EN ISO 844:2014

SLOVENSKI STANDARD
01-oktober-2014
1DGRPHãþD
SIST EN ISO 844:2009
Penjeni polimerni materiali - Trde pene - Ugotavljanje lastnosti stiskanja (ISO
844:2014)
Rigid cellular plastics - Determination of compression properties (ISO 844:2014)
Harte Schaumstoffe - Bestimmung der Druckeigenschaften (ISO 844:2014)
Plastiques alvéolaires rigides - Détermination des caractéristiques de compression (ISO
844:2014)
Ta slovenski standard je istoveten z: EN ISO 844:2014
ICS:
83.100 Penjeni polimeri Cellular materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 844
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2014
ICS 83.100 Supersedes EN ISO 844:2009
English Version
Rigid cellular plastics - Determination of compression properties
(ISO 844:2014)
Plastiques alvéolaires rigides - Détermination des Harte Schaumstoffe - Bestimmung der Druckeigenschaften
caractéristiques de compression (ISO 844:2014) (ISO 844:2014)
This European Standard was approved by CEN on 7 July 2014.

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
© 2014 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 844:2014 E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
This document (EN ISO 844:2014) has been prepared by Technical Committee ISO/TC 61 “Plastics” in
collaboration with Technical Committee CEN/TC 249 “Plastics” 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 February 2015, and conflicting national standards shall be withdrawn
at the latest by February 2015.
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 supersedes EN ISO 844:2009.
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, 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.
Endorsement notice
The text of ISO 844:2014 has been approved by CEN as EN ISO 844:2014 without any modification.

INTERNATIONAL ISO
STANDARD 844
Sixth edition
2014-08-01
Rigid cellular plastics —
Determination of compression
properties
Plastiques alvéolaires rigides — Détermination des caractéristiques
de compression
Reference number
ISO 844:2014(E)
©
ISO 2014
ISO 844:2014(E)
© ISO 2014
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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Published in Switzerland
ii © ISO 2014 – All rights reserved

ISO 844:2014(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 2
5 Principle . 2
6 Apparatus . 2
6.1 Compression-testing machine . 2
6.2 Devices for measuring displacement and force . 3
6.3 Instruments for measuring the dimensions of the test specimens . 3
7 Test specimens. 3
7.1 Dimensions . 3
7.2 Preparation . 4
7.3 Number . 4
7.4 Conditioning . 4
8 Procedure. 4
9 Expression of results . 5
9.1 General . 5
9.2 Compressive strength and corresponding relative deformation . 6
9.3 Compressive stress at 10 % relative deformation . 7
9.4 Compressive modulus of elasticity . 7
10 Precision . 8
11 Test report . 8
Bibliography .10
ISO 844:2014(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any
patent rights identified during the development of the document will be in the Introduction and/or on
the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 61, Plastics, Subcommittee SC 10, Cellular plastics.
This sixth edition cancels and replaces the fifth edition (ISO 844:2007), which has been technically
revised to specify the choice of the procedure for the determination of the compressive strength and
corresponding relative deformation, the compressive stress at 10 % relative deformation and the
compressive modulus of rigid cellular plastics.
iv © ISO 2014 – All rights reserved

INTERNATIONAL STANDARD ISO 844:2014(E)
Rigid cellular plastics — Determination of compression
properties
1 Scope
This International Standard specifies a method of determining:
a) the compressive strength and corresponding relative deformation,
or
b) the compressive stress at 10 % relative deformation,
and
c) when desired, the compressive modulus of rigid cellular plastics.
There are two procedures:
— Procedure A employs crosshead motion for determination of compressive properties. Procedure A
is intended to be used when compressive stress at 10 % relative deformation has to be determined.
— Procedure B employs strain measuring devices mounted on the specimen (contact extensometer)
or similar device which measures directly sample deformation. Procedure B is intended to be used
when compressive modulus has to be determined.
NOTE Compressive strength (at maximum load) can be determined either with Procedure A and B.
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.
ISO 1923, Cellular plastics and rubbers — Determination of linear dimensions
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
relative deformation
ε
ratio of the reduction (in relation to its initial value) in thickness of the test specimen (Procedure A) or
of extensometer gauge length (Procedure B)
Note 1 to entry: It is expressed as a percentage.
Note 2 to entry: ε is the relative deformation corresponding to σ (see 3.2).
m m
3.2
compressive strength
σ
m
maximum compressive force F divided by the initial cross-sectional area of
...