially as previously described leaving the regn'sters in the proper position.

6-5.2.7.3 When the last individual burner safety shutoff valves are closed, the main safet~ shutoff valve shall be closed.

6-5.2.7.4 All atmospheric vent valves shall be opened to minimize the possibility of gas leaking into the boiler endosure. SUBSTANTIATION: Seclffon 6-5.2.3 describes the normal shutdown of natural gas when firing as a single fuel. While portions of the normal shutdown sequence applies to the second fuel's shutdown, a new Section (6-5.2.7) t ided"Shutdown Sequence Second Fuel" is recommended for clarity. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #CP1) 8502- 31a- (6-5.4.2, 7-5.4.2, 8-5.5.2): Accept SUBMITFER= Technical Committee on Multiple Burner Boilers RECOMMENDATION: Revise the text of Sections 6-5.4.2, 7-5.4.2 and 8-5.5.2 to read as follows:

"A unit purge shall be completed prior to starting a fire in the furnace." SUBSTANTIATION: Committee intent is to require a purge of not less than 5 minutes, or five changes in volume of the boiler enclosure, whichever is longer. This is the definition of "Unit Purge". COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #CP4) 8502- 31b - (6-5.4.5, %5.4.6, 8-5.5.5): Accept SUBMITrER: Technical Committee on Multiple Burner Boilers

I RECOMMENDATION: In the last sentence of Sections 6-5.4.5, 7-5.4.6 and 8-5.5.5, add the word "rate" between the words "purge r and "airflow" to read "purge rate airflow". SUBSTANTIATION: The revised wording clarifies the intent of the committee. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

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N F P A 8 5 0 2 1 F 9 8 R O P

(Log #5) 8502- 32 - (6-5.4.8): Accept SUBMITTER: Bill Bass, Forney Corp. RECOMMENDATION: Add Section 6-5.4.8 to read:

6-5.4.8 The total heat input within a burner or furnace zone, or both, shall not exceed the maximum limits specified for the equipment. Special consideration shall be gwen where a burner or furnace zone, or both, simultaneously fires more than one fuel. SUBSTANTIATION: Since NFPA 8502 covers multiple fuel firing, burner heat input limi~ are an operating requirement when considering fuel transfer or dual fuel firing. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #59) 8502- 34 - (6-6.3.1.1(b)): Reject SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Add after the last sentence:

"A master fuel trip shall be actuated if the igniters are Class I and no other fuel is in service." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: This material is adequately addressed in the new diagram covered by Proposal 8502-33 (Log #56). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

11c.

8502- 33 - (Figure 6-6.3.1.1): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise figure as shown below:

~ fUel t r i p ~ tys t~ fn ' I LOSS o f ign i te r f l a m e I 2. I Ign i te r fue l p r e s s u r e OUt o f s tab le r a n g e

(Log #56)

3. LOSS o f ID t an (s )

4. L o s s o f FD fan (s )

/~. C o m b u s t i o n a i r flOW IOW

8. EXCESS f u r n a c e p r e s s u r e

7. L o s s o f al l f l an l~

8. Par l l a l l oss of f l a m e I n t r oduc i ng h a z a r d

9. Al l fue l i npu ts z e r o

10. M a n u a l t r ip Swi tch

cp L

9 :;:

11a. Od fUel t r ip ( s e e F I Q U r B 7 - 6 . 3 . 1 . 1 ) I

11b,

12Q. I 12b. [

. I ~,°'r. '~°' ,"o°;~.".¢~'I r I I a n d d e e n e r g i z e sparRs I I tOni tar tue f t ip f o r C t l l s 1 |

1 ign i te rs , b lOck 11c I

~ f e t y shu to f f v a l v e s ~ l ¢k)energ~ze ~p~rk~

I o--oO.Too o,._,o.. . . . .

C o ~ I fUel t r ip ( s e e F~gur~ 8-6 .3 . I . 7) I I ~ u l o f f va lVe(S) ancl I i nd i v i dua l ~ U f ~ r Ign i te r fue l t r lp ( C l a s s 1 Ign i le rs ) I ~ l t e t y shu to f f v a l v e d

B u r n e r g a s h e a d e r fue l p r e s s u r e l ow I ~ ) s e e I : l o u r B s - 7 - ~ . 3 . ~. ! m n c l I [ . . . . . . . )

I I . . . . . ,,oo, o . . . . . . . . . , . . . . . . . I I 9 1 ~. on~) or m o r e edC~ttonal S lab le b u r n e r f la~r les p r e s e n t

" - i . . . . . . . . . dua l I~J . . . . . . . t Y i h . . . . . . . y.e(s) I a n d Inc~l~ddual Ign i te r ~ t e t y shu to f f v~ l v~ ( s ) a n d d e e n e r o I z o a s s o c i a t e d s p a r k i

F u r n a c e p u r g e s y l t e r n

[ I l g h . . . . . . . . . . . . . . H A r e a l g a . H I I . . . . . . . . . . . f i red, H I . . . . . . . . . . . . . I a n d i nd i v i dua l i gn i te r h e ~ d e r e n d e r ~ all m a i n ol l a r e ~1| p u l v e r l z e m i nd i v i dua l a s b u r n e r h ~ d e r a n d ind iv idu~ l trt ~d. ~11 ¢x~ l llo~v s a f e t y shu to f f valV~I!IS ~ t e t y thUC~Oaff tolt~uumece s topped , od b u r n e r = t e t y P-~tof, e d ? v a l v e s clow.~Dd? shu to f f v a l v e s c lo l te¢ l? a n d el l s a f e t y shu to f f

• v a l v e s c l o u d ?

r ~ i s t e r s o p e n ? FD f a n s r u n n i n g ? a t p u r g e ra te? d e l a y t r ip re l ay (s )

Figure 6-6.3.1.1 Interlock system for natural gas-f'wed multiple burner boiler.

SUBSTANTIATION: Revised to address multiple fuel firing in the boiler. COMMITTEE ACTION: Accept.

The following editorial changes are needed: Throughout the figure, change the term "ignitor" to ~igniter". In the second block in the upper fight hand corner change the

term "tip" to "trip". NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #60) 8502- 35 - (6-6.3.1.1(d)): Accept SUBMITI?ER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"(d) Blocks 3 through 12 represent conditions... (in the sixth line) Whenever the master fuel trip." SUBSTANTIATION: Revise to address multiple fuel firing in the belier per Figure 6-6.3.1.I. COMMITTEE ACTION: Accept.

The following editorial changes are needed: The period after file term "master fuel trip" is not part of the

proposed change and should be removed. The term "(in the sixth line)" is not part of the proposal wording.

It is a direction to editorial staff. Text will now read as follows:

122

N F P A 8 5 0 2 - - F9 8 R O P

(d) Blocks 3 through 12 represent conditions that initiate the tripping of both the main and ignition fuel supply through a master fuel trip relay. The master fuel trip relay shall be of the type that stays tripped until the furnace purge system allows it to be reset, as shown at the bottom of Figure 6-6.3.1.1. Whenever the master fuel trip relay is operated, it trips all safety shutoff valves and deenergizes sparks. T h e interlocks are as follows: NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #61) 8502- 36 - (6-6.3.1.1 (d) 1): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 3 and 4 represent conditions... (in the fourth line make a note that starts with) The loss of one induced." SUBSTANTIATION: The control and tripping philosophy of individual induced and forced fan is design specific. COMMITTEE ACTION: Accept in Principle.

I Revise the text of 6-6.B.l.l(d)l to read as follows: [ Blocks 3 and 4 represent protection against loss of large [ quantities of combustion air. The loss of all induced draft fans or [ all forced draft fans shall operate the master fuel trip relay.

COMMITTEE STATEMENT: The text deleted by the Committee Action is included in Section 4-5. Refer to Proposal 8502-15 (Log #51). This meets the intent of the submitter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #62) 8502- 37 - (6-6.3.1.1 (d)2): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 5 represent low..." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITTEE ACTION: Accept.

I he following editorial correction is needed: The revised text should read: "Block 5 represents low combustion airflow below the permitted

limits and is interlocked to activate the master fuel trip relay." NUMBER OF COMMITFEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #63) 8502- 38- (6-6.3.1.1(d)5): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Excess furnacepressure (Block 6) also...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #64) 8502- 39 - (6-6.3.1.1(d)4): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

~Nhen the main burner header fuel pressure (Blocks 12a and 12b) is above the maximum or below the minimum for stable flame, that fuel shall be tripped. If it is the only fuel in service (blocks l l a , l l b , and 11c) the master fuel trip relay shall be actuated. See Table 6-5.2.5.2(a), items (a) and (h)." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITTEE ACTION: Accept in Principle.

Revise the submitter's proposal to read as follows: "When the gas burner header fuel pressure (Blocks 12a and 12b)

is above the maximum or below the minimum for stable flame, that fuel shall be tripped. If gas was the only fuel in service

I (Blocks l l a , l l b , and l l c ) the master fuel trip relay shall be actuated. See Table 6-5.2.5.2(a), items (a) and (h)." COMMITTEE STATEMENT: Editorially revised to clarify meanin . NUMBi~R OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25 COMMENT ON AFFIRMATIVE:

MILONE: In both the original Proposal and Committee Action the last sentence in this paragraph refers to Table 6-5.2.5.2(a), items (a) and (h). This table has not been revised to incorporate the gas fuel trip. Two separate tables should be provided, one entitled Mandatory Automatic Fuel Gas Trips and the other entitled Automatic Master Fuel Trips. Also, existing Table 6- 5.2.5.2(b) should be renumbered as 6-5.2.5.2(c).

Table 6-5.2.5.2(a) should read: gas fuel trip shall result from any of the following conditions:

A ( a ) Fuel pressure at the burner below... (b) High fuel gas pressure. (c) Last individual burner safety shutoff valve closed.

MFT Table 6-5.2.5.2(b) should be the same as the existing section with the following exception:

1. Replace the text in (a) with "All fuel trip relays (including Class I ignitor trip) activated"

2. Omit (g) a n d ( h ) .

(Log #65) 8502- 40 - (6-6.3.1.1(d)5): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 7 represents loss of...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITTEE ACTION: Accept.

] Editorially delete the %" in the word "blocks". ] The revised text should read: I "Block 7 represents loss of all flame in the furnace and is ] interlocked to activate the master fuel trip relay."

NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25


"Blocks 8 represents a partial loss of...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITI'EE ACTION: Accept.

I Editorially delete the %" in the word "blocks'. The revised text should read: "Block 8 represents a partial loss of flame to the extent that

hazardous conditions could develop irrespective of, or due to the failure of, other protective interlocks." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #67) 8502- 42 - (6-6.3.1.1 (d)7): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 9 represents an interlock...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITTEE ACTION: Accept.

Editorially delete the %" in the word "blocks". The revised text should read: "Block 9 represents an interlock operation when all fuel inputs to

the furnace are shut off following a shutdown of the boiler for any reason." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

123

N F P A 8 5 0 2 - - F9 8 R O P

(Log #68) 8502- 43 - (6-6.3.1.1 (d)8): Accej)t SUBM1TTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 10 represents a manual...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6-6.3.1.1. COMMITTEE ACTION: Accept.

[ Editorially delete the "s" in the word "blocks". The revised text should read:

[ "Block 10 represents a manual switch that can be used by the operator in an emergency to actuate the master fuel trip relay." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #69) 8502- 44- (6-6.3.1.1(e)): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 1,3 represents loss of flame... (in the fifth line) 6- 6.3.1.1(d)6 (B/ock 8). This trip...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 6.6.3.1.1. COMMITTEE ACTION: Accept in Principle.

Revise Section 6-6.3.1.1 (e) as follows: In the first line change "Block 15" to "Block 13". In the fifth line change "Block 12" to "Block 8".

COMMITTEE STATEMENT: The revised text meets the intent of the submitter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #GP6) 8502- 44a- (6.6.3.1.3): Accept SUBMITTER: Technical Committee on Multiple Burner Boilers RECOMMENDATION: Revise the third sentence of Section 6- 6.3.1.3 as follows:

"...position and all burner header, igniter header, individual burner and individual igniter safety shutoff valves are proven closed before..."

Add an Exception following Section 6-6.3.1.3 to read as follows: Exception: Where the igniter capacity is five million BTU/hr or

less, indirect monitoring of the valve position shall be permitted to be used to establish that these valves are proven closed. SUBSTANTIATION: The revision is made to be consistent with Committee Action taken on Proposal 8502-57. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITrEE ACTION:


EXPLANATION OF NEGATIVE: WILLSE: We are adding an Exception to the sections dealing

with igniters. In it we are stating they can use "indirect monitoring" yet we do not explain what "indirect monitoring" is. In addition, in the last sentence of the Committee Statement it states "In this case, the authority having jurisdiction should be satisfied that reasonable supervision is provided. If we indeed mean the authority having jurisdiction needs to be satisfied, then we must first state "Where acceptable to the authority having jurisdiction, igniters with a capacity of five million BTU/hr or less shall be permitted to have indirect monltorin~ of the valve position." And indicate what is indirect momtoring.

NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

25

(Log #9) 8502- 45 - (6-8.2.1 through 6-8.2.9): Accept in Principle SUBMITrER: Bill Bass, Forney Corp. RECOMMENDATION: Change reference to figures from [See figures A-6.5.1.2(a) and (b).] to [See figures A-8-5.1.1(a) and (b).] SUBSTANTIATION: Text references wrong figures. COMMITTEE ACTION: Accept in Principle.

I evise the submitter's proposal to read as follows: Change reference to figures from [See Figures A-6-5.1.2(a) and

(b).] to [See Figures A-6.8.1.1(a) and (b).] COMMITTEE STATEMENT: The revised text is an correction. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #CPg) 8502- 45a- (6-8.2.9(b)3 and 6-8.2.9(b)4): Accept SUBMITrER: Technical Committee on Multiple Burner Boilers RECOMMENDATION: In Section 6-8.2.9(b)3 delete the term "post-firing". Text will now read as follows:

3. If the airflow is above purge rate, it shall be permitted to he decreased gradually to this value and a pc~t firing unit purge shall be performed.

In Section 6.8.2.9(b)4 delete the term "post-firing". Text will now read as follows:

4. If the airflow is below purge rate at the time of the trip, it shall be continued at the existing rate for 5 minutes and then increased gradually to purge rate and held at this value for a ~c:t .~r'::=g unit

[~ urge. . UI~TANTIATION: Committee intent is to reqmre a purge ot

not less than 5 minutes, or five changes in volume of the boiler enclosure, whichever is longer. This is the definition of "Unit Purge".

Also see Committee Action and Committee Statement on Proposal 8502-29 (Log #13). COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #2) 8502- 46 - (6-9.1.2): Reject SUBMITTER: Lalit M. Mehta, Coen Co., Inc. RECOMMENDATION: Revise text as follows:

Add to the end of the sentence, "(See NFPA 8501, Standard for Single Burner Boiler Operation)."

Designer shall take in-consideration boiler common interlocks for boiler MFF, and boiler purge. SUBSTANTIATION: It is not clear (as is in 6-9.1.3) that NFPA 8501 applies. Sections 6-9.1.2 and 6-9.1.5 text will then match. MF'r should be to both burners and designer should address that part of the interlock and boiler purge interlock. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: NFPA 8501 does not apply to this raph

BER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #CP5) 8502- 44b - (6-8.1.3(a)): Accept SUBMITTER: Technical Committee on Multiple Burner Boilers RECOMMEN. DATION: Revise Sections 6-8.1.3(a) and 7-8.1.3(a) to read as follows:

(a) The airflow shall be adjusted to the purge rate and a unit purge shall beperformed. SUBSTANTIATION: The existing text does not convey the intent of the committee. COMMITTEE ACTION: Accept.

(Log #35) 8502- 47 - (7-5.2.1): Accept SUBMITTER= George Y. Keller, Burns & Roe

[ RECOMMENDATION: Revise Section 7-5.2.1 to read as follows: %5.2.1 Gold Start. This section covers the requirements for

[ placing oil in service as the initial fuel being fired. Section 7-5.2.6 covers the requirements for placing oil in service as a subsequent

| fuel. SUBSTANTIATION: This addition clarifies the difference between first and subsequent fuels. COMMITTEE ACTION: Accept.

124

N F P A 8 5 0 2 - - F 9 8 R O P


AFFIRMATWE: 25

(Log #26) 8502- 48 - (7-5.2.1.1): Accept SUBMITTER: J o h n P. O'Rourke, ABB Combust ion Engineering, Inc. RECOMMENDATION: In Section 7-5.2.1.1, replace existing subsections (f) th rough (n) with the following:

"(f) The proper d rum water level is established in drum-type boilers, and circulating flow is established in forced circulation boilers, or min imum water flow is established in once-through boilers.

(g) The oxygen analyzers and combustibles analyzers, if provided, are operat ing satisfactorily and a sample has been obtained. Combustibles indication is at zero and oxygen indication is at maximum.

(h) All safety shutoff valves are closed. All sparks are deenergized.

(i) For gas ignition systems, see Chapter 6. I i l l i o (J)n Thethe burnerCirculatingheaders.Valves are open to provide and maintain hot

(k) The burner guns are checked for proper tips or" sprayer plates. [See Section 7-2(f)]

(1) The burner elements and igniters are posit ioned in accordance with the manufacturer 's specification.

(m) Energy is supplied to control system and to safety interlocks. (n) The meters or gauges indicate fuel header pressure to the

unit." SUBSTANTIATION: Sections were r enumbered to organize items for multiple fuel firing startup sequences. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #38) 8502- 49 - (7-5.2.2.4(a), (b), and (c) (New)): Accept SUBMITTER: Francisco A. Palacios, D B Riley, Inc. RECOMMENDATION: Add the word "oil" to sentences (a) and (b) and add sentence (c) unde r Section 7-5.2.2.4. Changes will read:

(a) With all oil burners in service and combustion controls on automatic,

(b) With different combinations ofo i l burners in service and combust ion controls on automatic, and

(c) With different combinations of gas. oil. and coal burners in service and combustion controls on automatic, SUBSTANTIATION: Normal operation of firing oil (Section 7- 5.2.2) appears to apply for both single and dual fuel. The only appropriate change is to add a requi rement in 7-5.2.2.4 stating that trial tests should be done for dual fuel firing. Adding file word "oil" to the exis t ingtext is for clarity. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATWE: 25

(Log #20) 8502- 50- (7-5.2.3): Accept SUBMITTER: RaymondJ . Heit land, Monsanto Co.

I RECOMMENDATION: Revise Section 7-5.2.3 as follows: 7-5.2.3 Normal Shutdown. This section covers the requirements

for removing oil f rom service as the only fuel being fired. Section 7-5.2.7 covers the requirements for removing oil f rom service with o ther fuel remaining in service. SUBSTANTIATION: This addit ion clarifies the difference between multiple and single fuel operation and directs the reader to the appropriate section. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #29) 8502- 51 - (7-5.2.3.3): Accept SUBMITrER: Dale E. Dressel, Monsanto Co. RECOMMENDATION: Revise Section 7-5.2.3.3 to read as follows:

7-5.2.3.3 As the fuel is reduced, a sequential shutdown of the burners shall be accomplished by closing the individual burner safety shutoff valves. Each burner shall be shut down in the following sequence:

(a) The igniter shall be placed into service on the particular burner to be shut dowrl.

(b) With the igniter in service, the burner safety shutoff valve shall be closed and the steam (or air) clearing valves shall be opened.

(c) The clearing steam (or clearing air) shall be left in service a sufficient length of time to remove all oil that could carbonize and plug the burner tip.

(d) The igniter shall be removed from service, and the oil gun shall be removed or retracted unless cooling is provided.

(e) If the oil passages of the igniter are to be cleared into the furnace, the spark or other ignition source for the igniter shall be initiated before opening the steam (or air) clearing valve.

(f) Registers shall be placed in the proper position. SUBSTANTIATION: The previous wording required following "the reverse of the start-up procedures". This is not very clear and could be misinterpreted. The revised wording more clearly states the intentions of the committee. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #43) 8502- 52 - (7-5.2.3.4): Accept SUBMITTER: Lalit M. Mehta, Coen Co., Inc.

I RECOMMENDATION: Revise text as follows: 7-5.2.3.4 As the fuel is reduced, the remaining burners shall be

shutdown sequentially as descr ibed in 7-5.2.$.3. The last burner shall no t be scavenged.

Exception: Where associated Class 1 igniters are in use, the last burner shall be permi t ted to be scavenged. SUBSTANTIATION: This revised section clarifies the i n t en t of the committee and reflects cur ren t Industry practices. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #14) 8502- 53 - (7-5.2.5.4 and 7-5.2.5.5 ): Accept in Principle SUBMITTER: Bill Bass, Forney Corp. RECOMMENDATION: Change "post-firing unit purge" to "unit

~ urge". U~STANTIATION: Some system designers ( and some end

users) believe there is a difference between a "post-firing unit purge" and a normal "unit purge ' . As a result, those systems require the operator to perform a 5 minute "post-firing unit purge" followed by a 5 minute "unit purge" for a total of ten minutes of purging after a master fuel trip. I do no t believe that is the intent of the standard. COMMITTEE ACTION: Accept in Principle.

In Section 7-5.2.5.4, in the third sentence change the term "post- firing" m "unit" and in the last sentence delete the term "post- firing".

Text will now read as follows: ~ff the airflow is above the purge rate, it shall be permit ted to be

decreased gradually to the purge rate for a pe~t .q='~g unit purge. If the airflow is below the purge rate at the time of the trip, it shall be cont inued at the existing rate for 5 minutes and then increased ~radually. to the purge rate airflow and held at this value for a ~ .z t £.~.ng umt purge."

In Section 7-5.2.5.5, in the last sentence delete the term "post- firing".

Text will now read as follows: "The airflow shall be increased gradually to tbe purge rate and a

nit purge shall be completed." STATEMENT: Additional changes are required to

meet the intent of the suhmitter. Commit tee intent is to require a purge of not less than 5 minutes, or five changes in volume of the

125

N F P A 8502 - - F98 R O P

boiler enclosure, whichever is longer. This is the definition of "Unit Purge". NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #23) 8502- 54 - (7-5.2.6 (New)): Accept SUBMITTER: Blair Kerstetter, The Foxboro Co. RECOMMENDATION: Add new text as follows:

7-5.2.6 Starting Sequence Second Fuel. %5.2.6.1 When starting oil as a second fuel, the requirements of

7-5.2.1.I(b) through 7-5.2.1.1(n) shall be satisfied, see 7-5.4.8. 7-5.2.6.2 The starting sequence of the first fuel (gas or coal) shall

be complete. The starting sequence of second fuel (oil) shall be performed in the following order:

(a) The main oil control valve shall be closed and the main safety shutoffvalve(s) shall be opened. (See Section 7-5.4.6 for leak test requirements).

(b) The starting sequence in 7-5.2.1.3(g) through (t) shall be followed. SUBSTANTIATION: Section 7-5.2.1 describes the cold start sequence of fuel oil as the first fuel fired. While portions of the cold sequence applies to the second fuel start sequence, a new Section (7-5.2.6) titled "Starting Sequence Second Fuel" is recommended for clarity. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25


7-5.2.7 Shutdown Sequence Second Fuel. This section covers the requirements for removing oil from service with other fuel remaining in service. Section 7-5.2.$ covers the requirements for removing oil from service as the only fuel being fired.

7-5.2.7.1 When shutting off oil with gas or coal remaining.in service, a sequential shutdown of the oil burners shall be accomplished by the following sequence:

(a) Place the ignitor into service on the particular burner to be shut down.

(b) With the ignitor in service the burner safety shutoff valve shall be closed and the steam (or air) clearing valves shall be opened.

(c) The clearing steam (or air) shall be left in service a sufficient length of time to remove all oil that could carbonize and plug the burner tip.

(d) The ignitor shall be removed from service and the oil gun shall be removed or retracted unless cooling is provided.

7-5.2.7.2 Shutdown the remaining burners sequentially as previously described leaving the registers in the proper position.

7-5.2.7.3 When the last individual burner safety shutoff" valve is closed, the main safety shutoff valve shall be closed. SUBSTANTIATION: Section 7-5.2.3 describes the normal shutdown of oll when firing as a single fuel. Whileport ions of the normal shutdown sequence a~j~lies to the second fuel's shutdown, a new Section (7-5.2.7) titled Slmtdown Sequence Second Fuel" is recommended for clarity. COMMITTEE ACTION: Accept.

J Editorially change the term "igniter" to "igniter throughout the I recommended text to read as follows: ] 7-5.2.7 Shutdown Sequence Second Fuel. This section covers the [ requirements for removing oil from service with other fuel I remaining in service. Section 7-5.2.~, covers the requirements for J removing oil from service as the only fuel being fired. [ %5.2.7.1 When shutting off oil with gas or coal remaining in J service, a sequential shutdown of the oil burners shall be accompl ished by the following sequence: i (a) Place the igniter into service on the particular burner to be shut down.

(b) With the igniter in service the burner safety shutoff valve shall ! be closed and the steam (or air) clearing valves shall be opened.

(c) The clearing steam (or air) shall be left in service a sufficient length of time to remove all oil that could carbonize and plug the burner tip.

(d) The igniter shall be removed from service and the oil gun shall be removed or retracted unless cooling is provided.

I 7-5.2.7.2 Shutdown the remaining burners sequentially as previously described leaving the registers in the proper position.

7-5.2.7.3 When the last individual burner safety sbutoffvalve is closed, the main safety shutoff" valve shall be closed. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #fi) 8502- 56 - (7-5.4.8): Accept SUBMITTER: Bill Bass, Forney Corp.

[ RECOMMENDATION: Add Section 7-5.4.8 to read: I 7-5.4.8 The total heat input within a burner or furnace zone, or I both, shall not exceed the maximum limits specified for the I equipment. Special consideration shall be given where a burner [ or furnace zone, or both, simultaneously fires more than one fuel.

SUBSTANTIATION: Since NFPA 8502 covers multiple fuel firing, burner heat input limits are an operating requirement when considering fuel transfer or dual fuel firing. COMMITTEE ACTION: Accept. NUMBER OF COMMITI3gE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #53) 8502- 57 - (Figure 7-6.3.1.1): Accept in Prindple SUBM/TTER: Joan Kraiza, ABB Combustion Engr Inc. RECOMMENDATION: Change Figure 7-6.3.1.1 in the block below "Furnace Purge System" to read:

"Are all main, igniter header, and individual burner safety shutoff" valvesproven closed?" SUBSTANTIATION: Text and illustrations do not agree Or are ambiguous. The necessity of proving the individual igniter safety shutoffvalves closed for purge has never been established. By revising the block diagram, both text and figures agree. COMMITTEE ACTION: Accept in Principle.

J Revise the third sentence of Section 7-6.3.1.4 as follows: [ "...position and all burner header, igniter header, individual J burner and individual igniter safety shutoff" valves are proven closed I before..." J Add an Exception following Section 7-6.3.1.4 to read as follows: J Exception: Where the igniter capacity is five million BTU/hr or ] less, indirect moni to r ingof the valve position shall be permitted I to be used to establish that these valves are proven dosed.

COMMITTEE STATEMENT: The submitter 's proposal eliminates the requirement to provide supervision of all individual igniter safety shutoff during a unit purge regardless of igniter capacity. Supervision of individual igniter safety shutoff valves is required during a unit purge where the igniter capacity is sufficient to create a hazardous condition in the event that a individual igniter safety shutoff valve is open during a unit purge. In this case, the authority baying jurlsdiction should be satisfied that reasonable supervision is provided. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: WILLSE: See my Explanation of Negative on Proposal 8502-44a

• (Log #CPt).

(Log #57) 8502- 58- (Figure 7-6.3.1.1): Accept SUBMI'I'FER: W. Scott Matz, Triconex Systems Inc.

[ RECOMMENDATION: Revise figure as shown on page 127: SUBSTANTIATION: Revised to address multiple fuel firing in the boiler. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: The following editorial changes are needed:

Throughout the figure, change the term "ignitor" to "igniter". In the second block in the upper right hand corner change the

term "tip" to "trip". NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITI'EE ACTION:

AFFIRMATIVE: 25

126

N F P A 8 5 0 2 1 F 9 8 R O P

O U f u e l t r i p s y s t e m

I . I L o s s o f i g n i t e r f l a m e I

2 a . I I g n i t e r f u e l p r e s s u r e out o f s ~ b l e r a n g e

2 b . [ I g n i t e r a t o m i z i n g m e d i u m p r e s s u r e i m p r o p e r

L o s s o f I D f a n ( s )

L o s s o f F D t a n ( s )

C o m b u s t i o n a i r f l o w l o w

E x c e s ~ f u r n a c e p r e s s u r e

L o s s o f a l l f l a m e

P a r t i a l l o s s o f f l a m e i n t r o d u c i n g h a z a r d

A l l f u e l I n p u t s z e r o

M a n u a l t r i p I ~ w l t c h

C~as f u e l t r i p ( 5 ~ F i Q u r ~ 6 - 6 . ~ . 1 .1 ) I

c? .

c? ~ -

c?

c? I'~_J C o a l t u e l f r t p ( s e o F J o u r e a - 6 , 3 . 1 . 1 ) I

I g n i t e r f u e l t r i p ( C l a s s 1 i g n i t e r s ) I

J L o w m a i n o i l b u r n e r p r e s s u r e

1 2 b . [ A t o m i z i n g m e d i u m p r e s s u r e i m p r o p e r

I L o s s o f i n d i v i d u a l b u r n e r f l a m e w i t h 13 . o n e o r m o r e a d d i t i o n a l s t a b l e b u r n e r

f l a m e s p r e s e n t

F u r n a c e p u r g e s y s t e m

i ................. I I ............ a n d i n d i v i d u a l i g n i t e r h e a d e r e n d ~ f e t y s h u t o f f v a l v e s : - i n d i v i d u a l Oi l b u r n e r c l o s o d ? Y e s ~ f e t y s h u t o f f

v a l v e s c l o ~ ?

I C l o s e i n d i v i d u a l ignitor I -~ s a f e t y s h u t o f f v a l v e ( s )

a n d d e e n e r g t z e to , a rks

I I g n i t e r f u e l t i p f o r C l a ~ 1 I • I g n i t e r s . b l o c k 11o I

I C l o s e I n i t e r h e a d e r I a n d i n ~ l r i d u a l i g n i t e r =- s a f e t shutoff v a l v e s a n d ~ Y ~ e n e r g i z e s p a r k 8

C l o s e m a i n oil s a f e t y s h u t o f f v a l v e ( s ) a n d I i n d i v i d u a l b u r n e r I m t e t y s h u t o f f v a l v e l L

TO o t h e r f u e l s I s ~ F l o u ~ s I 8 ~ . 3 . 1. 1)

q ~ ° i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ff v a l v e ( s ) I a n d i n d i v i d u a l i g n i t e r ~ f e t y ~ h u t o f f v a l v e ( s ) a n d d o e n e r g i z e a s ~ . o c i a t e d ~pa r l<~

a r e a l l u l v e r i z e r s a r e a l l m a i n g a s t r i p p t l l ~ p a l I h e a d o r a n d i n d i v i d u a l t o f u r n a c ~ s t o p ~ . g a s b u r n e r s ~ f e t y a n d a l l ~ f e l y ~ u t o f f ~hutoff v a l v e s c l o s e d ? v a l v e s c Io r~S)d ?

r ~ l s t e r s o p e n ? F D f a n s r u n n i n g ? a t p u r g e r a t e ? d e l a y t r i p r e l a y ( s )

Figure 7-6.3.1.1 Interlock system for oil-fired multiple burner boiler.

(Log #70) 8502- 50 - (7-6.3.1,1 (b)): Accept in Part SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Block 2a represents conditions... (add after the last sentence) A master fuel trip shall be actuated if the igniters are Class I and no other fuel is in service." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept in Part.

Revise Section 7-6.3.1.1 (b) as follows: Change "Block 2" to "Block 2a". Reject adding the proposed sentence "A master fuel trip shall be actuated if the igniters are Class I and

no other fuel is in service." COMMITTEE STATEMENT: The rejected sentence is adequately addressed in the new diagram covered by Proposal 8502-58 (Log #57). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #71) 8502- 60 - (7-6.3.1.1 (c)): Accept in Part SUBMITTER: W. Scott Matz, Triconex Systenps Inc. RECOMMENDATION: Revise text to read as follows:

"(in the last line) Block 2b. A master fuel trip shall be actuated if the igniters are Class I and no other fuel is in service." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept in Par~

[ Revise Section 7-6.3.1.1 (c) as follows: I Change "Block 3" to "Block 2b". I Reject adding the proposed sentence [ "A master fuel trip shall be actuated if the igniters are Class I and [ no other fuel is in service."

COMMITTEE STATEMENT: The rejected sentence is adequately addressed in the new diagram covered by Proposal 8502-58 (Log #57). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:


ALVEY: Editorial Comment: It appears that the necessary correction to 7-6.1.1(d) was omitted by oversight. To be consistent with Figure 7-6.3.1.1, this Section [7-6.1.1 (d)] needs to have the words "Blocks 1 through 3" changed to "Blocks 1 through 2b".

(Log #72) 8502- 61 - (7-6.3.1.1(e)): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"(e) Blocks 3 through 12 represent conditions... (in the sixth line) Whenever the master fuel Irip." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept.

The following editorial changes are needed: The period after the term "master fuel trip" is not part of the

proposed change and should be removed. The term "(in the sixth line)" is not part of the proposal wording.

It is a direction to editorial staff. Text will now read as follows: (e) Blocks 3 through 12 represent conditions that initiate the

tripping of both the main and ignition fuel supply through a master fuel trip rday. The master fuel trip relay shall be of the type that stays tripped until the furnace purge system allows it to be reset, as shown at the bottom of Figure 7-6.3.1.1. Whenever the master fuel trip relay is operated, it trips all safety shutoff valves, the circulating valve, and the recirculating valve and deenergizes sparks and all ignition devices within the unit and flue gas path. If the design of the fuel oil supply system is such that backflow of oil through the recirculating valve is inherently impossible or positively prevented, this valve shall be permitted to be manually

127

N F P A 8 5 0 2 - - F9 8 R O P

operated and shall not be required to be interlocked to close automatically on a master fuel trip. The interlocks are as follows: NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #73) 8502- 62 - (%6.3.1.1(e)1): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 3 and 4 represent... (in the fourth line make a note t h a t starts with) The loss of one induced." SUBSTANTIATION: The control and tripping philosophy of individual induced and forced fans is design specific. COMMITTEE ACTION: Accept in Principle.

] Revise the text of Section 7-6.3.1.1(e)1 to read as follows: I 1. Blocks 3 and 4 represent protection against loss of large [ quantities of combustion air. The loss of all induced draft fans or [ all forced draft fans shall operate the master fuel trip relay.

COMMITTEE STATEMENT: The text deleted by the Committee Action is included in Section 4-5. Refer to Proposal 8502-13 (Log #51). This meets the intent of the submitter. The addition of the term "master" before the term "fuel trip relay" is to provide consistency with the text in Section 6-6.3.1.1 (d)1. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #74) 8502- 63- (7-6.3.1.1(e)2): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 5 represents low...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept.

I Editorially delete the "s" in the word "blocks". The revised text should read: "Block 5 represents low combustion airflow below the permitted

limits and is interlocked to activate the master fuel trip relay." NUMBER OF COMMrVFEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25


"Excess furnace pressure (Block 6) also...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure %6.3.1.1. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #76) 8502- 65 - (7-6.3.1.1(e)4): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 9 represenis an interlock...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept.

Editorially delete the "s" in the word "blocks". The revised text should read: "Block 9 represents an interlock operation when all fuel input to

the furnace are shut off following ashutdown of file boiler for any r e a s o n .


AFFIRMATIVE: 25

(Log #77) 8502- 66 - (7-6.$.1.1(e)5): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

~qThen the main burner header fuelpressure (Blocks 12a) is below the minimum for stable flame, that fuel shall be tripped. If it is the only fuel in service (Blocks l l a , l l b , and l l c ) the master fuel trip relay shall be actuated. See Table 7-5.2.5.2(a), item (a)." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept in Principle.

Revise the submitter's proposal to read as follows: ~When the oil burner header fuel pressure (Block 12a) is below

the minimum for stable flame, that fuel shall be tripped. If oil was the only fuel in service (Blocks l l a , l l b , and 11c) the masterfuel trip relay shall be actuated. See Table 7-5.2.5.2(a), item (a). COMMITTEE STATEMENT: Editorially revised to clarify meaning. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:


MILONE: In both the original Proposal and Committee Action the last sentence in this paragraph refers to Table 7-5.2.5.2(a), item (a). This table has not been revised to incorporate the oil fuel trip. Two separate tables should be provided, one entitled Mandatory Automatic Fuel Oil Trips and the Other entitled Automatic Master Fuel Trips. Also, existing Table 7-5.2.5.2(b) should be renumbered as 7-5.2.5.2(c).

Table %5.2.5.2(a) should read: A fuel oil trip shall result from either of the following conditions:

(a) Fuel and atomizing medium... (b) Last individual burner safety shutoff valve closed.

MFI" Table %5.2.5.2(b) should be the same as currently exists with the following exception:

1. Rel~lace the text in (a) with "All fuel trip relays (including Class 1 ignitor trip) activated"

2. Omit (g).

(Log #78) 8502- 67- (7-6.3.I.1(e)6): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

~Blocks 12b represents operation of the fuel trip relay to prevent an unsafe condition developing from improper atomization of the oil. Ifoil is the only fuel in service (Blocks l l a , 11b, and 11c) the master fuel trip relay shall be actuated. See Table 7-5.2.5.2(a), item (a)." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept in Principle.

Revise the submitter's proposal to read as follows: "Block 12b represents operation of the oil fuel trip to prevent an

unsafe condition developing from improper atomization of the oil. Ifoil was the only fuel in service (Blocks l l a , l i b , and l l c ) the master fuel trip relay shall be actuated. See Table 7-5.2.5.2(a), item (a). COMMITTEE STATEMENT: Editorially revised to clarify meaning. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #79) 8502- 68 - (7-6.3.1.1(e)7): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 10 represents a manual...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept. Editorially delete the ~s" in the word "blocks".

The revised text should read: ~Block 10 represents a manual switch that can be used by the

operator in an emergency to actuate the master fuel trip relay." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

128

N F P A 8 5 0 2 - - F 9 8 R O P

(Log #80) 8502- 69- (7.6.3.1.1(e)8): Accept SUBMITTER= W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 7 represents loss of...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7.6.$.1.1. COMMITTEE ACTION: Accept.

I ditorially delete the "s" in the word "blocks". The revised text should read: "Block 7 represents loss of all flame in the furnace and is

interlocked to activate the master fuel trip relay." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25


"Blocks 8 represents a partial loss of...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept.

Editorially delete the "s" in the word "blocks . The revised text should read: "Block 8 represen~ z partial loss of flame to the extent that

hazardous conditions could develop irrespective of, or due to the i failure of, other protective interlocks." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25. VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #82) 8502- 71 - (7-6.3.1.1 (t,)): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 13 represents loss of flame... (in the fifth line) 7- 6.$.1.1(e)9 (Block 8). This trip...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 7-6.3.1.1. COMMITTEE ACTION: Accept in Principle.

Revise Section 7-6.3.1.1(f) as follows: In the first line change "Block 15" to "Block 13". In the fifth line change "Block 12" to "Block 8".

COMMI~I'F.R STATEMENT: The revised text meets the intent of the submltter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

E Igeit~' saf*ty shutoff v ~ w W F lOml, r lu*l ,:¢t,~'ol vel~ ~I ~+ O IndlW~elloni~r~mfe~]r, hutoffvelv. ~ - . O Clearer or s t re i~ m,dum . . . . I S Fu¢l p r ~ ~ I T M~ua4 r, hutoffvdve I

0 Y

~0#y "r- t b, : ~- "d

in6t~lad)

Figure A-7.8.1.1(a) Typical mechanical atomizing light oil igniter system (diagram) - supervised manual.

E Ignilmr ~ f e ~ / ~ o l f rely* W F Ignitor (u~ oonlrol valve ~ ~._LrJ O Individual i~i tof safety shutoff veJve : _ ~ O CJtanof of slrainet' meeltm~ " ~ Fuel presr, ure gat~e

Manual shutoff rely* W S~v*eglng valv* y Check veJVe Z Diff,r,mial pr*~ure ~ I t o l wlve Z 1 A t o m i ~ meeis prelsuro g,mlJ~ O Y Y~ Z,

' -0 o, ~ . o. ~ ~ . . . . . . . . . . . . . . . . . . . . . . ¢ ~ : z

Figure A-7-8.1.1(b) Typical steam or air atomizing l ight ol l igniter system (diagram) - supervised manual.

COMMITTEE STATEMENT: This action meets the intent of the submitter. Revisions have been made to add references and to

rovide an actual diagram for inclusion in the document. UMBER OF COMMITFEE MEMBERS ELIGIBLE TO VOTE: 25

VOTE ON COMMITTEE ACTION: AFFIRMATIVE: 24 NEGATIVE: 1

EXPLANATION OF NEGATIVE: WILI_.SE: The sketch shows the Low Pressure Switch on the oil

line for igniters has been removed. Table 7-5.2.5.2(a) requires a mandatory fuel trip if the fuel and atomizing medium is outside the operating limits. We need to keep the low oil pressure switch on the sketch.

(Log #8) 8502- 72 - (7-8): Accept in Principle SUBMITTER: Bill Bass, Forney Corp. RECOMMENDATION: Revise text as follows:

Correct the references to appendix fi~ures. Figure A-7-8.1.1 is the correct figure for supervised manual od burner system. There is no figure specifically for supervised manual oil igniter system. Create a figure similar to that used for supervised manual gas isgl~Biter system (A.8-5.1.1 (a)).

STANTIATION: Entire 7-8 section refers to wrong appendix diagrams. COMMITTEE ACTION: Accept in Principle.

Revise the submitter's proposal to read as follows: J In Sections 7-8.2.1 through 7-8.2.9; [ Change reference to figures from [See Figures A-7-5.1.2(a) and I (d).] to [See Figures A-7-8.1.1(a),(b) and (c).] ] In Appendix A change Figure A-7-8.1.1 to Figure A-7-8.1.1 (c). ] In Appendix A add a new Figure A-7-8.1.1 (a) and (b) as shown I below.

(Log #C211) 8502- 72a- (7-8.2,9(d)3 and 7.8.2.9(d)4): Accept SUBMITTER= Technical Committee on Multiple Burner Boilers RECOMMENDATION: In Section 7.8.2.9(d)3 delete the term "post-firing". Text will now read as follows:

3. If the airflow is above purge rate, it shall be permitted to be . . . . = -" - - unit purge shall decreased gradually to this value and a r . . . . . . . . . 6

be performed. In Section 7.8.2.9(d)4 delete the term "post-firing"o Text will now

read as follows: 4. If the airflow is below purge rate at the time of the trip, it shall

be continued at the existing rate for 5 minutes and then increased gradually to purge rate and held at this value for a pc~=.~:"xg unit .

I u r e . p "ge SUBSTANTIAl'ION: Committee intent is to require a purge of not less than 5 minutes, or five changes in volume of the boiler enclosure, whichever is longer. This is the definition of "Unit Purge".


AFFIRMATIVE: 25

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N F P A 8 5 0 2 - - F98 R O P

(Log #3) 8502- 73 - (7-9.1.2): Reject SUBMITTER: Lalit M. Mehta, Coen Co., Inc. RECOMMENDATION: Add to the end of the sentence, "(See NFPA 8501, Standard for Single Burner Boiler Operation)."

Designer shall take in consideration boiler common interlocks for boiler MFT, and boiler purge. SUBSTANTIATION: It is not clear (as is in 7-9.1.3) that NFPA 8501 applies. Sections 7-9.1.2 and 7-9.1.3 text will then match. MFT should be to both burners and designer should address that part of the interlock and boiler purge interlock. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: NFPA 8501 does not apply to this

OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #34) 8502- 74- (8-5.2.1): Accept SUBMITTER: George Y. Keller, Burns & Roe RECOMMENDATION: Revise Section 8-5.2.1 to read asfollows:

8-5.2.1 Cold Start. This section covers the requirements for placing coal in service as the initial fuel being fired. Section 8-

.2.6 covers the requirements for placing coal in service as a subsequent fuel. SUBSTANTIATION: This addition clarifies the difference between first and subsequent fuels. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #27) 8502- 75 - (8.5.2.1.1): Accept SUBMITTER: John P. O'Rourke, ABB Combustion Engineering, Inc. RECOMMENDATION: In Section 8-5.2.1.1, replace existing subsections (f) through (k) with the following:

"(f) The proper drum water level is established in drum-type boilers, andcircula t ing flow is established in forced circulation

boilers , or minimum water flow is established in once-through boilers.

(g) The oxygen analyzer(s) and combustibles analyzer(s), if ! provided, are operating satisfactorily and a sample has been obtained. Combustibles indication is at zero and oxygen indication is at maximum.

! (h) The ignitor safety shutoff valves are closed and sparks are I deenergtzed [see Figures A-8-5.2(a) through (c) ] . For gas ignition systems, see Chapter 6; for oil ignition systems, see Chapter 7.

I (i) The pulverizing equipment is isolated effectively to prevent [ inadvertent or uncontrolled leakage of coal into the furnace.

(j) The pulverizers, feeders, and associated equipment are in good condition and adjusted properly to be ready.for service. All pulverizer and feeder sensor lines are clean prior to starting.

(k) Energy is supplied to control system and to safety interlocks." SUBSTANTIATION: Sections were renumbered to organize items for multiple fuel firing startup sequences. COMMITTEE ACTION: Accept.

I Editorially change the term "ignitor" to "igniter" in subsection (h). [ The revised text should read: [ (h) The igniter safety shutoffvalves are closed and sparks are ] deenergized [see Figures A-8-5.2(a) through (c)]. For gas ignition [ systems, see Chapter 6; for oil ignition systems, see Chapter 7.

NUMBER OF COMMITTEE MEMBERS ELIGIBLE TOVOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #39) 8502- 76 - (8-5.2.2.4(a), (b), and (c) (New)): Accept SUBMITTER: Francisco A. Palacios, D B Riley, Inc.

I RECOMMENDATION: Add the word "coal" to sentences (a) and (b) and add sentence (c) under Section 8-5.2.2.4. Changes will read:

(a) With all ~;0~[ burners in service and combustion controls on automatic,

I (b) With different combinations of ¢971 burners in service and combustion controls on automatic,

and (~) With different combinations of ~as. oil. and coal burners in service and combustion controls on automatic. SUBSTANTIATION: Normal operation of firing coal (Section 8- 5.2.2) appears to apply for both single and dual fuel. The only appropriate change is to add a requirement in 8-5.2.2.4 stating that trial tests should be done for dual fuel firing. Adding the word "coal" to the existing text is for clarity. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #19) 8502- 77- (8-5.2.3): Accept SUBMITTER= RaymondJ. Heitland, Monsanto Co.

I RECOMMENDATION: Revise Section 8-5.2.3 as follows: 8-5.2.3 Normal Shutdown. This section covers the requirements

[ for removing coal from service as the only fuel being fired. Section 1 8-5.2.7 covers the requirements for removing coal from service with [ other fuel remaining in service.

SUBSTANTIATION: This addition clarifies the difference between multiple and single fuel operation and directs the reader to the appropriate section. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #30) 8502- 78 - (8-5.2.3): Accept SUBMITrER: Dale E. Dressel, Monsanto Co. RECOMMENDATION: Revise Section 8-5.2.3 to read as follows:

8-5.2.3 Normal Shutdown. This section covers the requirements for removing coal from service as the only fuel being fired. Section 8-5.2.7 covers the requirements for removing coal from service with other fuel remaining in service. SUBSTANTIATION: With the intent to add simultaneous multiple fuel firing, to the standard, a normal shutdown of coal with coal only being fired and a normal shutdown of coal only when other fuels are still being fired must be distinguished. The proposed revision, along with other committee proposals that are being submitted, will address the changes required to properly address both situations. COMMITTEE ACTION: Accept. NUMBER OF COMMITI~EE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

8502- 79 - (8-5.2.3.1 through 8-5.2.3.3): Accept (Log #31) SUBMITrER: Dale E. Dressel, Monsanto Co. RECOMMENDATION: Revise Section 8-5.2.3.1 through Section 8- 5.2.3.3 as follows:

8-5.2.3.1 When taking the unit out of service, the boiler load shall be reduced to that necessitating a purge rate airflow using the procedures outlined in Sections 8-5.2.3.2 and 8-5.2.3.3.

8-5.2.3.2 A pulverized fuel system shall be shut down in file following sequence:

(a) Pulverizer's fuel input, airflow, and register positions shall be adjusted to values established for start-up.

(b) Igniters shall be placed into service at these burners, when required to maintain flame stability.

(c) The hot primary air shall be shut o f fand the cold primary air shall be opened to cool down the pulverizer. (See NFPA 8503, Standard for Pulverized Fuel Systems, for detailed information on pulverizer cooling.)

(d) The feeder shall be stopped in accordance with the manufacturer's recommendation. Operation of the pulverizer shall be continued with sufficient airflow to empty out the pulverizer and associated burner lines.

(e) The inerting medium shall be introduced into the pulverizer as dictated by the coal characteristics.

(f) The pulverizer subsystem shall be shut down when burner fires are out and the pulverizer is empty and cool.

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N F P A 8 5 0 2 m F 9 8 R O P

(g) All individual burner line shutoff valves shall be closed unless otherwise directed by the manufacturer's instructions.

(h) Igniters shall be removed from service. 8-5.2.3.3 As the fuel is reduced, the following procedures shall

be followed: (a) The remaining pulverizers shall be shut down consecutively

following the procedures of 8-5.2.3.2(a) through (h). (b) In cases where the next pulverizer being removed could

result in flame instability, igniters shall be placed into service on burners that are still being fired. SUBSTANTIATION: The phrase in the existing Section 8-5.2.3.1 refers to using the "reverse procedure of that used during start-up" for a normal shut down. This is not very clear and could be misinterpreted. In Section 8-5.2.3.2, the term "combustion control" is too broad to adequately describe the desired actions during normal shut down of the pulverizer system. With the intent to add simultaneous multiple fuel firing to the standard, a normal shutdown with coal only being fired and a normal shut down of coal only when other fuels are still being fired must be distinguished. The proposed revisions, along with other committee proposals that are being submitted, will address the changes required to properly address the issues. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #15) 8502- 80 - (8-5.2.5.3 and 8-5.2.5.4): Accept in Principle SUBMITTER: Bill Bass, Forney Corp. RECOMMENDATION: Change "post-firing unit purge" to "unit

~ urge'. UBSTANTIATION: Some system designers ( and some end

users) believe there is a difference between a "post-firing unit purge" and a normal "unit purge". As a result, those systems require the operator to .perform a 5 minute "post-firing unit purge" followed by a 5 minute -unit purge" for a total of ten minutes of purging after a master fuel trip. I do not believe that is the intent of the standard. COMMITTEE ACTION: Accept in Principle.

In Section 8-5.2.5.3: In the third sentence change the term "post-firing" to "unit". In the last sentence delete the term "post-firing". In Section 8-5.2.5.4: In the last sentence delete the term "post-firing".

COMMITTEE STATEMENT: Additional changes are required to meet the intent of the submitter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMAtiVE: 25

(Log #24) 8502- 81 - (8-5.2.6 (New)): Accept SUBMITTER: Blair Kerstetter, The Foxboro Go. RECOMMENDATION: Add new text as follows:

8-5.2.6 Starting Sequence Second Fuel. 8-5.2.6.1 When starting coal as a second fuel, the requirements of

8-5.2.1.1(11) through 8-5.2.1.1(k) shall he satisfied, see 8-5.5.9. 8-5.2.6.2 The starting sequence of the first fuel (gas or oil) shall

be complete. The starting sequence of second fuel (coal) shall be

~ erformed in the starting sequence in 8-5.2.1.3(e) through (t). UBSTANTIATION: Section 8-5.2.1 describes the cold start

sequence of pulverized coal as the first fuel fired. While portions of the cold sequence applies to the second fuel start sequence, a new Section (8-5.2.6) titled "Starting Sequence Second Fuel" is recommended for clarity. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25


8-5.2.7 Shutdown Sequence Second Fuel. This section covers the requirements for removing coal from service with other fuel remaining in service. Section 8-5.2.3 covers the requirements for removing coal from service as the only fuel being fired.

8-5.2.7.1 When shutting off coal with gas or oilremaining in service, a sequential shutdown of coal shall be accomplished in accordance with 8-5.2.3.2 and 8-5.2.3.3. SUBSTANTIATION: Section 8-5.2.3 describes the normal shutdown of coal when firing as a single fuel. While the normal shutdown sequence applies to the second fuel's shutdown, a new Section (8-5.2.7) titled "Shutdown Sequence Second Fuel" is recommended for clarity. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #7) 8502- 83- (8-5.4.9): Accept

I SUBMITTER: Bill Bass, Fomey Corp. RECOMMENDATION: Add Section 8-5.4.9 to read:

8-5.4.9 The total heat input within a burner or furnace zone, or both, shall not exceed the maximum limits specified for the equipment. Special consideration shall be given where a burner or furnace zone, or both, simultaneously fires more than one fuel. SUBSTANTIATION: Since 8502 covers multiple fuel firing, burner heat input limits are an operating requirement when considering fuel transfer or dual fuel firing. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:


ALVEY: Editorial Comment: 8-5.4.9 should be 8-5.5.9.

(Log #58) 8502- 84- (Figure 8-6.3.1.1): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc.

[ RECOMMENDATION: Revise figure as shown on page 132: SUBSTANTIATION: Revised to address multiple fuel firing in the boiler. COMMITTEE ACTION: Accept. COMMITTEE STATEMENT: The following editorial changes are needed:

Throughout the figure, change the term "ignitor" to "igniter". In the second bloi:k in the upper right hand comer change the

term "tip" to "trip". NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #83) 8502- 85 - (8-6.3.1.1(b)): Accept in Part SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Block 2a represents conditions... (add after tile last sentence) A master fuel trip shall be actuated if the igniters are Class 1 and no other fuel is in service." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept in Part.

Revise Section 8-6.3.1.1(b) as follows: Change "Block 2" to "Block 2a'. Reject adding the proposed sentence "A master fuel trip shall be actuated if the igniters are Class I and

no other fuel is in service." COMMITTEE STATEMENT: The rejected sentence is adequately addressed in tile new diagram covered by Proposal 8502-84(Log #58). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

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N F P A 8 5 0 2 - - F9 8 R O P

C o a l f u e l t r i p s y s t e m

1 . I LOSS el igni ter l lama |

2a. I I gn i te r fuel p ressure OUt of s table range

2b. I igni tor a tomiz ing med ium pressure ,mproper

3. LOSS o t l ~ lan(~)

4. Loss of FD tan(s)

5. Combust ion air f low low

6 Exco6s fu rnace pressure

7. LOSS of all f lame

8. part ia l toffs of f lame int roducing hazard

9. All tuel inputs zero

1 O, Manua l tr ip switch

11 a. Gas fuel tr ip ( s e e F l O u r e 6 - 8 . 3 . 1 . 1 ) I

11b. C)ll f u e l t r l p ( s o e F / g u r e 7 - 6 . 3 . 1 . 1 ) I

11 o. Igni ter fuel trip (Class 1 ignitors) l

All COal fir ing equl mont I 12. s topped or t r l pp~Por c o m m o n

coal f ir ing equ ipment t r ipped

<p

<p

~P I - J -

cp

I

.. I C lose tndividlJal igni ter I sa fe ty shutoff va lve(s)

I and d e e n e ~ i z e sparks

Igni ter fuel t ip for Class 1 I l

1 I g n i t e r s , blo~k 11 c { I C lose i ni ter header I and in~lVridual igniter

= satet shutoff va lves I and ~/~ene~liZe sparks I

~ _ I S top coal f low to putvor |zevs I and burners

. ( s e e F i o u r e 8

- J - I . . . . . . . . . . . i 7 - 6 . 3 . 1 . 1 )

F u r n a c e p u r g e s y s t e m

I aA~¢~ . . . . . . . . . . . . . . . ~ . . . . . I p . . . . . . . . . P H . . . . . . . . . . . f . . . . . H . . . . . . . . . . . . . . . . h indlv ldual , lgni ter t r ipped, all Coal f low are all main gas are all main oil

sa fe ty shutoff va l ves to fu rnace s lop c O . header and indiv idual heade r and indiv idual OloKe'd? aod a4l safety shutof f o|l bu rner safe ty gets burner safe ty

va l ves dosed'#' shutof f va l ves c losed? shutof f va l ves Closed?

Is air f low 5-mlnute t ime Reset mas te r fuel de lay tr ip re lay(s)

Figure 8-6.3.1.1 Master fuel trip system. Block diagram for furnace interlocks for a pulverized coai-flred multiple burner boiler (see 8-63.1).

(Log #84) 8502- 86 - (8-6.3.1.1 (c)) : Accept in Part SUBMITTER: W. Scott Matz, Tr iconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"(in the last line) Block 2b. A master fuel trip shall be actuated if the igniters are Glass I and no o ther fuel is in service." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept in Part.

I Revise Section 8-6.3.1.1 (c) as follows: Change "Block 3" to "Block 2b". Reject adding the p roposed sentence "A master fuel trip shall be actuated if the igniters are Class I and

no other fuel is in service." COMMITTEE STATEMENT: The rejected sentence is adequately addressed in the new diagram covered by Proposal 8502-84(Log #58). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #85) 8502- 87 - (8-6.3.1.1 (d)): Accept SUBMITTER: W. Scott Matz, Tr iconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"(d) BlocKs 3 through 12 represent conditions.. . (in the sixth lirie) Whenever the master fuel trip." SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept.

Tbe following editorial changes are needed: The per iod after the term "master fuel trip" is no t part of the

p roposed change and should be removed. The term "(in the sixth line)" is no t part of the proposal wording.

It is a direction to editorial staff. Text will now read as follows:

(d) Blocks 3 through 12 represent conditions that initiate the tripping of both the main and ignition fuel supplies through a master fuel trip relay. T he master fuel trip relay shall be of the type that stays tripped until file furnace purge system allows it to be reset, as shown at the bottom of Figure 8-6.3.1.1. Whenever the master fuel trip relay is operated, it trips all coal burner line shutoff valves or equivalent functional action to stop coal delivery to burners, primary air fans or exhausters, and coal feeders and deenergizes all sparks And all ignition sources within the unit and flue gas path. The interlocks are as follows: NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #86) 8502- 88 - (8-6.3.1.1(d)1): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks ~, and 4 represent... (in the fourth line make a note that starts with) The loss of one induced." SUBSTANTIATION: The control and tripping philosophy of individual induced and forced fans is design specific. COMMITTEE ACTION: Accept in Principle.

Revise the text of Section 8-63.1.1(d) 1 to read as follows: I 1. Blocks 3 and 4 represent protection against loss of large ] quantities of combustion air. The loss of all induced draft fans or | all forced draft fans shall operate the master fuel trip relay.

COMMITTEE STATEMENT: The text deleted by tile Committee Action is included in Section 4-5. Refer to Proposal 8502-13 (Log #51). This meets the intent of the submitter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

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N F P A 8 5 0 2 - - F9 8 R O P

(LOg #87) 8502- 89- (8-6.3.1.1(d)2): Accept SUBMITI'ER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks'5 represents low...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept.

I Editorially delete the "s" in the word "blocks". The revised text should read: "Block 5 represents low combustion airflow below the permitted

limils and is interlocked to activate the master fuel trip relay." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25


"Blocks 8 represents a partial loss of...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITrEI/I ACTION: Accept.

Editorially delete the "s" in the word "blocks". The revised text should read: "Block 8 represents a partial loss of flame to tire extent that

hazardous conditions could develop irrespective of, or due to the failure of, other protective interlocks." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

CLog #88) 8502- 90 - (8-6.3.1.1(d)3): Accept SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Excess furnacepressure (Block 6) also...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25


"Blocks 9 represents an interlock...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept.

Editorially delete the "s" in the word "blocks". The revised text should read: "Block 9 represents an interlock operation when all fuel inputs to

the furnace are shut off following a shutdown of the boiler for any reason." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

f

(Log #90) 8502- 92 - (8-6.3.1.1(d)5): Accept SUBM1TTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 10 represents a manual...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept.

Editorially delete the "s" in the word "blocks". The revised text should read: "Block 10 represents a manual switch that can be used by the

tor in an emergency to actuate the master fuel trip relay." ER OF COMMrI~I'EE MEMBERS ELIGIBLE TO VOTE: 25

VOTE ON COMMITTEE ACTION: AFFIRMATIVE: 25


"Blocks 7 represents loss of...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept. Editorially delete the "s" in the word "blocks".

The revised text should read: "Block 7 represents loss of all flame in the furance and is

interlocked to activate the master fuel trip relay." NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

(Log #93) 8502- 95 - (8-6.3.1.1(d)8): Accept in Principle SUBMITTER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Add new text to read as follows:

"Blocks 12 represents the tripping/shutdown of coal firing equipment that will cause a coal fuel trip. If coal is the only fuel in service (Blocks l la , l lb , and l lc ) the master fuel trip relay.shall be actuated." SUBSTANTIATION: Added to address multiple fuel firing in the boiler per Figure 8-6.3.1.1. COMMITTEE ACTION: Accept in Principle.

[ Revise the submitter's proposal to read as follows: I "Block 12 represents the tripping/shutdown of coal firing [ equipment that will cause a coal fuel trip. If coal was the only fuel [ in service (Blocks l la , 11b, and 11c) the master fuel trip relay shall [ be actuated."

COMMI'FI'EE STATEMENT: Editorially revised for consistency with Section 7-6.3.1.1(e)6. Refer to Proposal 8502-67 (Log #78). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:


MILONE: To be consistent with oil and gas trips, add the sentence: "Refer to Table 8-5.2.5.2(a)". This table must now be revised to incorporate the coal fuel trip. Two separate tables should be provided, one entitled Table 8-5.2.5.2(a) Mandatory Automatic Coal Fuel Trips and the other entitled 8-5.2.5.2(b) Mandatory Automatic Master Fuel Trips. Also, existing Table 8- 5.2.5.2(b) should be renumbered as 8-5.2.5.2(c).

TabJe 8-5.2.5.2(a) should read: "A coal fuel trip shall result from the following condition:".

All coal firing equipment stopped or tripped or common coal firing equipment tripped.

The MF]" Table 8-5.2.5.2(b) should be the same as currently exists except for the change in numbering.

(Log #94) 8502- 96 - (8-6.3.1.1(e)): Accept SUBMII~I'ER: W. Scott Matz, Triconex Systems Inc. RECOMMENDATION: Revise text to read as follows:

"Blocks 13 indicates that, on loss of...". SUBSTANTIATION: Revise to address multiple fuel firing in the boiler per Figure 8-6.$.1.1. COMMITTEE ACTION: Accept.

Editorially delete the "s" in the word "blocks". The revised text should read: "Block 13 indicates that, on loss of main burner flame, the

r i l~ngs t ra tegy of 8-4.4.2 shall be followed." BER OFCOMMITTEE MEMBERS ELIGIBLE TO VOTE: 25

VOTE ON COMMI'FrEE ACTION: AFFIRMATIVE: 25

(Log #CP10) 8502- 96a - (A-6-2(c).ll.E(c)): Accept SUBMITTERa Technical Committee on Multiple Burner Boilers

[ RECOMMENDATION: In Section A-6-2(c)II.E(c),in the first [ paragraph following (c): ] Beginning with the third sentence change the paragraph to read ] as follows: | "...purge rate, it may be permitted to be decreased gradually to | this value for a unit purge, ff the airflow is below purge rate at the

133

N F P A 8 5 0 2 ~ F9 8 R O P

l time of the trip, it should be continued at the existing rate for 5 minutes and then increased gradually to purge rate and held at this value for a unit purge." SUBSTANTIATION: Committee intent.is to~ require a purge of not less than 5 minutes, or five changes in volume of the boiler enclosure, whichever is longer. This is the definition of "Unit Purge".


AFFIRMATIVE: 25

(Log #52) 8502- 97 - (A-6-5.2.1.3): Reject SUBMITTER: Todd Sommer , EER Corp. RECOMMENDATION: Revise I-D to read as follows:

"...distribution of flows to the burners; the type of main burner flame detector(~L their location, and their sighting should be assessed and retested."

Add a new I-E to read as follows: "The design of a staged fuel infection system (if applicable)

should be reviewed and tested to ensure adeauate iniection velocities of the staged fuel and associated over-fire air for nroner mixing and nroner intet~ration with the combustion controls and Burner Management System. Tile location, direction, and velocity of fuel iniectors should be determined bv a combination of isothermal and comoutational flow modelin~ technioues."

Add a new I-F to read as follows: "Enough combustion air must be suoolied, via over-fire air norts

or other means, so that the total excess air leaving the furnace meet~ the exc¢~ air reuuirements snecified in N#PA 8502."

Add a new II-A(c) to read as follows: "Where staged fuel injection is used. the desima of the fuel

inje¢~0rs should be revi¢wed to ensure n roner ioca t ions and adeauate injection velocities at all boiler onerat ing loads f o r intimate mixing of the staged injection fuel with the products of combustion fro~m the main burner zone. The desitrn" of the system over-fire air norts (if necessary) should be reviewed to ensure oroner locations and adeauate injection velocities to ensure the comoletion of combustion of any unbu rned hydrocarbons from the t:urr~ace. The sta~ed fuel injection system should be integra~t~l with the main fuel combustion-controls and bu rne r management system ~o ensure proper ratios of fuel and coml~ustlon air are maintained and interlocked to nrevent the accumulation of unbu rned combustibles in the iaoiler settin~ at all boiler loads. Iniection nort flame scanners are not renuired oroviding alternate interlocks are orovided to nrove safe condit ions are oresent for ~he introduction of the sta~¢d i~ec t lon fuel."

Renumber lI-A(c) to II-A d.(d3_. Add a new Section III - Staged Combustion to read as follows: "A number of new firing configurations that have been

successfully applied to fossil fuel fired boilers involve the "stag~l" injectiO[l of fuel outside the boundarv of the classical bq fne r a n d / o r burner zone. Basically. "staged" fuel inlection systems require that fuel. in the absence of stoit;lfiometric air. b~ inieet¢¢l into the furnace outside of tile main fuel burning zone - creating a gone of reduced excess air or even substoichiorB~etric t;9oditio[ls, NO x molecules formed in the main burner zone are reduced in dais manner. Over-fire air may or may not be added downstream of the "staged ~ fuel iniection denending on the ouantitv of combustion ,air reouired to oxiclize any unbu rned hydrocarbons. .

These final bu rnou t reactions occur under normal excess air conditions.

It should be noted that the ouantitv of "sta~ed" fuel m~,y be a s high as thirtv (30) nercent of the total fuel innut to ti~e boiler on BTU basis. The main tggt of NFPA 850~ addresses the r ecommended interlocks for tile main burners for safe ooeration. Included in these r ecommended interlocks are references to flame detectors - where they should be used - and certain excentions where they may not be directly tied to fuel tr inning svstems (i.e.. NFPA 8504).

"Staged" fuel iniection may oresent nroblems with the use of f lamedetectors at the "staged" fuel inlection oorts. When fuel is

injected with a minimal a m o u n t of combustion air (in many cases withgut any ~gmbustion air). there is no visual combustion takin~t nlace at the injection Iocation(sL A very ranid chemical reaction does take nlace however, due to the elev~ated'temneratures and raoid mixi'n~ of the "stalted" fuel with the nroducts of combustion from the main burner zone whereby o x w e n in the flue Izas from the main burner zone is almost immediately reduced or ¢;9[18~med. dependin~ on the amoun t of fuel injected. This er~i~[~s a lower excess air condition or. if enough fuel is iniected, a ~ubstoichiometrie zone in the furnace. Over-fire air may ~ e n be added with sufficient velocities to ranidlv comolete the combustion reactions resultin~ in a flue itas comoosit ion similar to that typically found i n d u e gasses/eaving ihe furnace in a conventionally fired boiler. For smaller auantities of "sta~ed" fuel. the amoun t of excess air leavin~ the main combustion zone is adeuuate to comolete the combustion nrocess without a seDarate over-fire air stream.

Flal~ae det¢ftors may not nrovide a useful innut to a burner management svstem in these annlications. I n the absence of flame detectors, other oermissives for ='sta~ed" fuel iniection must be utilized. The key is to find other rel'iable indices that indicate that the t~mperature in the area where the fuel is beinit injected is above the autoi~nltion temperature of the fuel. I ( shou ld be noted that the furnace temnerature in the annronriate location of most furnaces will range from a low of annroximatelv 2000°F to aonroximatelv 28~00°F at boiler loads-over anoroximatelv 50 percent. The actual anticinated temperature must be verified on a ease by case basis, however, temneratures in this ran~e~ are well above the autoitmition temoerature for tvoical fuels.

It is therefore recorr~nencied that the f0ilowin~ interlocks be included for initiation of an or continued "sta~ed ~ fuel iniection o D e F a t i o n :

| , [~oiler [gad resulging in a furnace temperature at the point qf injection of ~reater than 1400°F. (Steam flow or other reliable index).

2. Main fuel firin~ euuinment successfully in service. (The nroof that a significant nu~mber o f main fuel burners a n d / o r oulverizer grg9ps are in service ensures a fairly even temperatur~ ~tistribution in the furnacel.

3, No boiler MFT nresent. 4. Sufficient numbe r of F.D. and I.D. fans in service. (To ensure

even f low/ temoera ture distribution in the furnace). 5. All other normal NFPA fuel firing interlocks associated with

the "~taged, ~ fuel control and delivery, equipment are satisfied, In addition, the analog controls should be desimaed to ensure

that sufficient over-fire air flow is continuously oresent to comnlete the combustion nrocess for the "staged" fuel flow rate (cross limited system),

If the above conditions are continually met. it can be assured that the temperature in the fuel injection zone will be well above the autoi~qaition temnerature of tlqe "sta~ed" injection fuel and. therefore, tile oossibilitv of accumulating asi~nificant volume of an exnlosive mixture of fuel and air will-be nrevented. SUBSTANTIATION: The introduction of new regulations by the EPA concerning the reduction of NO x emissions f rom fossil fuel fired, boilers, has prom. pted .the development of relatively, new and mnovauve fuel f inng techmques. Many of these techmques are applied to new boiler designs, new main fuel burner designs for new boilers or for retrofit to existing boilers, and fuel firing configuration modifications for new a n d / o r existing boilers.

Most of these techniques involve some form of staged combustion where fuel, as well as air, is injected into the furnace in a staged fashion. The fuel staging typically occurs in a manner that does not comply with current standard language regarding the in'ectionij of fuel. throu, g h conventional., burner equiprr ment.

Some modifications and addmons to the current NFPA 8502 standard are necessary to provide guidance for tile safe, reliable application of these new combust ion process modification techniques. This Proposal provides only a suggested framework for beginning discussions on the standard changes required and is primarily intended to initiate the standard revision process. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The proposal is specific to a single manufacturer and may not represent the only approach to reburn technology. This proposal will be referred to the task group assigned to develop new material covering furnace NOxreduc t ions for the Fall 2000 cycle.

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N F P A 8 5 0 2 m F9 8 R O P


AFFIRMATIVE: 25

( Log #CP 12) 8502- 97a - (A-7-8.1I.E(d)): Accept SUBMITTER: Technical Commit tee on Multiple Burner Boilers RECOMMENDATION: In Section A-7-8.ll.E(d),in the first paragraph following (d):

Beginning with the third sentence change the paragraph to read as follows:

"...purge rate, it may be permit ted to be decreased gradually to this value for a uni t purge. If the airflow is below purge rate at the time of the trip, it should be cont inued at the existing rate for 5 minutes and then increased gradually to purge rate and held at this value for a uni t purge."

SUBSTANTIATION: Committee intent is to require a purge of not less than 5 minutes, or five changes in volume of the boiler enclosure, whichever is longer. This is the definit ion of "Unit Purge".

Also see Commit tee Action and Committee Statementon Proposal 8502-53 (Log #14). COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 25 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 25

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national fire protection association · 2010. 6. 17. · rancisco a. palacios, db riley, inc., ma...

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