ss 341-2001

SINGAPORE STANDARD

SS 341 : 2001(ICS 91.100)

SPECIFICATION FOR

Safety glazing materials foruse in buildings (humanimpact considerations)

Published bySingapore Productivity and Standards Board1 Science Park DriveSingapore 118221

Licensed by SPRING Singapore to HUEYYIANG, CHEONG/MS, DDG GLASS PTE LTDSingapore Standards eShop Order No: 6800023373/Downloaded:2013-06-13Single user licence only, copying and networking prohibited

SINGAPORE STANDARD

SS 341 : 2001(ICS 91.100)

SPECIFICATION FOR

Safety glazing materials foruse in buildings (humanimpact considerations)

All rights reserved. Unless otherwise specified, no part of this SingaporeStandard may be reproduced or utilised in any form or by any means,electronic or mechanical, including photocopying and microfilming, withoutpermission in writing from the Singapore Productivity and Standards Boardat the address below:

DirectorCentre for StandardisationSingapore Productivity and Standards Board1 Science Park DriveSingapore 118221Telephone: 2786666 Telefax: 2786665Email: [email protected]

ISBN 9971-67-866-7


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This Singapore Standard was approved by Building Material Product Standards Committee on behalfof the Standards Council of Singapore on 15 September 2001.

First published, 1989First revision, 2001

The Building Materials Product Standards Committee appointed by the Standards Council consists ofthe following members:

Name Organisation

Chairman : Mr Goh Chong Chia Standards CouncilDeputyChairman : Dr Tam Chat Tim Individual Capacity

Secretary : Mr Han Kin Sew Singapore Productivity and Standards Board

Members : Mr Boo Geok Kwang Singapore Civil Defence ForceAssoc Prof Chiew Sing Ping Nanyang Technological UniversityMr Fang Yea Saen PWD Consultants Pte LtdEr. Goh Soo Meng Institution of Engineers SingaporeMr John Kong Wai Meng Singapore Confederation of IndustriesMr Lee Seng Kee Singapore Mass Rapid TransitMr Larry Ng Lye Hock Housing & Development BoardMr Ong Geok Soo JTC CorporationMs Pauline Sim Singapore Institute of ArchitectsMr P Sripathy Land Transport AuthorityMs Tan Chiew Wan Singapore Productivity and Standards BoardAssoc Prof Tan Kiang Hwee National University of SingaporeMr Tan Tian Chong Building and Construction AuthorityMr Teo Tit Ngee Singapore Contractors Association Limited

The Technical Committee on Doors, Windows and Claddings (including Glazing) appointed by theBuilding Materials Product Standards Committee and responsible for the preparation of this standardconsists of representatives from the following organisations:

Name Organisation

Chairman : Mr Larry Ng Lye Hock Housing & Development BoardDeputyChairman : Mr See Sing Kok Institution of Engineers Singapore

Secretary : Mr Mohd Awi Singapore Productivity and Standards Board

Members : Mr Chew Kum Chong Individual CapacityMr Joseph Chng Singapore Productivity and Standards BoardMr Chua Kang Tor Singapore Productivity and Standards BoardMr Gan Geok Chua Singapore Glass Merchants and Glaziers

AssociationAssoc Prof James D Harrison National University of SingaporeMr Jee Yoke Choon Singapore Civil Defence Force


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Members : Mr Lau Kwong Chung Singapore Institute of ArchitectsMr Liew Choon Min Singapore Contractors Association LimitedMs Phua Hui Chun Building and Construction AuthorityMr See Sing Mun Individual CapacityMr Tan Kay Tho Singapore Confederation of IndustriesAssoc Prof Tan Teng Hooi Nanyang Technological University

The Working Group appointed by the Technical Committee to assist in the preparation of this standardcomprises the following members:

Name Organisation

Convenor : Mr Gan Geok Chua Individual Capacity

Members : Mr Chua Kang Tor Singapore Productivity and Standards BoardMr Han Jee Juan Individual CapacityAssoc Prof James D Harrison National University of SingaporeMr Kwan Lian Sian Singapore Civil Defence ForceMr Lim Chuin Yong Individual CapacityMr Look Boon Gee Individual CapacityMr Mau Kam Foh Housing & Development BoardMr Ong Hong Kee PWD Corporation Pte Ltd


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(blank page)


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Contents

Page

Foreword 7

SPECIFICATION

1 Scope 8

2 Application 8

3 Definitions 8

4 Requirements common to all safety glazing materials 10

5 Test requirements 14

ANNEXES

A Impact test 18

B Fragmentation test 25

C Boil test 27

D Weathering test 29

E Ageing test 32

F Determination of thickness 34

G Notes on safe performance criteria and human dynamics data 36

H Measurement of surface compression reading (non-destructive test) 38

TABLES

1.1 Thickness limits for standard nominal thickness of glass 12

1.2 Thickness limits for standard nominal imperial thickness of glass 13

2 Size tolerance for all safety glass 14

3 Flatness limits for glass of standard nominal thickness 14

4.1 Testing for safety glazing materials 15

4.2 Classification of glazing material according to behaviour when subjected toimpact test 16

4.3 Fragmentation test – Minimum particle count 16

4.4 Surface compressive stress reading 17


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Page

FIGURES

1 Test frame 21

2 Shot bag 22

3 Section A-A of test frame 23

4 Pointed protrusions 24

5 Areas to be excluded in particle count determination 26

6 Human dynamics data chart 37

7 Apparatus for measuring surface stress 39

8 Fringes observed in the plane of the compensator 40

9 Orientation of the instrument for measuring surface stress 41


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Foreword

This Singapore Standard was prepared by the Technical Committee on Doors, Windows and Cladding(including Glazing) under the direction of the Building Materials Product Standards Committee. It is arevision of SS 341 : 1989 and is largely based on Australian Standards AS/NZS 2208 : 1996 – Safetyglazing materials in buildings.

This standard covers tests to be carried out for the different types of safety glazing material such astoughened (also known as ‘fully tempered’ or ‘heat treated’), laminated, heat-strengthened, heat-strengthened laminated, liquid laminated, safety wired, organic-coated, plastic and wired glass.

This edition incorporates the following major changes from the previous edition:

(a) Introduction of the non-destructive test to measure the surface stress in heat-strengthenedand toughened glass (also known as ‘fully tempered glass’ or ‘heat treated glass’).

(b) Additional impact levels have been added to the impact test.

In preparing this standard, references were made to the following publications :

1. ASTM C 1036-1997 Standard specification for flat glass

2. ASTM C 1048-1997 Standard specification for heat-treated flat glass – Kind HS, Kind FTcoated and uncoated glass

Acknowledgement is made for the use of these publications.

Portions of this standard have been reprinted, with permission, from ASTM C 1279-94 : ‘Standard testmethod for non-destructive photoelastic measurement of edge and surface stresses in annealed, heat-strengthened, and fully tempered flat glass’ copyright American Society for Testing and Materials, 100Barr Harbor Drive, West Conshohocken, PAQ 19428. A copy of ASTM C 1279-94 may be purchasedfrom ASTM, phone 610-832-9585 fax: 610-832-9555, e-mail: [email protected], website:www.astm.org

Parts or extracts of other overseas standards incorporated into this Singapore Standard are indicatedbelow :

Table 1.1, Table 2, Table 3, Table 4.2, Table 4.3, Annex A, Annex B, Annex C, Annex D, Annex E,Annex F, Figure 1, Figure 2, Figure 3, Figure 4, Figure 5 and Figure 6 of SS 341 : 2001 are similar toTable 2.1, Table 2.2, Table 2.3, Table 3.2, Table 3.3, Figure B1, Figure D1, Figure D2, Figure D3,Figure E1, Appendix D, Appendix E, Appendix F, Appendix G, Appendix H, Appendix C and AppendixB respectively of AS/NZS 2208 : 1996 and are reproduced with the permission of Standards Australiaand Standards New Zealand.

NOTE

1. Singapore Standards are subject to periodic review to keep abreast of technological changes and newtechnical developments. The revisions of Singapore Standards are announced through the issue ofeither amendment slips or revised editions.

2. Compliance with a Singapore Standard does not exempt users from legal obligations.


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Specification for safety glazing materials for use in buildings(human impact considerations)

1 Scope

This specification sets out performance requirements and test methods for safety glazing materials foruse in buildings in areas where human impact is likely. The materials specified are glazing panelsdesigned to promote safety and to reduce or minimize the likelihood of cutting and piercing injuriesfrom human impact.

Clear, tinted and patterned safety glazing materials, and opaque glazing materials used as spandrelpanels in locations subject to human impact are included in this specification.

Glazing materials such as sealants and beads and added precautions that may be necessary tocombat fire hazards are not covered within the scope of this standard.

NOTE – Notes on safe performance criteria and human dynamics data are given in Annex G.

2 Application

The safety glazing materials shall comply with the relevant requirements of Clauses 4 and 5.

NOTE – This specification is not intended to restrict the use of materials or methods of test not specified hereinwhere such materials or methods of test can be demonstrated to be equal or superior to those specified. TheRegulatory Authority must always make the ultimate decision as to whether or not a material or method of testmay be used.

3 Definitions

For the purpose of this specification the following definitions shall apply:

3.1 Drop height

The vertical distance from the horizontal centre-line of the maximum diameter of the impacting objectwhen it is released relative to the horizontal centre-line of the impacting object when it is at rest (seeFigure 1).

3.2 Heat-strengthened glass

Glass which has been subjected to a special heat treatment, so that the residual surface compressionstresses lies between 28 MPa and 48 MPa.

3.3 Heat-strengthened laminated safety glass

Laminated safety glass utilizing two or more panels of heat-strengthened glass in the make-up.


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3.4 Laminated safety glass

A glass consisting of two or more sheets of glass bonded together either by one or more sheets ofplastic interlayer or permanently bonded together by liquid chemicals that cure to form a plastic-typeinterlayer.

3.5 Liquid-laminated safety glass

A glass consisting of two or more sheets of glass permanently bonded together by liquid chemicalsthat cure to from a plastic-type interlayer.

3.6 Regulatory authority

Authority that is responsible for preparing or adopting regulations.

3.7 Safety double (or multiple) glazing unit

A double (or multiple) glazing unit in which all panels are of safety glazing material and are separatedby airspaces.

3.8 Safety glazing materials

Materials so constructed, treated or combined with other materials as to reduce the likelihood ofcutting and piercing injuries resulting from human impact with them. All safety glazing materials areclassified as either Grade A or B according to the performance requirements in Clause 5.

3.9 Safety organic-backed mirror

A glazing material consisting of a piece of mirror with a sheet of organic material permanently bondedto one side, and which complies with the relevant test requirements of this specification.

3.10 Safety organic-coated glass

A glazing material consisting of a piece of glass coated and permanently bonded on one or both sideswith a continuous polymeric coating, sheet or film.

3.11 Safety plastic glazing material

A glazing material which contains as an essential ingredient, an organic substance of large molecularmass, is solid in its finished state, and at some stage in its manufacture or in its processing intofinished articles can be shaped by flow. Plastic may consist of a single sheet of synthetic plasticsmaterial, a combination of two or more such sheets laminated together, or a combination of plasticsmaterial and reinforcement material in the form of fibres or flakes, and which complies with therelevant test requirements of this specification.

3.12 Safety wired glass

A single sheet of glass with wire completely embedded in the glass.

3.13 Toughened laminated safety glass

Laminated safety glass utilizing two panels of fully tempered safety glass in the make-up.

NOTE – Toughened glass is also known as ‘fully tempered glass’ or ‘heat treated glass’


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3.14 Toughened safety glass

A glass which has been converted to a safety glass by subjection to a process of prestressing so that,if fractured, the entire piece disintegrates into small relatively harmless particles.

NOTE 1 – In general, the heat treatment or chemical process greatly reduces the tendency of glass fractureunder the action of external forces and changes of temperature.

NOTE 2 – After being tempered the glass cannot be cut, drilled, ground or otherwise reworked. Etched,sandblasted, engraved or otherwise worked surfaces should have such surface working carried out prior totempering. Surface treatments should be kept as shallow as possible to ensure that the glass can be adequatelytempered.

NOTE 3 – Toughened glass is also known as ‘fully tempered glass’ or ‘heat treated glass’

4 Requirements common to all safety glazing materials

4.1 General

Safety glazing materials, which may be transparent, translucent or opaque, as required, shall becapable of satisfactorily functioning in the service for which they are intended. It shall be free fromdefects, e.g. cracks, scratches, blisters or inclusions of magnitude that could impair performance, forexample in use.

4.2 Testing

Testing shall be carried out to ensure compliance of safety glazing materials with this specification.Separate testing shall be carried out for different glazing materials, or for differences within a type ofglazing material that could noticeably affect performance in the impact, fragmentation or environmentaldurability tests. Such differences may include, but are not limited to, nominal thickness or thicknesses,method of manufacture, types and amounts of additives, and composition of base materials andadhesives.

Alternative methods for determining compliance with this standard can be demonstrated by themanufacturer or supplier by one of the following methods:

(a) Evaluation by means of statistical sampling in accordance with ISO 2859;

(b) The use of product certification scheme as described in ISO/IEC Guide 28;

(c) Assurance using the acceptability of the manufacturer’s quality system. Guidance indetermining the appropriate quality system is given in SS ISO 9000-1 and SS ISO 9004-1.

If the above methods are considered inappropriate, determination of compliance with the requirementsof this standard may be assessed by being based on the results of testing coupled with themanufacturer’s guarantee of product conformance.

4.3 Classification

All safety glazing materials shall be classified as either Grade A or Grade B according to theperformance requirements in Clause 5.


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4.4 Marking

Glazing material complying with this standard shall be legibly marked with the following:

(a) The name or registered trademark of the manufacturer or supplier;

(b) The number of this Singapore Standard, SS 341;

(c) A letter or other code to indicate plant of manufacture or supply;

(d) Grade A or Grade B to indicate the grade of the material;

(e) A number to indicate the nominal thickness for standard glazing material in millimetres, or anumber to indicate the minimum thickness for non-standard glazing material to the nearesttenth of a millimetre;

(f) A letter or word or combinations thereof to indicate the type of glazing material used in theproduct.

4.5 Standard nominal thickness of glass

Limits on the standard nominal thickness of various types of glass are given in Table 1.1. Thethickness of the glass shall be measured in accordance with Annex F

4.6 Standard nominal imperial thickness of glass

Limits on the standard nominal thickness of glass manufactured to imperial sizes are given in Table1.2. The thickness of the glass shall be measured in accordance with Annex F

4.7 Non-standard thickness of glass

Thicknesses of safety glass other than those specified in Table 1.1 and Table 1.2 may be utilized andshall not be a cause for rejection provided that the product meets all other appropriate testrequirements of this standard.

4.8 Squareness of rectangular panels

The squareness of rectangular panels shall be such that the difference between the two diagonalsdoes not exceed 5 mm for panels where the largest dimension is less than 1200 mm and 10 mm for allother panels.

4.9 Size tolerances

The tolerances on size of all safety glass shall be as specified in Table 2.

4.10 Flatness

The flatness of panels shall be within the following limits:

(a) Localized warp 1.0 mm over any 200 mm span;

(b) Overall bow and warpage as given in Table 3.

NOTE – Flatness measurement shall be checked against a straightedge with the panel standing within 5° ofvertical and measurement taken horizontally.


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4.11 Edgework

Prior to heat treatment, glass shall be arrised on all edges.

NOTE 1 – Arrised edges are formed by grinding a chamfer or bevel of approximately 1 mm wide on all sharpedges and corners.

NOTE 2 – Care should be exercized when handling glass to prevent edge damage and subsequent fracture.Toughened safety glass cannot be cut, drilled, ground or otherwise reworked. Particular care is required whenhandling toughened (‘fully tempered’ or ‘heat treated’) safety glass as damaged edges may result inspontaneous glass fracture.

Table 1.1 – Thickness limits for standard nominal thicknesses of glass

millimetresStandard nominal Glass thickness limits

Type of glass thickness Minimum Maximum

3 2.8 3.24 3.8 4.25 4.8 5.26 5.8 6.2

Toughened glass, and 8 7.7 8.3heat- strengthened glass 10 9.7 10.3

12 11.7 12.315 14.5 15.519 18.0 20.025 23.5 26.5

5.38 4.6 5.46.38 5.6 6.4

Laminated glass 8.38 7.6 8.410.38 9.6 10.412.38 11.6 12.416.38 15.4 16.6

6.38 5.6 6.4Toughened laminated glass, 8.38 7.6 8.4and heat-strengthenedLaminated glass 10.38 9.3 10.4

12.38 11.3 12.4

Patterned glass, 3 2.5 3.9Toughened patterned 4 3.5 4.5glass, and heat 5 4.5 5.5Strengthened patterned 6 5.5 7.0Glass 10 9.0 10.8

12 11.0 13.5

Wired glass 6 5.0 6.8

NOTES:

1. For glass that does not satisfy the thickness tolerances for the standard nominal thickness specified above,the minimum glass thickness shall be marked.

2. Linear interpolation shall apply for non-standard thickness.3. Glass thickness limits specified for laminated glass exclude interlayer thickness.4. Toughened glass is also known as ‘fully tempered glass’ or ‘heat treated glass’


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Table 1.2 – Thickness limits for standard nominal imperial thicknesses of glass

inchesNominal imperial Glass thickness limits

Type of glass thickness minimum maximum

1⁄8 0.115(2.92) 0.134(3.40)5⁄32 0.149(3.78) 0.165(4.19)3⁄16 0.180(4.57) 0.199(5.05)

7⁄32 0.200(5.08) 0.218(5.54)¼ 0.219(5.56) 0.244(6.20)

5⁄16 0.292(7.42) 0.332(8.43)

Toughened and 3⁄8 0.355(9.02) 0.406(10.31)Heat-strengthened ½ 0.469(11.91) 0.531(13.49)

glass 5⁄8 0.595(14.35) 0.656(16.66)

¾ 0.719(18.26) 0.781(19.84)7⁄8 0.844(21.44) 0.906(23.01)1 0.969(24.61) 1.031(26.19)

1¼ 1.125(28.58) 1.375(34.93)

3⁄16 0.186(4.72) 0.218(5.54)¼ 0.230(5.84) 0.268(6.81)

5⁄16 0.298(7.57) 0.330(8.38)Laminated glass 3⁄8 0.360(9.14) 0.398(10.11)

½ 0.438(11.13) 0.488(12.40)5⁄8 0.584(14.83) 0.664(16.87)

NOTES:

1. For glass that does not satisfy the thickness tolerances for the standard nominal thickness specified above,the minimum glass thickness shall be marked.

2. Linear interpolation shall apply for non-standard thickness.3. Glass thickness limits specified for laminated glass exclude interlayer thickness.4. Toughened glass is also known as ‘fully tempered glass’ or ‘heat treated glass’.5. The values given in bracket are in millimetres.


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Table 2 – Size tolerance for all safety glass

millimetresStandard Tolerance limitsNominal Non-patterned Patterned

Thickness < 1200 ≥ 1200 < 1200 ≥ 1200

3 ± 2 ± 2 ± 3 ± 44 ± 2 ± 2 ± 3 ± 45 ± 2 ± 2 ± 3 ± 4

6 ± 2 ± 2 ± 3 ± 48 ± 2 ± 2 ± 4 ± 5

10 ± 2 ± 3 ± 4 ± 5

12 ± 2 ± 3 ± 4 ± 515 ± 2 ± 3 19 ± 2 ± 3

25 ± 2 ± 3

NOTE – For non-standard glass thickness, interpolation will be required.

Table 3 – Flatness limits for glass of standard nominal thickness

millimetresStandard nominal Bow

Thickness 0 to 1500 1501 to 3000 3001 to 5000

3 1 in 200 1 in 150 4 1 in 200 1 in 150 5 1 in 300 1 in 200 1 in 200

6 1 in 350 1 in 250 1 in 2008 1 in 400 1 in 300 1 in 25010 1 in 400 1 in 300 1 in 250

12 1 in 400 1 in 300 1 in 25015 1 in 400 1 in 300 1 in 25019 1 in 400 1 in 300 1 in 250

25 1 in 400 1 in 300 1 in 250

NOTE – For non-standard glass thickness, interpolation will be required.

5 Test requirements

5.1 General

Glazing materials shall be classified as Grade A or Grade B safety glazing material if it is shown thatthey satisfy the relevant impact (or fragmentation test for toughened glass) test performancerequirements in addition to all other appropriate tests to be carried out as listed in Table 4.1


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Table 4.1 – Testing for safety glazing materials

Glazing type

Heat- Safety Organic- Safety Organic-Laminated

safetyglass

Toughenedsafetyglass*

strengthenedand

toughened

wiredglass

coatedsafetyglass

plastics backedsafetymirror

laminatedsafety glass

Test

Impact X X X X X X X(see 5.2)

Fragmentation X (see 5.3)

Surfacecompression

X

measurement(see 5.4)

Boil X X (see 5.5)

Weathering X X (see 5.6)

Ageing X X(see 5.7)

X indicates test to be conducted* For toughened safety glass an impact, fragmentation test or surface compression

measurement shall be carried out. Toughened glass is also known as ‘fully tempered glass’or ‘heat treated glass’

NOTE – Boil test for heat-strengthened and toughened laminated glass can use laminates from ordinaryannealed glass manufactured simultaneously.

5.2 Impact test

5.2.1 Test specimens

Test specimens shall be prepared in a manner representative of normal installation practice. Forexample, if a safety organic-coated glass is used, the coating shall be applied to the test specimen in amanner that is representative of normal application (normally confined within the visible sight linesonly).

5.2.2 Orientation of test specimens

For a symmetric material (any material symmetric about the geometric centre plane through itsthickness, including fully tempered glass and some laminated glass) the impact test shall be carriedout by impacting on either face.


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For an asymmetric material (any material not symmetric about the geometric centre plane through itsthickness, including patterned wired, organic coated glass and laminated glass with mixed glass typesor thicknesses) the classification shall be based on impact test results for impact on the face that isshown to give the worst performance.

5.2.3 Testing and classification

Grade A glazing material tested in accordance with Annex A (see also Table 4.2), at a drop height of300 mm, shall not break or shall comply with the requirements for breakage given in Annex A. Ifbreakage does not occur at 300 mm, then the drop height is progressively increased to 450 mm, 600mm, 750 mm, 900 mm, 1200 mm and 1500 mm until breakage occurs. When breakage occurs itshall comply with the requirements for breakage as given in Annex A.

Grade B glazing material, when tested in accordance with Annex A (see also Table 4.2), at a dropheight of 200 mm, shall not break or shall comply with the requirements for breakage given in AnnexA. If breakage does not occur at 200 mm, then the drop height is progressively increased to 300 mm,450 mm, 600 mm, 750 mm, 900 mm, 1200 mm and 1500 mm until breakage occurs. When breakageoccurs it shall comply with the requirements for breakage given in Annex A.

Table 4.2 – Classification of glazing material according to behaviour whensubjected to the impact test

Class Drop height 200 mm nominal Drop height 300 mm to1500 mm nominal

Drop height greater than1500 mm or bya centre punch

A No requirement No breakage, or Breaks safely or

breaks safely deforms

B No breakage, or No breakage, or No requirement

breaks safely breaks safely

5.3 Fragmentation test

When samples of safety glazing are tested in accordance with Annex B, a sample which complies withthe minimum particle count specified in Table 4.3 shall be deemed to comply with the requirements forGrade A safety glazing materials specified in 5.2.

Table 4.3 – Fragmentation test – Minimum particle count

Nominal glazing material Minimum number of particlesthickness (mm) per square of 50 mm side

3 30

4 30

5 40

6 40

8 40

10 40

12 40

NOTE – There is no reference to particle count for 15 mm, 19mm and 25 mm due to lack of scientific data.


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5.4 Surface compression measurement (non-destructive testing)

When samples are tested in accordance with Annex H, the surface compressive stress reading shallmeet the requirements given in Table 4.4.

Table 4.4 – Surface compressive stress reading

Minimum surface compressivestress readingClassification of toughened glass

Psi MPa

8 mm and below 11,500 79

Above 8 mm 10,000 69

NOTE – Toughened glass is also known as ‘fully tempered glass’ or ‘heat treated glass’

5.5 Boil test

When tested in accordance with Annex C, the glazing material itself might crack, but no bubbles orother defects shall develop more than 12 mm from the edge of the test specimen or from any cracksthat have developed.

Any test specimen which cracks to an extent that the results are confused, shall be discarded withoutprejudice and another specimen shall be tested in its stead.

5.6 Weathering test

5.6.1 Safety organic-coated glass

Safety organic-coated glass, when tested in accordance with Annex D, shall have:

(a) an average adhesion value, when exposed to weathering, of not less than 90 per cent of theaverage adhesion value not exposed to weathering; and

(b) an average tensile strength, when exposed to weathering, of not less than 75 per cent of theaverage tensile strength not exposed to weathering.

5.6.2 Safety plastics

Safety plastics glazing materials intended for use in all applications when tested in accordance toAnnex D shall have the impact resistance when exposed to weathering of not less than 75 percent ofthe impact strength when not exposed to weathering. When exposed to weathering, the safetyplastics glazing material may show some discolouration, but no bubbles or noticeable decompositionshall develop in the irradiated portion.

In addition, for safety plastics the modulus of elasticity shall not be less than 5170 Mpa and a Rockwellhardness shall not be less than M140 or R140.

5.7 Ageing test

Safety glazing materials intended for use in all applications after ageing in accordance with Annex Eshall comply with the requirements for Grade A safety glazing materials in 5.2.

After ageing, some discolouration or milkiness may develop and is allowable but defects other thanthese shall not be permitted.


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Annex A

Impact test

A.1 Scope

This annex sets out the method for determining the resistance of glazing material to impact by thepenetration method.

A.2 Principle

The specimen is supported vertically in a steel frame and an impact shot bag is released from a pre-determined height to strike the specimen at the centre. The height is progressively increased untilfracture occurs.

A.3 Apparatus

The following apparatus is required:

(a) A steel frame to support the sample in a vertical plane. The frame is to be securely bolted tothe floor and have edge clamps to hold the glazing material in position (see Figure 1).

(b) An impacting shot bag as shown in Figure 2. The impacting shot bag is a reinforced leatherbag filled with No. 7½ chilled lead shot, providing a total mass of 46 ± 0.1 kg. The bag isconstructed either of 1.6 mm thick pliable leather with canvas laminated to the inside surfacemaking a wall thickness of 2.4 mm, or of thick pliable vinyl. A rubber bladder of 0.6 mm wallthickness is contained within the leather or vinyl outer shell and is filled with lead shot througha small hole in the upper portion. After filling, the rubber bladder is closed by tying with a cordor leather thong.

NOTE – Commercial punching bags meeting this specification may be available.

A method for attaching the shot bag to the test frame and for swinging the test bag from the heightrequired needs to be devised.

A.4 Samples and sample preparation

A.4.1 Sampling

A minimum of four test specimens shall be tested.

A.4.2 Specimen size

Each specimen shall be 1900 mm ± 3 mm high by 860 mm ± 3 mm wide, or the maximum sizeavailable if that is smaller.

A.4.3 Conditioning

Immediately prior to testing specimens shall be conditioned for a minimum of 4 h at a temperature of23 ± 5°C with the test surfaces exposed to full air at that temperature. Toughened glass does notrequire conditioning.


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A.5 Procedure

The procedure shall be as follows:

(a) Place the test specimen in the frame.

(b) Suspend the impacting shot bag from an overhead support so located that the impactingobject when at rest will, at its maximum diameter, be not more than 12 mm from the surface ofthe test specimen and not more than 50 mm from the centre of the specimen (see Figure 1).

(c) Raise the shot bag by the bridle to a drop height of 300 mm for Grade A or 200 mm for GradeB safety glazing.

(d) Stabilize the shot bag before release.

(e) Release the shot bag, allowing it to swing smoothly through a pendulum arc and strike thespecimen once at the centre.

(f) In the event of the test specimen coming out of the frame, disregard the sample.

(g) Inspect the test specimen and determine if it complies with any of the following requirementsafter impact and record:

(i) it has remained unbroken; or

(ii) it has broken and numerous cracks or fissures appear but no shear or openingdevelops within the body of the glazing material through which a 76 mm diametersphere can be passed freely; additionally, if fragments are detached from the testpiece up to 3 min after impact, they shall, in total, weigh no more than the massequivalent to 10 000 mm2 of the original test piece and the largest single fragmentshall weigh less than the mass equivalent to 4400 mm2 of the original test piece; or

(iii) it has broken and disintegration occurs but the 10 largest crack-free fragments selected3 min after impact, together weigh no more than the mass equivalent to 6500 mm² ofthe original test piece; or

(iv) it has broken and the breakage results in several separate pieces, which may or maynot be retained in the frame. Those pieces that are exposed after the impact shall bein accordance with one or both of the following:

(A) The perimeter shall not be sharp.

(B) Where any pointed protrusion occurs in any perimeter, the length of the chordbetween the two points which are established when an arc of radius 25 mm,whose centre is at the apex of the protrusion, crosses the perimeter on eachside of the apex shall not be less 25 mm. (see Figure 4).

(h) If any one of the test specimens which break do not comply with the requirements of Step (g),terminate the procedure, the product has failed.

(i) If the test specimen does not break and remains intact within the frame, progressivelyincrease the drop height as follows:

Grade A : 450 mm, 600 mm, 750 mm, 900 mm, 1200 mm and 1500 mm.

Grade B : 300 mm, 450 mm, 600 mm, 750 mm, 900 mm, 1200 mm and 1500 mm.


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(j) Inspect the test specimen in accordance with Step (g) for each drop height.

Interpretation: In the event of the glazing material not breaking after being impacted from adrop height of 1500 mm, use a centre-punch with sufficient force to deform or break theglazing material and examine the fracture pattern as follows:

(i) If the glazing material disintegrates into small fragments as defined in Step (g)above, it is considered a pass.

(ii) If the panel cracks or deforms but is held together in a safe manner, it passes.

(iii) If it breaks in large pieces and can be pushed out of the frame, it fails.

(k) Repeat Steps (a) to (h) for the other three specimens.

A.6 Report

The following information shall be reported:

(a) Identification of the test specimen.

(b) For each drop height, whether the test specimen remained unbroken. If not, whether it brokeand complied with the requirements of Paragraph A.5 (g)(ii) to (iv), or broke and did notcomply with the requirements of A.5 (g)(ii) to (iv).

(c) Grade of pass or fail.

(d) Location of testing facility.

(e) Date and time of the test.

(f) Names, position and relevant qualifications of personnel carrying out or supervising the test.

(g) Names, positions and relevant qualifications of witnesses, if any, to the test.

Each page of the report shall be signed and dated by the person responsible for the test.


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Fi

gure

1 –

Tes

t fra

me


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Figure 2 – Shot bag


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Figure 3 – Section A-A of test frame


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Figure 4 – Pointed protrusions


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Annex B

Fragmentation test

B.1 Scope

This annex sets out the method for determining the fracture characteristics of toughened safety glassor other glazing materials.

B.2 Apparatus


(a) A flat wooden platform, if floor is unsuitable (see Paragraph B.5 (a)).

(b) A spring-loaded carbide tipped centre-punch or similar manual-type centre-punch.

B.3 Principle

The specimen is laid horizontally on a surface that supports it over its entire area, and is broken by apunch applied at a predetermined location. The number of particles of broken glazing material within agiven area are counted.

B.4 Samples

Each specimen shall be taken from the production run.

B.5 Procedure


(a) Place the specimen horizontally upon a flat wooden platform or floor that will support the testspecimen on its entire surface. Provide a means to prevent any substantial spreading of thefragments.

(b) Break the test specimen by means of a spring-loaded carbide tipped centre-punch, or similarmanual-typed centre-punch struck with a hammer. The punch blow shall be applied 13 mminboard from and at the midpoint of the longest edge of the specimen.

(c) Make a count of the particles of broken glazing material within 5 min of the fracture of theglazing material. The particle count shall be made in the region of the coarsest fracture,excluding a segment of radius 75 mm centred on the point of impact of the centre-punch andtwo further segments (S) of radius 75 mm centred as shown in Figure 5. The particle countshall be made in a square of side 50 mm. In the particle count, all particles wholly containedwithin the square and all the particles only partially contained by two adjacent edges of thesquare shall be counted. All particles only partially contained by the other two adjacent edgesof the square shall not be counted. Only particles containing both original faces shall becounted.


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Figure 5 – Areas to be excluded in particle count determination

B.6 Test report



(b) Particle count of the fractured test specimen.

(c) Location of testing facility.

(d) Date and time of the test.

(e) Names, position and relevant qualifications of personnel carrying out or supervising the test.

(f) Names, positions and relevant qualifications of witnesses, if any, to the test.



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Annex C

Boil test

C.1 Scope

This annex sets out the method for determining the effect of exposure of safety glazing material totemperature and humidity conditions by boiling.

C.2 Principle

Specimens are immersed in hot water and then boiling water for a specified period of time andinspected for bubbles or other defects.

C.3 Apparatus

The apparatus shall be two water baths each of sufficient size to hold the test specimen fullyimmersed vertically on edge, for the duration of test.

C.4 Samples

Three specimens of size 300 mm x 300 mm manufactured in a manner identical with the impact testspecimens (see Annex A) and of like thickness shall be tested. These specimens may be cut from theproduction samples of the size and thickness submitted for impact testing. For heat strengthened orfully tempered laminated glass, test specimens may be cut from a similar original sheet of annealedlaminated glass.

C.5 Procedure


(a) Immerse the specimens vertically on edge in a bath of water maintained at a temperature of66 ± 3°C for 3 min.

(b) Quickly transfer the specimens to a bath of water maintained at boiling point. Immerse thespecimens vertically on edge in the bath for 2 h.

(c) Remove the specimens and examine for bubbles or other defects.

C.6 Test report



(b) Position of cracks.

(c) Number, size and location of bubbles in relation to the outer edge of the test specimen and toany cracks.


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(d) Temperature of water in baths.

(e) Location of testing facility.

(f) Date and time of test.

(g) Names, position and relevant qualifications of personnel carrying out or supervising the test.

(h) Names, positions and relevant qualifications of witnesses, if any, to the test.



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Annex D

Weathering test

D.1 Scope

This annex sets out the method for determining the effect of radiant exposure on safety glazingmaterials.

D.2 Principle

Specimens are exposed, under specified conditions, to light from an artificial light source. Afterexposure, safety plastics are then subject to the Charpy impact test. Organic-coated glass issubjected to a tensile test and an adhesion test. The effect of radiant exposure is assessed bycomparing the test results of exposed specimens with those of unexposed specimens.

D.3 Apparatus


(a) Apparatus specified in ASTM G26.

(b) Apparatus specified in ASTM D756.

(c) A constant-rate-of-extension tensile testing machine complying with the requirements for aGrade B machine in accordance with AS 2193. The moving crosshead shall be able to be setto move at 50 mm/min and 300 mm/min.

(d) Razor cutter.

D.4 Sample and sample preparation

D.4.1 Sampling

A minimum of 20 test specimens shall be sampled.

D.4.2 Size of specimen

The size of specimens shall be 150 mm long by 50 mm wide.

D.4.3 Conditioning

The organic-coated glass specimens shall be conditioned for 24 h in darkness at a temperature of 23± 2°C and a relative humidity of 55 ± 5 percent.


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D.5 Procedure

D.5.1 General

Ten specimens shall be the controls (unexposed specimens). For organic-coated glass they shall besubjected to adhesion and tensile tests. For safety plastics they shall be subjected to a Charpyimpact test.

The other 10 specimens (exposed specimens) shall be subjected to the weathering test and thensubject to the adhesion and tensile test for organic-coated glass and to the Charpy impact test forsafety plastics.

D.5.2 Unexposed specimens

D.5.2.1 Adhesion test


(a) Take ten specimens.

(b) Set up the tensile testing machine with the crosshead rate at 300 mm/min and the force rangeof the machine so that the peel occurs between 10 percent and 90 percent of full-scale force.

(c) Using a razor cutter, cut a 25 mm wide strip of the organic coating in the lengthwise directionof the glazing material sample. Peel back about 50 mm of the 25 mm wide strip.

(d) Attach a strip of pressure-sensitive tape to the side of the organic strip opposite the adhesiveto extend this free end to about 200 mm in length.

(e) Place the end of the glazing material panel from which the organic strip was removed in thelower clamp of the tensile tester and the free end of the tape in the upper clamp. Peel theremainder of the organic strip from the glazing material mechanically and obtain a record ofthe peel value.

D.5.2.2 Tensile test


(a) Take the ten specimens used in the adhesion test (see D.5.2.1).

(b) Set up the tensile testing machine with the crosshead rate at 50 mm/min, the gauge length at50 ± 2 mm and the load range so that the specimens will break at approximately midscaledeflection.

(c) Using a razor cutter, cut a 12 mm straight strip of the organic coating in the lengthwisedirection of the glazing material sample for the full 150 mm length.

(d) Carefully peel this strip from the glazing material panel and break it in the testing machine andrecord the pull-at-breakage for each specimen.

D.5.2.3 Impact

Subject ten specimens to the Charpy unnotched impact test in accordance with ASTM D756.


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D.5.3 Exposed specimens

The procedures shall be as follows:

(a) Subject ten specimens to radiant exposure of 500 MW.s in accordance with ASTM D1499.

(b) For organic-coated glass determine the peel value and pull-at-breakage in accordance withD.5.2.1 and D.5.2.2 respectively.

(c) For safety plastic, subject the ten specimens to the Charpy unnotched impact test inaccordance with ASTM D756, with the exposed surface subject to tension. For thin materials,the span of the specimen shall be reduced to 50 mm to avoid having the specimen bendenough to slip between the supports without breaking.

D.6 Test report


(a) Identification of the test specimens.

(b) Test report requirements of ASTM D756 and ASTM D1499.

(c) For organic-coated glass, the peel value determined from the adhesion test and the pull atbreakage determined from the tensile test for both unexposed and exposed specimens.

(d) Location of testing facility.

(e) Date and time of the test.

(f) Names, positions and relevant qualifications of personnel carrying out or supervising the test.

(g) Names, positions and relevant qualifications of witnesses, if any, to the test.



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Annex E

Ageing test

E.1 Scope

This annex sets out the method for determining the effect of accelerated ageing on safety glazingmaterials.

E.2 Principle

Specimens are exposed under specified conditions to warm, humid and dry cycles and then subject toan impact test (see Annex A). The effect of accelerated ageing is assessed by comparing the impacttest results of exposed specimens, with those of unexposed specimens.

E.3 Apparatus


(a) Apparatus specified in DIN 50 017.

(b) Apparatus specified in Annex A.

E.4 Sample and sample preparation

E.4.1 Sampling

A minimum of eight test specimens shall be sampled.

E.4.2 Size of specimen

The size of specimens shall be in accordance with Annex A.

E.5 Procedure

E.5.1 Unexposed specimens


(a) Take four specimens.

(b) Determine the resistance to impact of each specimen in accordance with Annex A.

E.5.2 Exposed specimens


(a) Take four specimens.


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(b) Subject each specimen to 20 complete humid/dry test cycles of 480 h in accordance with DIN50017.

(c) Determine the resistance to impact of each specimen in accordance with Annex A.

E.6 Test report


(a) Identification of the test specimens.

(b) Drop height at which breakage of the test specimen occurs for both unexposed and exposedspecimens.

(c) Location of testing facility.

(d) Date and time of the test.

(e) Names, positions and relevant qualifications of personnel carrying out or supervising the test.

(f) Names, positions and relevant qualifications of witnesses, if any, to the test.



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Annex F

Determination of thickness

F.1 Scope

This annex sets out the method for determining the thickness of a glazing material.

F.2 Principle

The glazing material is measured at specified locations with a vernier calliper or micrometer (patternedglass is also measured using a point micrometer).

F.3 Apparatus


(a) For flat glazing material a vernier calliper or micrometer graduated to 0.01 mm.

(b) For patterned glazing material:

(i) a point micrometer graduated to 0.01 mm; and

(ii) a 55 mm anvil micrometer or flanged dial indicator graduated to 0.01 mm.

F.4 Procedure

The procedure for flat glazing material shall be to measure the thickness at two locationsapproximately equally spaced along each of two adjacent edges (a total of four measurements) usingeither a vernier calliper or a 55 mm anvil micrometer.

The procedure for patterned glazing material shall be to measure the thickness at two locations oneach of two adjacent edges. The locations shall be spaced at least half the respective edge lengthapart, using both a 55 mm anvil micrometer or flanged dial indicator and a point micrometer tomeasure the thickest and thinnest glass points at each location (a total of eight measurements).

F.5 Test report


(a) Identification of the glazing material.

(b) Values of the individual readings.

(c) For flat glazing material, the mean of the four readings taken.

(d) For patterned glazing material, the mean of the four readings taken of the thickest sectionsand the mean of the four readings taken of the thinnest sections.

(e) Location of testing facility.


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(f) Date and time of the test.

(g) Names, positions and relevant qualifications of personnel carrying out or supervising the test.

(h) Names, positions and relevant qualifications of witnesses, if any, to the test.


F.6 Interpretation

The interpretation shall be as follows:

(a) For flat glazing material, the mean of the measurements taken shall be within the thicknesslimits specified in Table 1.1 and 1.2 respectively.

(b) For patterned glazing material, the mean of the measurements shall be as follows:

(i) Equal to or less than the maximum thickness limit specified in Table 1.1 and 1.2respectively, for measurements taken over the thickest sections.

(ii) Equal to or greater than the minimum thickness limit specified in Table 1.1 and 1.2respectively, for measurements taken at the thinnest sections.


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Annex G

Notes on safe performance criteria andhuman dynamics data

G.1 Safe performance criteria

The performance criteria specified are directly related to the reduction of cutting and piercing injuriesto persons who impact the glazing used in buildings.

The 90 J energy level was established as being practically related to those situations where theglazing is around a confined space and there is a limited acceleration path available for the buildinguser to develop much kinetic energy.

The 135 J and 203 J energy levels were established as practically related to those situations in whichthe limited acceleration path precluded, in most cases, the possibility of an individual developing hisor her full kinetic energy potential.

The 541 J impact energy level was established for relatively unlimited acceleration paths in which itmight be reasonable to expect that an energetic teenager might develop something approaching his orher impact velocity.

As G.2 and Figure 6 indicate, independent safety experts in the USA who considered the matterjudged that these values were realistic.

G.2 Development of human dynamics data chart

Safety experts in the USA indicate that a 46 kg person is representative of glazing material breakageaccident victims. From the chart (Figure 6) it is apparent that a 46 kg person running at the rate of 6.7m/s (equivalent to a 4-minute mile) has about 134 J of kinetic energy. The amount of this energy hemight deliver to a glazed opening would depend upon the way he hit the glazed surface; a “straightarm” would transmit more energy to the glazing material than an arm which flexes with the impact.

For test purposes, ANSI* decided after extensive evaluation to use a readily available standardpunching bag filled with 46 kg of lead shot to simulate the running person. The test impact values135 J, 203 J and 541 J were selected as representative of energy levels likely to be delivered by humansin situations involving interior doors and patio doors. These test levels were set considerably belowthe 1034 J kinetic energy of the typical victim, since the impact energy delivered to the glazingmaterials perhaps first by the hands, then by the head, and then by the knees is much less than thekinetic energy of the running person. Also the incident angle of impact will be less than normal inmost cases.

In Australia and New Zealand the test impact value of 90 J was selected as representative of energylevels likely to be delivered by humans in situations involving glazing around confined spaces, e.g.shower screens.

Figure 6 was developed to assist in the establishment of performance criteria for safety glazingmaterials subject to human impact. The chart is based on the kinetic energy formula:

T = 0.5 mv²

* See ANSI Z97.1


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where:

T = kinetic energy, in joules

m = mass of missile, in kilograms

v = velocity of missile, in metres per second.

Maximum impact energy equals the kinetic energy of the person in motion at the moment of impact.Actual impact energy (that which the person delivers) will always be considerably less, except perhapsin the case of a person falling on a skylight.

Figure 6 – Human dynamics data


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Annex H

Measurement of surface compression reading(non-destructive test)

H.1 Scope

This annex covers the determination of surface compressive stresses in heat-strengthened andtoughened glass (also known as fully tempered glass).

H.2 Summary of test method

The procedure describes a test method for measuring surface stress using light propagating nearlyparallel to the surface. The fundamental photoelastic concept is used. As a result of stresses, thematerial becomes optically anisotropic or birefringent. When polarized light propagates through suchanisotropic materials, the differences in the speed of light rays vibrating along the maximum andminimum principal stress introduce a relative retardation between these rays. This relative retardationis proportional to the measured stresses, and can be accurately determined using compensators.

H.3 Principles of operation

The principles of operation are as follows:

(a) Measurement of surface stresses requires an optical apparatus that permits the injection ofpolarized light rays propagating in a thin layer adjacent to the surface (see Note 1). A prism isusually used for this purpose. The rays emerge at critical angle ic. The photoelasticretardation due to the surface stresses, (see Figure 7), is measured using a wedge-compensator.

(b) The incident light beam should be arriving at the critical angle ic and polarized at 45° to theentrance of the prism edge. A quartz wedge-compensator, Wc , placed in the path of emerginglight adds a retardation, Rc, to the retardation Rs induced by stresses in the surface of thespecimen. The analyzer, A, placed between the eyepiece, E, and the wedge-compensator,Wc, generates a visible set of fringes or lines of constant retardation R where

R = Rs + Rc

Since the specimen-induced retardation is proportional to the surface stress, S, and the path,t, we have:

Rs = C⋅S⋅t = C⋅S⋅aX (1)

where:

R = is the relative retardation,C = stress-optical constant (see Note 2),S = surface stress in the direction perpendicular to the path, tt = path of light travelling between the entrance and exit points 1, 2 (Figure 7)

a = Geometrical factor, (depending upon the prism design) X

ta = . This constant is

determined by the manufacturer.


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(c) The compensator adds its own retardation. It is linearly variable along its length y and iscalculated as

Rc = b⋅y (2)

where b is a constant, determined by the manufacturer of the compensator. The observersees in the compensator plane a total retardation R.

R = Rs + Rc = a⋅C⋅S x + b⋅y (3)

Figure 7 – Apparatus for measuring surface stress

(d) The fringes (lines of R = Constant) are, therefore, tilted lines. (See Figure 8). The angle θ isthe tilt of these fringes relative to a plane containing the light path of Figures 7 and 8. Themeasured stress is proportional to the tangent of the tilt angle θ , measured using agoniometer, and to an instrument calibration constant, K MPa (psi), determined by themanufacturer.

tan θ = b

SCa ⋅⋅and

Stress = aC

b· tan θ = K · tan θ (4)

In the actual procedure (see below), the operator measures the tilt angle θ of the observed set offringes.

NOTE 1 – The surface-stress measuring apparatus described in this annex is manufactured by StrainopticTechnologies, Inc. in North Wales, Pennsylvania.

NOTE 2 – The stress constant of float glass is typically 2.55 to 2.65 Brewsters. Calibration can be performedusing one of the test methods described in Test Methods ASTM C770.


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Figure 8 – Fringes observed in the plane of the compensator

H.4 Procedure

The procedure of measuring the surface stress is as follows:

(a) Clean the surface of any trace of oil or other chemical deposits.

(b) Place a few drops of index liquid on the tin side surface of the specimen at the point ofinterest. The index of refraction of the liquid should be higher than the index of the examinedglass and lower or equal to the index of the prism.

(c) Perform the adjustments of the optical path in accordance with the manufacturer’sspecifications to obtain a clear image of an equally spaced set of fringes in the compensatorplane.

(d) Using the goniometer, measure the angle θ (in degrees) of these fringes to the plane ofsymmetry (see Figure 8).

(e) In all instances where the surface stress is uniform (independent of direction), measure theangle θ , orienting the instrument’s plane of symmetry to measure stress parallel to thenearest edge.

(f) In those instances where the direction of maximum and minimum stress is uncertain (as aresult of irregular geometry, proximity of edges, or non-uniformity of heat-treating process),orient the instrument along direction α1, α2, α3 and measure the fringe pattern angle θ 1, θ 2, θ 3,in degrees, for each direction. Select α1, α2, α3 as follows:

α1 parallel to the nearest edge,α2 45° to the nearest edge, andα3 perpendicular to the nearest edge (See Figure 9).


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Figure 9 – Orientation of the instrument for measuring surface stress

H.5 Calculation and interpretation

The procedure for calculating the surface stress shall be as follows:

(a) Calculate the surface stress, S, using:

S = K tanθ (5)

where K is the instrument calibration constant determined by the manufacturer, in MPa (psi).

(b) In those instances where the surface stress is directional, assess the state of stress bycomparing the reading S in three directions α1, α2, α3 . If all three directions yield the samemeasured angles θ 1, θ 2, θ 3, within 1°, calculate the average angle, then obtain the surfacestress from equations 6.1 and 6.2 below:

3321

averageθθθ

θ++

= (6.1)

S = K⋅tanθ (6.2)

If measured angles θ 1, θ 2, and θ 3, differ by more than 1°, then using Equation 5, obtain the threestresses S1, S 2, and S 3, in directions α1, α2, and α3 and then calculate the principal stresses Smax, andSmin from equations 7.1 and 7.2 below:

2

322

2131

max - -

22

2

)( )(

SSSSSS

S ++=+

(7.1)

2

322

2131

min - -

2

2

2)( )(

SSSS

SSS ++=

+(7.2)


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Standards referred to:

ANSI Z97.1-1994 Glazing materials used in buildings – Safety performancespecifications and methods of test

AS 2193-1978 Methods for calibration and grading of force-measuring systemsof testing machines.

ASTM C 770-77 (1989) Test method for measurement of glass stress – Opticalcoefficient

ASTM D 756-1993 Practice for determination of weight and shape changes ofplastics under accelerated service conditions.

ASTM D 1499-1992 Recommended practice for operating light-and water-exposureapparatus (carbon-arc type) for exposure of plastics.

ASTM G 26-1995 Practice for operating light-exposure apparatus (xenon-arc type)with and without water for exposure of non-metallic materials

DIN 50017-1982 Condensation water test atmospheres

ISO 2859-0 : 1995 Sampling procedures for inspection by attributesPart 0: Introduction to the ISO 2859 attribute sampling system

ISO/IEC Guide 28 : 1982 General rules for a model third-party certification system forproducts

SS ISO 9000-1 : 1994 Quality management and quality assurance standardsPart 1 : 1994 Guidelines for selection and use

SS ISO 9004-1 : 1994 Quality management and quality system elementsPart 1 : 1994 Guidelines


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ABOUT THE SINGAPORE PRODUCTIVITY AND STANDARDS BOARD

The Singapore Productivity and Standards Board (PSB) was established in April 1996. Its mission is to raiseproductivity so as to enhance Singapore’s competitiveness and economic growth for a better quality of life for ourpeople. To achieve this mission, two broad thrusts are adopted -- developing world-class industries and creating afavourable environment for productivity improvement and innovation. The specific areas of focus are: small andmedium-sized enterprises (SMEs), productivity and innovation, and standardisation and metrology.

SMEs

As the lead agency spearheading the upgrading of SMEs, PSB adopts a total approach to develop SMEs into vibrantand resilient enterprises. At the enterprise level, it develops promising SMEs by enhancing their capabilities. At thesector level, it improves the productivity of domestic industries through industry-wide programmes. The broad-basedprogrammes include accelerating the adoption of e-commerce amongst SMEs, developing Singapore as an SME huband providing SMEs with access to finance. PSB also serves as the first point of contact for SMEs that needinformation and assistance.

Productivity and Innovation

PSB spearheads the national Productivity and Innovation Movement to cultivate a strong commitment to productivityand innovation and to foster a creative and thinking workforce that is able to translate ideas into action. As the leadagency in charge of workforce development, it works closely with employers, unions and other government agencies tobuild up the capabilities of the workforce and the training infrastructure in Singapore. Financial incentives are providedto help employers defray the cost of training their employees. Organisations are also encouraged to establish systemsthat drive continuous improvement and attain business excellence through the Singapore Quality Award and SingaporeQuality Class.

Standardisation and Metrology

As the national standards body and national metrology institute, PSB improves market access for Singapore’s exportsthrough its work on standardisation and metrology. Standardisation is also used as a major strategy to raise theproductivity of industries.

PSB enforces the Weights & Measures Act and Regulations to protect both consumers and traders by ensuring thatmarket transactions based on weights and measurement are accurate, fair and consistent with the relevant standards.As the Safety Authority, it administers the Singapore Consumer Protection (Safety Requirements) Registration Schemeto ensure compliance by industry on the registration of controlled goods.

ABOUT THE NATIONAL STANDARDISATION PROGRAMME

Under the national standardisation programme, PSB helps companies and industry to meet international standards andconformity requirements by creating awareness of the importance of standardisation to enhance competitiveness andimprove productivity, co-ordinating the development and use of Singapore Standards and setting up an informationinfrastructure to educate companies and industry on the latest developments.

PSB is vested with the authority to appoint a Standards Council to advise on the preparation, publication andpromulgation of Singapore Standards and Technical References and their implementation.

Singapore Standards are in the form of specifications for materials and products, codes of practice, methods of test,nomenclature, services, etc. The respective standards committee will draw up the standards before seeking finalapproval from the Standards Council. To ensure adequate representation of all viewpoints in the preparation ofSingapore Standards, all committees appointed consist of representatives from various interest groups which includegovernment agencies, professional bodies, tertiary institutions and consumer, trade and manufacturing organisations.

Technical References are transition documents developed to help meet urgent industry demand for specifications orrequirements on a particular product, process or service in an area where there is an absence of reference standards.Unlike Singapore Standards, they are issued for comments over a period of two years before assessment on theirsuitability for approval as Singapore Standards. All comments are considered when a technical reference is reviewed atthe end of two years to determine the feasibility of its transition to a Singapore Standard. Technical References cantherefore become Singapore Standards after two years, continue as Technical References for further comments or bewithdrawn.

In the international arena, PSB represents Singapore in the International Organisation of Standardisation (ISO), theInternational Electrotechnical Commission (IEC), the Asia-Pacific Economic Co-operation (APEC) Sub-committee forStandards and Conformance (SCSC) and in the ASEAN Consultative Committee for Standards and Quality (ACCSQ).


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