prEN 15682-1

SLOVENSKI STANDARD
oSIST prEN 15682-1:2007
01-julij-2007
Steklo v gradbeništvu - HS-preskus kaljenega zemljoalkalijskega silikatnega
varnostnega stekla - 1. del: Definicije in opis
Glass in building - Heat soaked thermally toughened alkaline earth silicate safety glass -
Part 1: Definition and description
Glas im Bauwesen - Heißgelagertes thermisch vorgespanntes Erdalkali-Silicat-
Einscheibensicherheitsglas - Teil 1: Definition und Beschreibung
Verre dans la construction - Verre de silicate alcalinoterreux de sécurité trempé et traité
Heat Soak - Partie 1 : Définition et description
Ta slovenski standard je istoveten z: prEN 15682-1
ICS:
81.040.20 Steklo v gradbeništvu Glass in building
oSIST prEN 15682-1:2007 en;fr;de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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EUROPEAN STANDARD
DRAFT
prEN 15682-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2007
ICS 81.040.20

English Version
Glass in building - Heat soaked thermally toughened alkaline
earth silicate safety glass - Part 1: Definition and description
Glas im Bauwesen - Heißgelagertes thermisch
vorgespanntes Erdalkali-Silicat-Einscheibensicherheitsglas
- Teil 1: Definition und Beschreibung
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 129.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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 Management Centre has the
same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 15682-1:2007: E
worldwide for CEN national Members.

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prEN 15682-1:2007 (E)
Contents Page
Foreword.4
Introduction .5
1 Scope .5
2 Normative references .5
3 Terms and definitions .6
4 Glass products.6
5 Manufacturing processes .6
5.1 General.6
5.2 Toughening process .7
5.3 Heat soak process cycle .7
5.3.1 General.7
5.3.2 Heating phase .7
5.3.3 Holding phase .8
5.3.4 Cooling phase .8
6 Heat soak process system.8
6.1 General.8
6.2 Oven .8
6.3 Glass support.8
6.4 Glass separation.9
6.5 Calibration .10
7 Fracture characteristics .10
8 Dimensions and tolerances .10
8.1 Nominal thickness and thickness tolerances.10
8.2 Width and length (sizes) .11
8.2.1 General.11
8.2.2 Maximum and minimum sizes.11
8.2.3 Tolerances and squareness .12
8.2.4 Edge deformation produced by vertical toughening .12
8.3 Flatness .13
8.3.1 General.13
8.3.2 Measurement of overall bow .13
8.3.3 Measurement of local bow.15
8.3.4 Limitation on overall and local bow.15
9 Edge work, holes, notches and cut-outs.16
9.1 Warning.16
9.2 Edge working of glass for toughening .16
9.3 Profiled edges .17
9.4 Round holes .17
9.4.1 General.17
9.4.2 Diameter of holes.17
9.4.3 Limitations on position of holes .17
9.4.4 Tolerances on hole diameters .19
9.4.5 Tolerances on position of holes.19
9.5 Notches and cut-outs .20
9.6 Shaped panes.20
10 Fragmentation test.21
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prEN 15682-1:2007 (E)
10.1 General .21
10.2 Dimensions and number of test specimens.21
10.3 Test procedure.21
10.4 Assessment of fragmentation.22
10.5 Minimum values from the particle count .23
10.6 Selection of the longest particle .23
10.7 Maximum length of longest particle .23
11 Other physical characteristics .23
11.1 Optical distortion.23
11.1.1 Heat soaked thermally toughened alkaline earth silicate safety glass produced by vertical
toughening .23
11.1.2 Heat soaked thermally toughened alkaline earth silicate safety glass produced by
horizontal toughening.23
11.2 Anisotropy (iridescence) .23
11.3 Thermal durability .24
11.4 Mechanical strength.24
11.5 Classification of performance under accidental human impact.24
12 Marking.24
Annex A (normative) Heat soak process system calibration test.25
A.1 Calibration criteria.25
A.2 Loading of oven and position for glass surface temperature measurement.25
A.3 Procedure.26
A.4 Records .26
A.5 Interpretation of the calibration test.27
Annex B (informative) Curved heat soaked thermally toughened alkaline earth silicate safety
glass.36
Annex C (informative) Examples of particle count.37
Bibliography.40

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prEN 15682-1:2007 (E)
Foreword
This document (prEN 15682-1:2007) has been prepared by Technical Committee CEN/TC 129 “Glass in
building”, the secretariat of which is held by NBN.
This document is currently submitted to the CEN Enquiry.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
For relationship with EU Directive(s), see informative Annex ZA, B, C or D, which is an integral part of this
document.
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prEN 15682-1:2007 (E)
Introduction
Heat soaked thermally toughened alkaline earth silicate safety glass has a safer breakage behaviour when
compared with annealed glass. It also has a known level of residual risk of spontaneous breakage arising from
the possible presence of critical nickel sulphide (NiS) inclusions in the thermally toughened alkaline earth
silicate glass.
NOTE 1 In this case it is about a statistical mean out of a big quantity of glass. It is impossible to determine separated
subjects from it for a building where definitely no "break" produced by NiS occurs. The breaking of glass caused by other
influences is not included herewith.
When used to offer protection under accidental human impact, heat soaked thermally toughened alkaline
earth silicate safety glass also should be classified according to EN 12600.
NOTE 2 CEN/TC 129/WG 8 is producing standards for the determination of the design strength of glass and is
preparing a design method.
1 Scope
This document specifies the heat soak process system together with tolerances flatness, edgework,
fragmentation and physical and mechanical characteristics of monolithic flat heat soaked thermally toughened
alkaline earth silicate safety glass for use in buildings.
Information on curved heat soak thermally toughened alkaline earth silicate safety glass is given in annex B,
but this product does riot form part of this document.
Other requirements, not specified in this document, can apply to heat soaked thermally toughened alkaline
earth silicate safety glass which is incorporated into assemblies, e.g. laminated glass or insulating units, or
undergo an additional treatment, e.g. coating. The additional requirements are specified in the appropriate
product standard. Heat soak thermally toughened alkaline earth silicate safety glass, in this case, does not
lose its mechanical or thermal characteristics.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 673, Glass in Building – Determination of Thermal Transmittance (U-Value) Calculation Method
EN 1096-1, Glass in building — Coated glass — Part 1: Definitions and classification.
EN 12600, Glass in building — Pendulum test — Impact test method and classification for flat glass.
EN 14178-1, Glass in building – Basic alkaline earth silicate glass products – Part 1: Floatglass
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prEN 15682-1:2007 (E)
3 Terms and definitions
For the purposes of this document the following terms and definitions apply:
3.1
heat soaked thermally toughened alkaline earth silicate safety glass
glass within which a permanent surface compressive stress has been induced in order to give it greatly
increased resistance to mechanical and thermal stress and prescribed fragmentation characteristics and
which has a known level of residual risk of spontaneous breakage due to the presence of critical nickel
sulphide (NiS) inclusions
3.2
level of residual risk
risk of spontaneous breakage of heat soaked thermally toughened alkaline earth silicate safety glass on a
statistical basis due to the presence of critical nickel sulphide inclusions shall be not more than one breakage
per 400 tonnes of heat soaked thermally toughened alkaline earth silicate safety glass
3.3
flat heat soaked thermally toughened alkaline earth silicate safety glass
heat soaked thermally toughened alkaline earth silicate safety glass that has not been deliberately given a
specific profile during manufacture
3.4
heat soaked enamelled thermally toughened alkaline earth silicate safety glass
heat soaked thermally toughened alkaline earth silicate safety glass which has a ceramic frit fired into the
surface during the toughening process. After toughening the ceramic frit becomes an integral part of the glass
3.5
horizontal toughening
process in which the glass is supported on horizontal rollers
3.6
vertical toughening
process in which the glass is suspended by tongs
4 Glass products
Heat soaked thermally toughened alkaline earth silicate safety glass is made from a monolithic alkaline earth
silicate glass product generally corresponding to one of the following standards:
 coated glass according to EN 1096-1;
 EN 14178, Glass in building – Basic alkaline earth silicate glass products – Part 1: Float glass.
5 Manufacturing processes
5.1 General
Heat soaked thermally toughened alkaline earth silicate safety glass is manufactured as follows:
Basic alkaline earth silicate glass products (see Clause 4) are cut to size, shaped and edge worked (see
Clause 9).
The prepared glass panes are then thermally toughened (see 5.2).
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prEN 15682-1:2007 (E)
The thermally toughened panes are then subjected to the heat soak process cycle.
After manufacture the heat soaked thermally toughened alkaline earth silicate glass shall comply with the
fragmentation test (see Clause 10) and mechanical strength requirement (see 11.4).
5.2 Toughening process
The cut, shaped and edge worked glasses are toughened. The horizontal or vertical toughened glass shall
comply with the flatness criteria (see 8.3).
The thermally toughened alkaline earth silicate glass shall have a level of fragmentation that will ensure that
after the glass has been through the heat soak process, and subsequently tested to the fragmentation test
(see Clause 10), it shall comply with 10.5.
5.3 Heat soak process cycle
5.3.1 General
The heat soak process cycle consists of a heating phase, a holding phase and a cooling phase (see Figure1).

Key
T glass temperature at any point, °C
d ambient temperature
t time, h a heating phase
1 first glass to reach 280 °C b holding phase
2 last glass to reach 280 °C c cooling phase
Figure 1 — Heat soak process cycle
5.3.2 Heating phase
The heating phase commences with all the glasses at ambient temperature and concludes when the surface
temperature of the last glass reaches 280 °C. The time to reach this temperature is defined in the calibration
process. This time will be dependent on the size of the oven, the amount of glass to be treated, the separation
between glasses and the heating system capacity.
NOTE 1 The glass separation and rate of heating should be controlled to minimise the risk of glass breakage as a
result of thermal stress.
To facilitate economic heating, the air temperature within the oven may exceed 320 °C. However, the glass
surface temperature shall not be allowed to exceed 320 °C. The period of glass surface temperature in excess
of 300 °C shall be minimised.
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prEN 15682-1:2007 (E)
NOTE 2 When the temperature of the glass exceeds 300 °C, care should be taken to ensure that the properties of the
heat soaked thermally toughened alkaline earth silicate safety glass are not significantly altered i.e. they continue to meet
Clause 10.
5.3.3 Holding phase
The holding phase commences when the surface temperature of all the glasses has reached a temperature of
280 °C. The duration of the holding phase is 2 h.
Precise oven control is necessary in order to ensure that the glass surface temperature shall be maintained in
the range of 290 °C ± 10 °C during the holding phase.
5.3.4 Cooling phase
The cooling phase commences when the last glass to reach 280 °C has completed its holding phase, i.e.
been held for two hours at 290 °C ± 10 °C. During this phase the glass temperature shall be brought down to
ambient temperature.
The cooling phase can be concluded when the air temperature in the oven reaches 70 °C.
NOTE The rate of cooling should be controlled to minimise the risk of glass breakage as a result of thermal stress.
6 Heat soak process system
6.1 General
The heat soak process system consists of:
 the oven (see 6.2),
 the glass support (see 6.3),
 separation system (see 6.4).
The oven shall be calibrated, see 6.5 and Annex A, and this determines the method of operation of the heat
soak process system during manufacture of heat soaked thermally toughened alkaline earth silicate safety
glass.
6.2 Oven
The oven shall be heated by convection and shall allow an unhindered air circulation around each glass pane.
In the event of glass breakage the airflow shall not be hindered. The airflow in the oven shall be led parallel to
the glass surfaces.
NOTE The openings for the air ingress/egress should be designed to ensure that fragments of broken glass do not
cause blockages.
6.3 Glass support
Glasses may be supported vertically or horizontally. The glasses shall not be fixed or clamped, they have to
be supported to allow free movement.
NOTE Vertically means true vertical or up to 15° either side of true vertical.
The distance between glasses affects the airflow, heat exchange and the heating time. Glass to glass contact
shall not be allowed.
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6.4 Glass separation
The glasses shall be separated in a manner that does not hinder the airflow. The separators shall also not
hinder the airflow e.g. see Figure 2.
Dimensions in mm

Figure 2 — Example of a vertical glass support
The minimum separation of the glasses shall be determined during the calibration of the oven, see 6.5 and
Annex A.
NOTE 1 Generally, a minimum separation of 20 mm is recommended. (See Figure 3.)
NOTE 2 If glasses of very different size are put on the same stillage, they will require greater separation in order to
prevent glass breakage when the furnace is opened alter the heat soak process. The same applies to glasses with holes,
notches and cut-outs.
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prEN 15682-1:2007 (E)
Dimensions in millimetres

Figure 3 — Recommend separation between glass
The positioning of the separators, material of the manufacture and their shape shall be specified during the
calibration test of the oven and shall be reproduced during the manufacturing process.
6.5 Calibration
The heat soak system, e.g. oven, glass separation, separators, etc., shall be calibrated, see Annex A.
The calibration shall determine the heating phase of the process, glass separation distance, the positioning,
material and shape of separators, the type and positioning of stillage(s) and define the operating conditions for
use during manufacture.
7 Fracture characteristics
In the event of breakage, heat soaked thermally toughened alkaline earth silicate safety glass fractures into
numerous small pieces, the edges of which are generally blunt.
NOTE Fragmentation in service does not always correspond to that described in clause 10, due to restraint from
fixing or reprocessing (e.g. laminating), or due to the cause of fracture.
8 Dimensions and tolerances
8.1 Nominal thickness and thickness tolerances
The nominal thicknesses and thickness tolerances are those given in the relevant product standard (see
Clause 4), some of which are reproduced in Table 1.
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prEN 15682-1:2007 (E)
Table 1 — Nominal thicknesses and thickness tolerances
Dimensions in millimetres
Thickness tolerances for glass type
Nominal thickness
d
Float
4
± 0,2
5
± 0,2
6
± 0,2
8
± 0,3
10
± 0,3
12
± 0,3
15
± 0,5

The thickness of a pane shall be determined as for the basic product. The measurement shall be taken at the
centres of the 4 sides, and away from the area of any tong marks (see Figure 6), which may be present.
8.2 Width and length (sizes)
8.2.1 General
When heat soaked thermally toughened alkaline earth silicate safety glass dimensions are quoted for
rectangular panes, the first dimension shall be the width, B, and the second dimension the length, H, as
shown in figure 4. It shall be made clear which dimension is the width, B, and which is the length, H, when
related to its installed position.

Figure 4 — Examples of width, B, and length, H, relative to the pane shape
NOTE For heat soaked thermally toughened alkaline earth silicate safety glass manufactured from patterned glass,
the direction of the pattern should be specified relative to one of the dimensions.
8.2.2 Maximum and minimum sizes
For maximum and minimum sizes, the manufacturer shall be consulted.
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prEN 15682-1:2007 (E)
8.2.3 Tolerances and squareness
The nominal dimensions for width and length being given, the finished pane shall not be larger than a
prescribed rectangle resulting from the nominal dimensions increased by the tolerance, t, or smaller than a
prescribed rectangle reduced by the tolerance, t. The sides of the prescribed rectangles are parallel to one
another and these rectangles shall have a common centre (see Figure 5). The limits of squareness shall be
determined by the prescribed rectangles. Tolerances are given in Table 2.

Figure 5 — Tolerance limits for dimensions of rectangular panes
Table 2 — Tolerances on width, B, and length, H
Dimensions in millimetres
Tolerance, t
Nominal dimension of side,
nominal glass thickness, nominal glass thickness,
B or H
d > 12
d ≤ 12
≤ 2 000 ± 2,5 (horizontal toughening) ± 3,0
± 3,0 (vertical toughening)
2 000 < B or H ≤ 3 000 ± 3,0 ± 4,0
> 3 000 ± 4,0 ± 5,0

8.2.4 Edge deformation produced by vertical toughening
The tongs used to suspend the glass during toughening can result in surface depressions, known as tong
marks (see Figure 6). The centres of the tong marks may be situated up to a maximum of 20 mm in from the
edge. A deformation of the edge less than 2 mm can be produced in the region of the tong mark and there can
also be an area of optical distortion. These deformations shall be included in the tolerances in Table 2.
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Key
1 deformation
2 up to 20 mm
3 tong mark
4 100 mm radius maximum area of optical distortion
Figure 6 — Tong mark deformation
8.3 Flatness
8.3.1 General
By the very nature of the toughening process, it is not possible to obtain a product as flat as annealed glass.
The difference depends on the nominal thickness, the dimensions and the ratio between the dimensions.
Therefore a distortion known as overall bow may occur. There are two kinds of bow (see Figure 7):
 overall or general bow,
 local bow.
NOTE 1 Overall bow can, in general, be accommodated by the framing system.
NOTE 2 Local bow needs to be allowed for in the glazing materials and the weather seals. For special requirements
the manufacturers should be consulted.
8.3.2 Measurement of overall bow
The pane of glass shall be placed in a vertical position and supported on its longer side by two load bearing
blocks at the quarter points (see Figure 8).
The deformation shall be measured along the edges of the gl
...