oSIST prEN 14178-1:2017

SLOVENSKI STANDARD
01-september-2017
Steklo v gradbeništvu - Osnovni izdelki iz zemljoalkalijskega silikatnega stekla - 1.
del: Ravno steklo
Glass in building - Basic alkaline earth silicate glass products - Part 1: Float glass
Glas im Bauwesen - Basiserzeugnisse aus Erdalkali­Silicatglas - Teil 1: Floatglas
Verre dans la construction - Verre de silicate alcalino-terreux de base - Partie 1 : Glace
flottée
Ta slovenski standard je istoveten z: prEN 14178-1
ICS:
81.040.20 Steklo v gradbeništvu Glass in building
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2017
ICS 81.040.20 Will supersede EN 14178-1:2004
English Version
Glass in building - Basic alkaline earth silicate glass
products - Part 1: Float glass
Verre dans la construction - Verre de silicate Glas im Bauwesen - Basiserzeugnisse aus Erdalkali-
alcalinoterreux de base - Partie 1 : Glace flottée Silikatglas - Teil 1: Floatglas
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-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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey 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

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 14178-1:2017 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Chemical composition . 6
4.1 Principal constituents . 6
4.2 Tint . 7
5 Physical and mechanical characteristics . 7
5.1 General characteristics . 7
5.2 Characteristic bending strength . 7
5.3 Designation of clear basic alkaline earth silicate glass . 7
5.3.1 General . 7
5.3.2 Clear transparent basic alkaline earth silicate glass . 8
5.4 Stability of physical and chemical characteristics . 8
6 Dimensional requirements. 9
6.1 Thickness . 9
6.1.1 General . 9
6.1.2 Tolerances . 9
6.2 Length, width and squareness . 9
7 Quality requirements . 10
7.1 General . 10
7.2 Methods of observation and measurement . 10
7.2.1 Optical faults . 10
7.2.2 Visual faults . 12
7.3 Acceptance levels . 12
7.3.1 Optical faults . 12
7.3.2 Spot faults . 12
7.3.3 Linear/extended faults . 13
8 Designation. 13
Annex A (normative) Method for measuring spot fault size (including halo) . 14
A.1 Conditions of observation . 14
A.2 Measurement of the size of the spot fault including the halo. 15
Annex B (informative) Complementary information related to REACH . 17
Bibliography . 18
European foreword
This document (prEN 14178-1:2017) 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 will supersede EN 14178-1:2004.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
This European standard consists of the following parts:
— prEN 14178-1: Glass in building — Basic alkaline earth silicate glass — Part 1: Float glass;
— prEN 14178-2: Glass in building — Basic alkaline earth silicate glass — Part 2: Product standard.
This European standard differs from EN 14178-1:2004 as follows:
a) chemical composition has been modified in Table 1;
b) dimension, observation methods and defect tolerances have been modified in adequation with
EN 572-2 and −8 standards;
c) a new informative Annex B given complementary information related to REACH has been added;
d) the document has been editorially revised.
1 Scope
This European standard specifies and classifies basic alkaline earth silicate glass products for use in
building. It indicates their chemical composition, main physical and mechanical properties, dimensional
and minimum quality requirements (in respect of optical and visual faults).
This European standard applies to basic alkaline earth silicate glass supplied in jumbo sizes, split sizes,
supplied sizes or in 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 m .
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 410, Glass in building — Determination of luminous and solar characteristics of glazing
ISO 9385, Glass and glass-ceramics — Knoop hardness test
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
basic alkaline earth silicate float glass
flat, transparent, clear or tinted float glass with a chemical composition according to 4.1 of this
document, having parallel and polished faces obtained by continuous casting and floatation on a metal
bath
3.2
length, H and width, B
defined with reference to the direction of draw of the glass ribbon as shown in Figure 1
Key
1 ––- > direction of draw
H length
B width
Figure 1 — Relationship between length, width and direction of draw
3.3
jumbo sizes
glass delivered in the following sizes:
— nominal length H: 4 500 mm, 5 100 mm or 6 000 mm;
— nominal width B: 3 210 mm
Note 1 to entry: The usual width is 3 210 mm. Exceptional production requirements may cause this to be
reduced but the nominal width is never below 3 150 mm.
3.4
split sizes
glass delivered in the following size ranges:
— nominal length H: 1 000 mm to 2 550 mm;
— nominal width B: 3 210 mm
Note 1 to entry: The usual width is 3 210 mm. Exceptional production requirements may cause this to be
reduced but the nominal width is never below 3 150 mm.
3.5
optical fault
fault which lead to distortions on the appearance of objects observed through the glass
3.6
visual fault
fault which alter the visual quality of the glass
Note 1 to entry: Visual faults include spot faults and linear / extended faults.
3.7
spot fault
nucleus which is generally accompanied by a halo of distorted glass
Note 1 to entry: Spot fault can be solid inclusions, bubbles, etc.
3.8
halo
area locally distorted, generally around a point defect
3.9
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
4 Chemical composition
4.1 Principal constituents
The basic glass products covered by this European standard are all manufactured from basic alkaline
earth silicate glass.
The magnitude of the proportions by mass of the constituents of basic alkaline earth silicate glass
covered by this standard is given in Table 1, see also Annex B.
NOTE Oxygen is not mentioned in Table 1 (see Annex A).
Table 1 — Magnitude of the proportions by mass of the constituents of basic alkaline earth
silicate glass
Proportion by mass of element
Constituents
[%]
Silicon (Si) 25,7 to 32,8
Calcium (Ca) 2,1 to 8,6
Potassium (K) 4,1 to 11,7
Aluminium (Al) 0 to 8,0
Zirconium (Zr) 0 to 6,0
Strontium (Sr) + Barium (Ba) 0,8 to 13,2
Other components excluding
< 5
a
oxygen
a
Properties other than photometric characteristics shall not be significantly
altered by these other components.
4.2 Tint
Body tinted basic alkaline earth silicate glass is obtained by the addition of suitable materials.
5 Physical and mechanical characteristics
5.1 General characteristics
Conventional numerical values for the physical and mechanical characteristics of basic alkaline earth
silicate glass excluding ‘Characteristic bending strength’ (f ) are given in Table 2. These values, for
g,k
normal annealed basic alkaline earth silicate glass without any further toughening, are not precise
requirements with which the glass shall strictly comply, but are the generally accepted figures for use in
calculations where a high degree of accuracy is not required.
Table 2 — Physical and mechanical characteristics of basic alkaline earth silicate glass
Characteristic Symbol Value and unit
Density (at 18 °C) ρ 2 700 kg/m
Hardness (Knoop) HK a
0,1/20
5 GPa to 6 GPa
Young's modulus (modulus of elasticity) E 7,7 × 10 Pa
Poisson's ratio μ 0,2
Specific heat capacity c 0,7 × 10 J/(kg·K)
p
−6
Nominal value of average coefficient of linear expansion α 8 × 10 /K
between 20 °C and 300 °C
Resistance against temperature differential and sudden b
40 K
temperature change
Thermal conductivity λ 0,8 W/(m·K) to 1,1 W/(m·K)
Mean refractive index to visible radiation (380 nm to n 1,5
780 nm)
Emissivity (corrected) ε 0,837
a
Knoop Hardness in accordance with ISO 9385.
b
Generally accepted value that is influenced by edge quality.
5.2 Characteristic bending strength
The
...