SIST IEC 60839-2-3:1995

Alarm systems. Part 2: Requirements for intruder alarm systems. Section Three: Requirements for infrared-beam interruption detectors in buildings

Specifies requirements and test procedures for infrared beam interruption detectors for use in intruder alarm systems installed in buildings.

Systèmes d'alarme. Deuxième partie: Prescriptions pour les systèmes d'alarme anti-intrusion. Section trois: Prescriptions pour les détecteurs à interruption de faisceaux infrarouges dans les bâtiments

Définit les prescriptions spécifiques et les modalités d'essai relatives aux détecteurs à interruption de faisceaux infrarouges utilisés dans les systèmes d'alarme anti-intrusion installés dans les bâtiments.

Alarm systems - Part 2: Requirements for intruder alarm systems - Section Three: Requirements for infrared beam interruption detectors in buildings

General Information

• Status: Published
• Publication Date: 31-Aug-1995
• ICS: 13.320 - Alarm and warning systems
• Technical Committee: EAL - Alarm systems
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Sep-1995
• Due Date: 01-Sep-1995
• Completion Date: 01-Sep-1995
• Ref Project: IEC 60811-501:2012 - Electric and optical fibre cables - Test methods for non-metallic materials - Part 501: Mechanical tests - Tests for determining the mechanical properties of insulating and sheathing compounds

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Alarm systems - Part 2: Requirements for intruder alarm systems - Section Three: Requirements for infrared beam interruption detectors in buildingsSystèmes d'alarme. Deuxième partie: Prescriptions pour les systèmes d'alarme anti-intrusion. Section trois: Prescriptions pour les détecteurs à interruption de faisceaux infrarouges dans les bâtimentsAlarm systems. Part 2: Requirements for intruder alarm systems. Section Three: Requirements for infrared-beam interruption detectors in buildings13.320Alarmni in opozorilni sistemiAlarm and warning systemsICS:Ta slovenski standard je istoveten z:IEC 60839-2-3SIST IEC 60839-2-3:1995en01-september-1995SIST IEC 60839-2-3:1995SLOVENSKI
STANDARD



SIST IEC 60839-2-3:1995



NORMECEIINTERNATIONALEIECINTERNATIONAL60839-2-3STANDARDSystèmes d'alarmePartie 2:Prescriptions pour les systèmes d'alarmeanti-intrusionSection trois – Prescriptions pour les détecteursà interruption de faisceaux infrarouges dans lesbâtimentsAlarm systemsPart 2:Requirements for intruder alarm systemsSection Three – Requirements for infrared-beaminterruption detectors in buildings© IEC 1987 Droits de reproduction réservés — Copyright - all rights reservedPremière éditionFirst edition1987-12Aucune partie de cette publication ne peut être reproduite niutilisée sous quelque forme que ce soit et par aucunprocédé, électronique ou mécanique, y compris la photo-copie et les microfilms, sans raccord écrit de l'éditeur.No part of this publication may be reproduced or utilized inany form or by any means, electronic or mechanical,including photocopying and microfilm, without permission inwriting from the publisher.International Electrotechnical Commission3, rue de Varembé Geneva, SwitzerlandTelefax: [phone]e-mail: [e-mail] web site http: //www.iec.chIEC•Commission Electrotechnique InternationaleInternational Electrotechnical CommissionMemAyHapoiaHari 3nenrporexHH4ecnaa HOMHCCHH•CODE PRIXPRICE CODEPour prix, voir catalogue en vigueurFor price, see current catalogueSIST IEC 60839-2-3:1995



839-2-3 (1) © IEC- 3 -CONTENTSPageFOREWORD 5PREFACE 5Clause1.Scope 72.Object 73.Reference document 74.Definitions 95.General considerations96.Requirements 97.Test procedures 13SIST IEC 60839-2-3:1995



839-2-3 (1) © IEC- 5 -INTERNATIONAL ELECTROTECHNICAL COMMISSIONALARM SYSTEMSPart 2: Requirements for intruder alarm systems Section Three - Requirements for infrared-beaminterruption detectors in buildingsFOREWORD1)The formal decisions or agreements of the IEC on technical matters, prepared by TechnicalCommittees on which all the National Committees having a special interest therein arerepresented, express, as nearly as possible, an international consensus of opinion on thesubjects dealt with.2)They have the form of recommendations for international use and they are accepted by theNational Committees in that sense.3)In order to promote international unification, the IEC expresses the wish that allNational Committees should adopt the text of the IEC recommendation for their nationalrules in so far as national conditions will permit. Any divergence between the IEC recom-mendation and the corresponding national rules should, as far as possible, be clearlyindicated in the latter.PREFACEThis standard has been prepared by IEC Technical Committee No. 79:Alarm Systems.The text of this standard is based on the following documents:Six Months' RuleReport on Voting79(C0)779(C0)13Full information on the voting for the approval of this standard can befound in the Voting Report indicated in the above table.SIST IEC 60839-2-3:1995



839-2-3 (1) © IEC- 7 -ALARM SYSTEMSPart 2: Requirements for intruder alarm systemsSection Three - Requirements for infrared-beaminterruption detectors in buildings 1.ScopeThis standard specifies the specific requirements and test proceduresfor infrared-beam interruption detectors to be used in intruder alarmsystems installed in buildings.This standard shall be used in conjunction with the following IECPublications:839-2-2 (1987): Alarm systems, Part 2: Requirements for intruderalarm systems. Section Two - Requirements fordetectors - General.This publication specifies the general requirements for detectors foruse in intruder alarm systems installed in buildings.Publication 839-2-3 therefore supplements the general requirementsfor intruder alarm systems of Publication 839-2-2.839-1-1: Part 1: General requirements. Section One - General. (Underconsideration.)This publication specifies the general requirements for alarmsystems.2.Object The object of this standard is to specify those requirements forinfrared-beam interruption detectors which will ensure that they willperform satisfactorily, minimize false alarms and be compati
...

IEC 60811-501
®

Edition 1.0 2012-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Electric and optical fibre cables – Test methods for non-metallic materials –
Part 501: Mechanical tests – Tests for determining the mechanical properties
of insulating and sheathing compounds

Câbles électriques et à fibres optiques – Méthodes d’essai pour les matériaux
non-métalliques –
Partie 501: Essais mécaniques – Détermination des propriétés mécaniques
des mélanges pour les enveloppes isolantes et les gaines

IEC 60811-501:2012

---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
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All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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---------------------- Page: 2 ----------------------
IEC 60811-501

®


Edition 1.0 2012-03




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Electric and optical fibre cables – Test methods for non-metallic materials –

Part 501: Mechanical tests – Tests for determining the mechanical properties

of insulating and sheathing compounds




Câbles électriques et à fibres optiques – Méthodes d’essai pour les matériaux

non-métalliques –


Partie 501: Essais mécaniques – Détermination des propriétés mécaniques

des mélanges pour les enveloppes isolantes et les gaines












INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE

PRICE CODE
INTERNATIONALE

CODE PRIX Q


ICS 29.035.01; 29.060.20 ISBN 978-2-88912-975-1



Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 3 ----------------------
– 2 – 60811-501  IEC:2012
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Test method . 7
4.1 General . 7
4.2 Insulation . 7
4.2.1 General . 7
4.2.2 Sampling . 7
4.2.3 Preparation and conditioning of test pieces . 7
4.2.4 Determination of cross-sectional area . 9
4.2.5 Ageing treatment . 11
4.2.6 Tensile testing procedure . 11
4.2.7 Expression of results . 11
4.3 Sheath . 12
4.3.1 General . 12
4.3.2 Sampling . 12
4.3.3 Preparation and conditioning of test pieces . 12
4.3.4 Determination of cross-sectional area . 12
4.3.5 Ageing treatment . 13
4.3.6 Tensile testing procedure . 13
4.3.7 Expression of results . 13
5 Test report. 13
Annex A (informative) Principle of operation of a typical machine for preparing test
pieces . 16
Bibliography . 17

Figure 1 – Dumb-bell test piece . 14
Figure 2 – Small dumb-bell test piece . 14
Figure 3 – Punch end showing groove . 14
Figure 4 – Test pieces cut by grooved punch . 15
Figure A.1 – Machine for preparing test pieces . 16

---------------------- Page: 4 ----------------------
60811-501  IEC:2012 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ELECTRIC AND OPTICAL FIBRE CABLES –
TEST METHODS FOR NON-METALLIC MATERIALS –

Part 501: Mechanical tests –
Tests for determining the mechanical properties
of insulating and sheathing compounds


FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60811-501 has been prepared by IEC technical committee 20:
Electric cables.
This Part 501 of IEC 60811 cancels and replaces Clause 9 of IEC 60811-1-1:1993, which is
withdrawn. Full details of the replacements are shown in Annex A of IEC 60811-100:2012.
There is one significant technical change with respect to the previous edition:
– the requirements for the (minimum) thickness of dumb-bell test pieces have changed.
See also the Foreword to IEC 60811-100.

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– 4 – 60811-501  IEC:2012
The text of this standard is based on the following documents:
FDIS Report on voting
20/1297/FDIS 20/1346/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
This part of IEC 60811 shall be used in conjunction with IEC 60811-100.
A list of all the parts in the IEC 60811 series, published under the general title Electric and
optical fibre cables – Test methods for non-metallic materials, can be found on the IEC
website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

---------------------- Page: 6 ----------------------
60811-501  IEC:2012 – 5 –
INTRODUCTION
The IEC 60811 series specifies the test methods to be used for testing non-metallic materials
of all types of cables. These test methods are intended to be referenced in standards for
cable construction and for cable materials.
NOTE 1 Non-metallic materials are typically used for insulating, sheathing, bedding, filling or taping within cables.
NOTE 2 These test methods are accepted as basic and fundamental and have been developed and used over
many years principally for the materials in all energy cables. They have also been widely accepted and used for
other cables, in particular optical fibre cables, communication and control cables and cables for ships and offshore
applications.

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– 6 – 60811-501  IEC:2012
ELECTRIC AND OPTICAL FIBRE CABLES –
TEST METHODS FOR NON-METALLIC MATERIALS –

Part 501: Mechanical tests –
Tests for determining the mechanical properties
of insulating and sheathing compounds



1 Scope
This Part 501 of IEC 60811 gives the procedure for determining the mechanical properties,
which typically applies to cross-linked and thermoplastic compounds used for insulating and
sheathing materials.
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.
IEC 60811-100:2012, Electric and optical fibre cables – Test methods for non-metallic
materials – Part 100: General
IEC 60811-201, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 201: General tests – Measurement of insulation thickness
IEC 60811-202, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 202: General tests – Measurement of thickness of non-metallic sheaths
IEC 60811-203, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 203: General tests – Measurement of overall dimensions
IEC 60811-401, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 401: Miscellaneous tests – Thermal ageing methods – Ageing in an air oven
IEC 60811-404, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 404: Miscellaneous tests – Mineral oil immersion tests for sheaths made with cross-
linked compounds
IEC 60811-606, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 606: Physical tests – Methods for determining the density
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60811-100, together
with the following, apply.
3.1
maximum tensile force
highest value reached by the load during the test

---------------------- Page: 8 ----------------------
60811-501  IEC:2012 – 7 –
3.2
tensile stress
tensile force per unit of the cross-sectional area of the unstretched test piece
3.3
tensile strength
maximum tensile stress recorded in extending the test piece to breaking point
3.4
elongation at break
increase of the length between the reference marks of the test piece, expressed as the
percentage of the length between the reference marks of the unstretched test piece at
breaking point
4 Test method
4.1 General
This part of IEC 60811 shall be used in conjunction with IEC 60811-100.
Unless otherwise specified, before any test, all test pieces, aged and unaged, shall be kept
for at least 3 h at a temperature of (23 ± 5) °C.
4.2 Insulation
4.2.1 General
These tests are to determine the tensile strength and elongation at break of the insulating
material (exclusive of any semi-conducting layers) of the cable in the condition as
manufactured (i.e. without any ageing treatment) and, when required, after one or more
accelerated ageing treatment(s), which are prescribed in the relevant cable standard.
When the ageing treatment is to be carried out on prepared test pieces (in accordance
with IEC 60811-401), the test pieces for the ageing treatment shall be from positions adjacent
to the test pieces used for the test without ageing and the tensile tests on the aged and
unaged test pieces shall be made in immediate succession.
NOTE Where further increased test reliability is necessary, it is recommended that the tests on aged and unaged
test pieces are performed by the same person using the same testing method and the same apparatus, in the same
laboratory.
4.2.2 Sampling
One sample of each core to be tested (or of the insulation from each core to be tested) shall
be taken of sufficient size to provide a minimum of five test pieces each for the tensile tests
without ageing and the tensile tests after each of the required ageing treatments, bearing in
mind that a 100 mm length is needed for the preparation of each test piece.
The cores of unsheathed flat cables shall not be separated.
Any sample that shows signs of mechanical damage shall not be used for the test.
4.2.3 Preparation and conditioning of test pieces
a) Conditioning of test pieces shall be carried out as follows:
1) Elevated temperature conditioning
NOTE 1 Elevated temperature conditioning is not an ageing treatment. It is used as a means of ensuring
stable and consistent test pieces when required. It is used a) when called for in the relevant cable
standard, or b) if there is a doubt or disagreement about a result and the test needs to be repeated. In

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– 8 – 60811-501  IEC:2012
either case, the conditioning applies only to the test piece as taken from the cable before any subsequent
treatment (ageing, compatibility test, oil immersion etc).
Where conditioning at elevated temperature is used, such conditioning shall be carried
out as follows:
– for dumb-bells,
(A) after the removal of the insulation from the cable and removal of semi-
conducting layers (if any) but before the cutting of strips;
(B) after grinding (or cutting) to obtain parallel surfaces.
Where grinding (or cutting) is not needed, the conditioning shall be performed at
the point in the test protocol according to (A);
– for tubular test pieces, such conditioning shall be carried out after removal of the
conductor, and any separator, but before applying the reference marks, if any, for
measurement of the extension.
Where the relevant cable standard calls for conditioning at elevated temperature, it
shall be for the time and temperature given in that standard. Where, in case of doubt,
the test has to be repeated, the conditioning shall be 24 h at (70 ± 2) °C, or a lower
temperature corresponding to the maximum operating temperature of the conductor.
2) Room temperature conditioning
Before determination of the cross-sectional area, all test pieces shall be protected from
direct sunlight and maintained for at least 3 h at a temperature of (23 ± 5) °C, except
for thermoplastic insulating materials which shall be kept at (23 ± 2) °C.
b) Dumb-bell test pieces
Dumb-bell test pieces shall be used whenever possible. They shall be prepared from
samples of insulation removed from the conductor, cut open in the direction of the axis of
the core.
Semi-conducting layers, if any, inside and/or outside the insulation, shall be removed
mechanically, i.e. without using a solvent.
Each sample of insulation shall be cut into strips of an appropriate length. The strips shall
be marked to identify the sample from which they are cut and their positions relative to
each other in the original sample.
The strips of insulation shall be ground or cut, so as to obtain two parallel smooth surfaces
between the reference marks mentioned below, care being taken to avoid undue heating. An
example of a cutting machine is given in Annex A. For polyethylene (PE) and polypropylene
(PP) insulation, cutting only, not grinding, shall be employed. After cutting or grinding,
including any removal of burrs, the thickness of the strips shall not be less than 0,8 mm and
not more than 2,0 mm. If it is not possible to prepare dumb-bell test pieces that comply with
the minimum thickness of 0,8 mm, then tubular test pieces shall be used. If tubular test pieces
cannot be prepared, then dumb-bells thinner than 0,8 mm may be used, but the rate of
separation shall be 25 mm/min.
NOTE 2 The test report should also include the fact that non-compliant dumb-bells were used and that the result
is indicative.
NOTE 3 For certain tests, a minimum thickness may be required, for instance for the ozone resistance test
(IEC 60811-403) and the mineral oil immersion test (IEC 60811-404).
A dumb-bell test piece, in accordance with Figure 1, shall then be punched from each
prepared strip of insulation, or if possible, two dumb-bell test pieces shall be punched side
by side.
In order to improve the reliability of the results, the following is recommended:
– the punch shall be very sharp to minimize imperfections in the test piece;
– a cardboard or other suitable support shall be placed between the strip and the base
plate. This support shall be marked during punching, but not completely cut through by
the punch;
– burrs on the sides of the test piece shall be avoided.

---------------------- Page: 10 ----------------------
60811-501  IEC:2012 – 9 –
For materials where punching results in burrs, the following method may be used:
1) each end of the punch shall have a groove approximately 2,5 mm wide and 2,5 mm
high (see Figure 3);
2) the cut dumb-bell test pieces shall remain attached at both ends with the strip
previously prepared according to the requirements of 4.2.3 b) (see Figure 4);
3) with the machine given in Annex A, an additional 0,10 mm to 0,15 mm thickness can
be cut away to remove possible burrs resulting from the dumb-bell punch. When this
operation is completed, the dumb-bell test pieces shall be cut through at their ends in
order to remove them from the strip.
When the diameter of the core is too small to allow the dumb-bell to be cut in accordance
with Figure 1, then a smaller dumb bell test piece in accordance with Figure 2, shall be
punched from each prepared strip.
The central 20 mm for the larger dumb-bells or 10 mm for the smaller dumb-bells shall be
marked on each test piece, immediately before the tensile test.
NOTE 4 Where a contact extensometer is used, the pre set grips at the required spacing are deemed to
constitute a mark.
Dumb-bell test pieces with incomplete ends are permitted, provided that the breaking point
occurs between the reference marks.
c) Tubular test pieces
Tubular test pieces shall be used only when the dimensions of the core are such that it is
not possible to prepare dumb-bell test pieces.
The samples of core shall be cut into pieces approximately 100 mm long and the
conductor and any outer coverings removed, care being taken not to damage the insu-
lation. The tubes shall be marked to identify the sample from which they were prepared
and their relative positions in the sample.
Careful removal of the conductor can be facilitated by the use of one or more of the
following operations:
1) by elongation of the rigid conductors;
2) by careful rolling of the core under low mechanical force;
3) in the case of stranded or flexible conductors, by first removing one or more of the
central strands or wires.
After removal of the conductor, the separators, if any, are removed. In case of difficulty,
one of the following operations may be used:
– immersion in water, in the case of paper separators;
– immersion in ethyl alcohol, in the case of polyethylene terephthalate separators;
– rolling of the insulation on a smooth surface.
The central 20 mm shall be marked immediately before the tensile test.
NOTE 5 Where a contact extensometer is used, the pre set grips at the required spacing are deemed to constitute
a mark.
The presence of pieces of separator remaining inside the test piece can be observed during
the tensile tests by formation of irregularities in the test piece during elongation.
In such cases, the result shall be rejected.
4.2.4 Determination of cross-sectional area
a) Dumb-bell test piece
The cross-sectional area of each test piece is the product of the common width and the
measured individual minimum thickness which shall be determined as follows.
For the width:

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– 10 – 60811-501  IEC:2012
– the common width is the minimum width of three, randomly selected test pieces;
– if there is doubt about the uniformity of the width, this shall be measured at three
positions on the top and the bottom side of the three test pieces. The mean of the
top and bottom side measurements shall be calculated for each position. The
common width shall be the minimum of the nine mean values determined on the
three test pieces;
– in the case of further doubt, the width is measured on each individual test piece.
For the thickness:
– the thickness of each test piece is the minimum of three thickness measurements
carried out in the area to be stretched.
The measurements shall be carried out by an optical instrument or by a dial gauge
2
giving a contact pressure not exceeding 0,07 N/mm .
The instrument shall be capable of measuring the thickness with an error of not more
than 0,01 mm and the width with an error of not more than 0,04 mm.
In case of doubt, where technically possible, an optical instrument shall be used.
2
Alternatively, a dial gauge with a maximum contact pressure of 0,02 N/mm may be
used.
NOTE An appropriate curved foot of the dial gauge should be used if the central part of the dumb-bell is
still curved.
b) Tubular test piece
In the middle of the sample being used to prepare the test pieces, a piece shall be taken
to determine the cross-sectional area, A, in square millimetres, of the test piece, using
one of the following methods. In case of doubt, the second method b2) shall be used.
b1) From the dimensions, using the formula:
A = π (D – δ) δ
where
δ is the mean value of the thickness of the insulation, in millimetres, determined
as specified in IEC 60811-201 and rounded off to two decimal places;
D is the mean value of the outer diameter of the test piece, in millimetres,
determined as specified in test method of IEC 60811-203 and rounded off to
two decimal places.
b2) From the density, the mass and the length, using the formula:
1 000 m
A =
d × l
where
m is the mass of the test piece, in grams, to three decimal
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