BS EN 572-8:2012+A1:2016

BSI Standards Publication

Glass in building — Basic
soda-lime silicate glass products

Part 8: Supplied and final cut sizes

BS EN 572-8:2012+A1:2016 BRITISH STANDARD

National foreword

This British Standard is the UK implementation of
EN 572-8:2012+A1:2016. It supersedes BS EN 572-8:2012 which
is withdrawn.

The start and finish of text introduced or altered by amendment is
indicated in the text by tags. Tags indicating changes to CEN text carry
the number of the CEN amendment. For example, text altered by CEN
amendment A1 is indicated by !".

The UK participation in its preparation was entrusted by Technical
Committee B/520, Glass and glazing in building, to Subcommittee
B/520/1, Basic and transformed glass products.

A list of organizations represented on this subcommittee can be
obtained on request to its secretary.

This publication does not purport to include all the necessary
provisions of a contract. Users are responsible for its correct

application.

© The British Standards Institution 2016.
Published by BSI Standards Limited 2016

ISBN 978 0 580 89953 9

ICS 81.040.20

Compliance with a British Standard cannot confer immunity from
legal obligations.

This British Standard was published under the authority of the
Standards Policy and Strategy Committee on 31 July 2012.

Amendments/corrigenda issued since publication

Date Text affected

30 June 2016 Implementation of CEN amendment A1:2016

EUROPEAN STANDARD EN 572-8:2012+A1
NORME EUROPÉENNE
EUROPÄISCHE NORM February 2016

ICS 81.040.20 Supersedes EN 572-8:2012

English Version

Glass in building - Basic soda-lime silicate glass products -

Part 8: Supplied and final cut sizes

Verre dans la construction - Produits verriers de Glas im Bauwesen - Basiserzeugnisse aus Kalk-
silicate sodo-calcique de base - Partie 8 : Mesures Natronsilicatglas - Teil 8: Liefermaße und Festmaße

livrées et mesures découpées finales

This European Standard was approved by CEN on 11 May 2012 and includes Amendment 1 approved by CEN on 22 November
2015.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels


© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 572-8:2012+A1:2016 E
worldwide for CEN national Members.

BS EN 572-8:2012+A1:2016
EN 572-8:2012+A1:2016 (E)

Contents Page

European foreword....................................................................................................................................................... 3

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 Glass products .................................................................................................................................................. 9

5 Dimensional requirements.......................................................................................................................... 9
5.1 Manufacturing dimensions.......................................................................................................................... 9
5.1.1 Supplied sizes ................................................................................................................................................... 9
5.1.2 Final cut sizes.................................................................................................................................................... 9
5.2 Thickness ........................................................................................................................................................ 10
5.2.1 General............................................................................................................................................................. 10
5.2.2 Tolerances ...................................................................................................................................................... 10
5.3 Length, width, and squareness................................................................................................................ 11

6 Quality requirements ................................................................................................................................. 13
6.1 General............................................................................................................................................................. 13
6.2 Methods of observation and measurement ........................................................................................ 14

6.2.1 Optical faults .................................................................................................................................................. 14
6.2.2 Visual faults .................................................................................................................................................... 14
6.2.3 Edge defects for final cut sizes................................................................................................................. 15
6.3 Acceptance levels ......................................................................................................................................... 16
6.3.1 Optical faults .................................................................................................................................................. 16
6.3.2 Visual faults .................................................................................................................................................... 17

Annex A (normative) Test methods of examination for visual faults — Spot faults and
linear/extended faults ............................................................................................................................... 23

A.1 Float glass (EN 572-2:2012) ..................................................................................................................... 23
A.1.1 Method of observation ............................................................................................................................... 23
A.1.2 Linear/extended faults .............................................................................................................................. 23
A.2 Polished wired glass (EN 572-3:2012) ................................................................................................. 23
A.2.1 Spot faults ....................................................................................................................................................... 23
A.2.2 Linear/extended faults .............................................................................................................................. 24
A.3 Drawn sheet glass (EN 572-4:2012) ...................................................................................................... 24
A.3.1 Spot faults ....................................................................................................................................................... 24
A.3.2 Linear/extended faults .............................................................................................................................. 24
A.4 Patterned glass (EN 572-5:2012) and wired patterned glass (EN 572-6:2012) — Spot

and linear/extended faults....................................................................................................................... 24

Annex B (normative) Method for measuring spot fault size (including halo) ...................................... 25
B.1 Conditions of observation ......................................................................................................................... 25
B.2 Measurement of the size of the spot fault including the halo....................................................... 26

Bibliography................................................................................................................................................................. 27

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European foreword

This document (EN 572-8:2012+A1:2016) has been prepared by Technical Committee CEN/TC 129
“Glass in building”, the secretariat of which is held by NBN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by August 2016, and conflicting national standards shall
be withdrawn at the latest by August 2016.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document includes Amendment 1 approved by CEN on 22 November 2015.
This document supersedes !EN 572-8:2012".
The start and finish of text introduced or altered by amendment is indicated in the text by tags !".
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
!EN 572-8:2012 was" a revision of EN 572-8:2004. The main changes in this edition !were":
a) a new method of determination of squareness;
b) a new method of measurement for spot fault (including halo) and an adaptation of the related

requirements.
The European Standard EN 572:2012 “Glass in building — Basic soda-lime silicate glass products”
consists of the following parts:
— Part 1: Definitions and general physical and mechanical properties;
— Part 2: Float glass;
— Part 3: Polished wired glass;
— Part 4: Drawn sheet glass;

— Part 5: Patterned glass;
— Part 6: Wired patterned glass;
— Part 7: Wired or unwired channel shaped glass;
— Part 8: Supplied and final cut sizes;
— Part 9: Evaluation of conformity/Product standard.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,

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EN 572-8:2012+A1:2016 (E)
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

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1 Scope

This European Standard specifies dimensional and minimum quality requirements (in respect of optical
and visual faults) for basic soda-lime silicate glass products, as defined in EN 572-1:2012, for use in
building. It applies to supplied sizes or cut sizes for final end use.
This European Standard does not apply to final cut sizes having a dimension less than 100 mm or a
surface area less than 0,05 m².
This European Standard does not apply to float glass supplied as jumbo, split sizes or oversize plates

nor to polished wired glass, drawn sheet glass, patterned glass, patterned wired glass supplied as stock
sizes. For specifications regarding these types of glass, see EN 572-2:2012, EN 572-3:2012,
EN 572-4:2012, EN 572-5:2012 and EN 572-6:2012 respectively.
This European Standard does not apply to final cut sizes of wired or unwired channel shaped glass For
specifications on this type of glass, see EN 572-7:2012.

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 572-1:2012, Glass in building — Basic soda-lime silicate glass products — Part 1: Definitions and
general physical and mechanical properties

EN 572-2:2012, Glass in building — Basic soda lime silicate glass products — Part 2: Float glass

EN 572-3:2012, Glass in building — Basic soda lime silicate glass products — Part 3: Polished wired glass

EN 572-4:2012, Glass in building — Basic soda lime silicate glass products — Part 4: Drawn sheet glass

EN 572-5:2012, Glass in building — Basic soda lime silicate glass products — Part 5: Patterned glass

EN 572-6:2012, Glass in building — Basic soda lime silicate glass products — Part 6: Wired patterned
glass

3 Terms and definitions

For the purposes of document, the terms and definitions given in EN 572-1:2012, EN 572-2:2012,
EN 572-3:2012, EN 572-4:2012, EN 572-5:2012 and EN 572-6:2012 and the following apply.
3.1

supplied size
pane of glass that has been supplied either as raw material for further processing and/or cutting down
to a size for installation

Note 1 to entry: This is a size outside those given in EN 572-2:2012, EN 572-3:2012, EN 572-4:2012,
EN 572-5:2012 and EN 572-6:2012, i.e. jumbo, split sizes or oversize plates for float glass and supplied sizes for
polished wired, drawn sheet, patterned and wired patterned glass.

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3.2
final cut size
pane of glass that has been cut down to the dimensions required either for installation or processing
into a final product

Note 1 to entry: Examples of processed final products are insulating glass units and thermally toughened safety
glass of those dimensions.

3.3
length, H, and width, B
defined with reference to the direction of draw of the glass ribbon as shown in Figures 1 and 2

Key
1 direction of draw

Figure 1 — Relationship between length, width and direction of draw
for float, polished wired, patterned and wired patterned glass


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Key
1 direction of draw

Figure 2 — Relationship between length, width and direction of draw for drawn sheet glass
3.4
optical fault
fault which leads to distortions in the appearance of objects observed through the glass
3.5
visual fault
fault which alters the visual quality of the glass

Note 1 to entry: Visual faults include spot faults and linear/extend faults with patterned faults and/or wire
faults, depending on type of product.

3.6
spot fault
spherical or quasi-spherical faults which are produced by differing mechanisms and are defined for a
specific glass product type/manufacturing process
3.6.1
spot fault (float glass)
nucleus which is generally accompanied by a halo of distorted glass
[SOURCE: EN 572-2:2012, 3.6]
3.6.2
halo (float glass)
area locally distorted, generally around a point defect

[SOURCE: EN 572-2:2012, 3.7]

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3.6.3
spherical or quasi-spherical spot fault (polished wired, patterned and wired patterned glass)
spot fault whose larger dimension is less than or equal to twice the smaller dimension

[SOURCE: EN 572-3:2012, 3.5; EN 572-5:2012, 3.4; EN 572-6:2012, 3.4]

3.6.4
elongated spot fault (polished wired, patterned and wired patterned glass)
spot fault whose larger dimension is more than twice the smaller dimension

[SOURCE: EN 572-3:2012, 3.6; EN 572-5:2012, 3.5; EN 572-6:2012, 3.5]

3.6.5
spot fault (drawn sheet glass)
fault which can be on or in the glass, in the form of gaseous inclusion, solid inclusion, mark or deposit of
small size

[SOURCE: EN 572-4:2012, 3.8]

3.7
concentration, c (drawn sheet glass)
sum of the lengths of gaseous inclusions > 1,0 mm in any circle of 400 mm diameter


[SOURCE: EN 572-4:2012, 3.11]

3.8
linear/extended fault
fault which can be on or in the glass, in the form of deposits, marks or scratches that occupy an
extended length or area

3.9
pattern fault (patterned and wired patterned glass)
deviation of the pattern relative to a reference such as a line or straight edge

[SOURCE: EN 572-5:2012, 3.7; EN 572-6:2012, 3.7]

3.10
deviation of the pattern (patterned and wired patterned glass)
deviation, x, of the pattern

[SOURCE: EN 572-5:2012, 3.8; EN 572-6:2012, 3.8]

3.11
wire fault (polished wired and wired patterned glass)
deviation of the wire, penetration of the glass surface by the wire or break in the wire in the body of the
glass

[SOURCE: EN 572-3:2012, 3.8; EN 572-6:2012, 3.9]

3.12
deviation of the wire (polished wired and wired patterned glass)
deviation, y, of the wire relative to a reference such as a line or straight edge


[SOURCE: EN 572-3:2012, 3.9; EN 572-6:2012, 3.10]

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3.13
edge defect
defect which can occur on the edge of a cut size piece in the form of entrant and emergent fault and/or
bevel

4 Glass products

Glass products according to the following standards can be offered as supplied sizes or final cut sizes:

— float glass EN 572-2:2012;

— polished wired glass EN 572-3:2012;

— drawn sheet glass EN 572-4:2012;

— patterned glass EN 572-5:2012;

— wired patterned glass EN 572-6:2012.

5 Dimensional requirements

5.1 Manufacturing dimensions


5.1.1 Supplied sizes

Supplied sizes cover glass delivered in the sizes given in Table 1.

Table 1 — Dimensions of supplied sizes

Dimensions in millimetres

Glass type Nominal dimensions

B H

Float glass < 3 210 a Any

Polished wired glass < 1 980 Any
1 980 to 2 540 < 1 650

New antique drawn sheet glass; < 1 450 Any

Drawn sheet glass for renovation 1 450 to 2 160 < 1 200

Drawn sheet glass < 2 440 Any
2 440 to 2 880 < 1 600

Patterned glass < 1 260 Any
1 260 to 2 520 < 2 100

Wired patterned glass < 1 500 Any
1 500 to 2 520 < 1 380


a Under exceptional production requirements, B may be less than 3 210 mm but never below 3 150 mm. In such cases,
supplied sizes are those with B < 3 150 mm.

5.1.2 Final cut sizes
Final cut sizes cover glass delivered in the final dimensions.

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The minimum final cut size shall have dimensions H or B not less than 100 mm and a minimum surface
area of not less than 0,05 m².

5.2 Thickness

5.2.1 General

The actual thickness shall be the average of four measurements, taken to the nearest 0,01 mm, one
taken at the centre of each side. Measurement shall be made by means of either:
a) an instrument of the calliper micrometer type, applicable for float glass, polished wired glass and

drawn sheet glass; or

b) an instrument of the plate gauge type with a diameter of (50 ± 5) mm, applicable for patterned
glass and wired patterned glass.

5.2.2 Tolerances

The actual thickness, rounded to the nearest 0,1 mm shall not vary from the nominal thickness by more

than the tolerances shown in Tables 2 and 3.
!

Table 2 — Nominal thicknesses, limits and tolerances
for float glass, polished wired glass, patterned glass and wired patterned glass

Dimensions in millimetres

Nominal Thickness limits and tolerances on thickness
thickness
Float Polished wired Patterned Wired patterned
glass glass glass glass

2 ± 0,2

3 ± 0,2 ± 0,5

4 ± 0,2 ± 0,5

5 ± 0,2 ± 0,5

6 ± 0,2 ± 0,5 ± 0,6

7 6,2 to 7,4 ± 0,7

8 ± 0,3 ± 0,8 ± 0,8

9 8,0 to 10,5

10 ± 0,3 9,1 to 10,9 ± 1,0


12 ± 0,3 ± 1,5

14 ± 1,5

15 ± 0,5 ± 1,5

19 ± 1,0 ± 2,0

25 ± 1,0

Key

Not manufactured

"

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Table 3 — Nominal thicknesses, and thickness tolerances
for new antique drawn sheet glass, drawn sheet glass for renovation and drawn sheet glass

Dimensions in millimetres

Nominal New antique drawn Tolerance on thickness Drawn sheet glass
thickness sheet glass
Drawn sheet glass

for renovation

2 ± 0,2 ± 0,2

2,8 ± 0,3

3 ± 0,3 ± 0,2

4 ± 0,3 ± 0,3 ± 0,2

5 - ± 0,3 ± 0,3

6 ± 0,3 ± 0,3 ± 0,3

8 ± 0,4 ± 0,4

10 ± 0,5

12 ± 0,6

Key

Not manufactured

5.3 Length, width, and squareness

The tolerances, t, on the nominal dimensions length, H, and width, B, is given in Table 4 for float glass
and drawn sheet glass and in Table 5 for polished wired glass and wired patterned glass and in Table 6
for patterned glass.


Table 4 — Tolerance, t, on the nominal dimensions length and width —
Float glass and drawn sheet glass

Dimensions in millimetres

Tolerance t

Thickness Supplied size Final cut sizes
1 500 < (H, B) ≤ 3 000
(H, B) ≤ 1 500 (H, B) > 3 000

2, 2,8, 3, 4, 5, 6 ± 4,0 ± 1,0 ± 1,5 ± 2,0

8, 10, 12 ± 4,0 ± 1,5 ± 2,0 ± 2,5

15 ± 4,0 ± 2,0 ± 2,5 ± 3,0

19, 25 ± 5,0 ± 2,5 ± 3,0 ± 3,5

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Table 5 — Tolerance, t, on the nominal dimensions length and width —
Polished wired glass and wired patterned glass

Dimensions in millimetres

Glass type Nominal glass Tolerance t

thickness, d Final cut sizes
Supplied sizes

(H, B) ≤ 1 500 1 500 < (H, B) ≤ 3 000 (H, B) > 3 000

Polished wired 7 and 10 ± 4 ± 1,5 ± 2,0 ± 2,5

Wired patterned 6, 7, 8, 9 ± 5

Table 6 — Tolerance, t, on the nominal dimensions length and width — Patterned glass

Dimensions in millimetres

Tolerance t

Thickness Supplied sizes Final cut sizes
1 500 < (H, B) ≤ 3 000
(H, B) ≤ 1 500 (H, B) > 3 000

3, 4, 5, 6 ± 3 ± 1,0 ± 1,5 ± 2,0

8, 10 ± 4 ± 1,5 ± 2,0 ± 2,5

12, 14, 15, 19 ± 5 ± 2,0 ± 2,5 ± 3,0

The limits of squareness are described by difference between diagonals. Limits are given in Table 7 for
float glass, Table 8 for drawn sheet glass, Table 9 for polished wired glass and wired patterned glass and
Table 10 for patterned glass.

Table 7 — Limit on the difference between diagonals for float glass


Dimensions in millimetres

Nominal glass Limit on the difference between diagonals
thickness, d Supplied and final cut sizes
1 500 < (H, B) ≤ 3 000
(H, B) ≤ 1 500 (H, B) > 3 000

2, 3, 4, 5, 6 3 4 5

8, 10, 12 4 5 6

15, 19, 25 5 6 8

Table 8 — Limit on the difference between diagonals
for antique drawn sheet glass, drawn sheet glass for renovation and drawn sheet glass

Dimensions in millimetres

Nominal glass Limit on the difference between diagonals
thickness, d Supplied and final cut sizes
1 500 < (H, B) ≤ 3 000
(H, B) ≤ 1 500 (H, B) > 3 000

2, 2,8, 3, 4, 5, 6 3 4 5

8, 10 4 5 6

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Table 9 — Limit on the difference between diagonals
for polished wired glass and wired patterned glass

Dimensions in millimetres

Limit on the difference between diagonals

Glass type Nominal glass Supplied and final cut sizes
thickness, d
Polished wired
Wired patterned (H, B) ≤ 1 500 1 500 < (H, B) ≤ 3 000 (H, B) > 3 000

7 and 10

3 4 5

6, 7, 8, 9

Table 10 — Limit on the difference between diagonals for patterned glass

Dimensions in millimetres

Nominal glass Limit on the difference between diagonals
thickness, d Supplied and final cut sizes
1 500 < (H, B) ≤ 3 000
(H, B) ≤ 1 500 (H, B) > 3 000


3, 4, 5, 6 3 4 5

8, 10, 12 4 5 6

14, 15, 19 5 6 8

6 Quality requirements

6.1 General
One quality level is considered for each product in this European Standard.
The quality of the following products is determined by evaluation of the optical and visual faults:
a) float glass;

b) polished wired glass;

c) drawn sheet glass.

The quality of the following products is determined by evaluation of the visual faults only:
d) new antique drawn sheet glass;

e) drawn sheet glass for renovation;

f) patterned glass;

g) wired patterned glass.

For final cut sizes, the quality of the cut edge is considered.
Optical faults (see EN 572-2:2012, EN 572-3:2012, EN 572-4:2012) are determined on the dimensions
of glass as manufactured. Visual faults can be checked for all dimensions, i.e. supplied sizes or final cut
sizes, with the level of acceptance being related to the dimensions.


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6.2 Methods of observation and measurement

6.2.1 Optical faults

The methods of measurement/determination are specified in the appropriate parts of EN 572 (Parts 2,
3, 4) and will therefore not be detailed in this European Standard.
For float glass, the critical viewing angle is measured. For polished wired glass and drawn sheet glass,
the presence of disturbing distortions is noted.
6.2.2 Visual faults

6.2.2.1 Spot faults

The methods of examination for spot faults are given for the various glass products in Annex A. These
methods are identical to and copied from the appropriate parts of EN 572.
6.2.2.2 Linear/extended faults

The methods of examination for linear/extended faults are given for the various glass products in
Annex A. These methods are identical to and copied from the appropriate parts of EN 572.
6.2.2.3 Pattern faults

A reference, such as a line or straight edge, is placed on the glass as shown in Figure 3. The deviation, x,
of the pattern in relation to the reference is measured.

a) Out of square b) Waviness c) Bow


NOTE The scale of these drawings has been exaggerated in order to be explicit about the types of deviation.

Figure 3 — Representations of the type of pattern faults

6.2.2.4 Wire faults

A reference, such as a line or straight edge, is placed parallel to the direction of the wires. The deviation,
y, of the wire in relation to the reference is measured (see Figure 4).
Any penetration of the glass surface by the wire is noted.
Any breaks in the wire are noted.

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a) Out of square b) Waviness c) Bow

NOTE The scale of these drawings has been exaggerated in order to be explicit about the types of deviation..

Figure 4 — Representations of the types of wire faults

6.2.3 Edge defects for final cut sizes
6.2.3.1 Entrant and emergent faults
Entrant and emergent faults are shown in Figures 5 and 6. The dimensions h1, h2 and p and the glass
thickness e are measured.

Figure 5 — Entrant and emergent faults — Surface view


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Figure 6 — Entrant faults — Edge view
6.2.3.2 Bevel
The bevel fault is shown in Figure 7. The dimension d and the glass thickness, e, are measured.

Figure 7 — Bevel — Edge view
6.3 Acceptance levels
6.3.1 Optical faults
For float glass, when examined by the method in EN 572-2:2012, the critical viewing angle, a, shall be
greater than 50°.
For polished wired glass and drawn sheet glass, when examined by the methods in EN 572-3:2012 and
EN 572-4:2012 respectively, the observer shall not see any disturbing distortions within the glass pane.

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6.3.2 Visual faults

6.3.2.1 General

When examined and determined in accordance with 6.2.2.1, 6.2.2.2, 6.2.2.3, 6.2.2.4 and 6.2.3 for spot
faults, linear/extended faults, patterned faults, wire faults and edge defects respectively, the acceptance
levels are given for the various products and fault types as follows:
— 6.3.2.2 for spot faults for supplied sizes;


— 6.3.2.3 for spot faults for final cut sizes;

— 6.3.2.4 for linear/extended faults for supplied sizes;

— 6.3.2.5 for linear/extended faults for final cut sizes;

— 6.3.2.6 for pattern faults;

— 6.3.2.7 for wire faults;

— 6.3.2.8 for edge defects for final cut sizes.

6.3.2.2 Spot faults for supplied sizes

6.3.2.2.1 General

The allowable levels of spot faults, in supplied sizes, are dependent on the specific product type and are
detailed below.
6.3.2.2.2 Float glass

The allowable numbers for each of the categories of faults (see Table A.1), are shown in Table 11.

Table 11 — Acceptance levels for spot faults in supplied sizes of float glass

Category of fault S ≤ 5 m2 Surface area of pane (S) 10 m2 < S ≤ 20 m2
5 m2 < S ≤ 10 m2
A 2 No limitation 5
B a Not allowed 3 1
C 1

D Not allowed

a The minimum distance between category B faults shall be not less than 500 mm.

6.3.2.2.3 Polished wired glass

The acceptance levels for each size/position of spot faults in polished wired glass are shown in
Table 12.

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Table 12 — Acceptance levels for spot faults in supplied sizes of polished wired glass

Position relative Acceptance levels for faults of various larger dimensions
to wire
Type of fault ≤ 1,0 mm ≤ 2,0 mm > 1,0 mm > 2,0 mm > 4,0;
≤ 4,0 mm ≤ 4,0 mm

Spherical and In contact or Acceptable 0,5 per m² Not acceptable
quasi-spherical ≤ 2 mm from wire

> 2 mm from wire Acceptable 0,5 per m² Not acceptable

Acceptance level for faults of various lengths

Type of Width of ≤ 1,0 mm ≤ 4,0 mm > 1,0 mm > 4,0 mm > 5,0 mm > 10,0 mm > 15,0 mm
fault fault Accepted ≤ 5,0 mm ≤ 10,0 ≤ 15,0 mm Not accepted

mm

Elongated ≤ 1,0 mm ≤ 10 per ≤ 3 per m² ≤ 2 per m²
spot faults > 1,0 mm m²

≤ 0,5 per m² Not accepted

Key
Not applicable

6.3.2.2.4 Drawn sheet glass

The allowable numbers for each size of spot fault are shown in Table 13 for new antique drawn sheet
glass and drawn sheet glass for renovation and in Table 14 for drawn sheet glass.

Table 13 — Acceptance levels for spot faults and linear/extended faults
in new antique drawn sheet glass and drawn sheet glass for renovation

Types of faults Acceptance criteria
1 Spot faults
1.1 Gaseous inclusions Acceptable
• ≤ 5 mm 2/m²
• ≥ 5 mm ≤ 30 mm Not acceptable
• > 30 mm
1.2 Solid spot faults 1 per m²/5 per m² if tinted
• ≤ 2 mm 1 per m²
• > 2 mm ≤ 5 mm Not accepted
• > 5mm
2 Linear/extended faults Acceptable
• ≤ 10 mm 2/m²

• > 10 mm ≤ 50 mm Not acceptable
• > 50 mm

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