Foreword

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This document was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 4, Products (other than hoses), in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 249, Plastics, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This third edition cancels and replaces the second edition (ISO 3386-1:1986), which has been revised. It also incorporates the Amendment ISO 3386-1:1986/Amd 1:2010.

The main changes are as follows:

revision of the text in the Scope, Clause 2 and 3;
addition of a schematic representation of the test procedure in Clause 6;

A list of all parts in the ISO 3386 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

The compression stress/strain characteristics is a measure of the load-bearing properties of the material, though not necessarily of its capacity to sustain a long-term load.

The compression stress/strain characteristics differs from the indentation hardness characteristics (as determined in accordance with ISO 2439), which are known to be influenced by the thickness and the tensile properties of the flexible cellular material under test, by the shape of the compression plate and by the shape and size of the test piece.

This document specifies a method for low-density materials and differs from part 2 in the following ways:

It is mainly concerned with materials of density up to 250 kg/m3;
Requires a compression stress value for a compression of 40%;
It permits the use of a cylindrical test piece.

1 Scope

This document specifies a method for the determination of the compression stress/strain characteristics of low-density flexible cellular materials up to 250 kg/m³. It also specifies a method for the calculation of the compression stress value of such materials.

2 Normative references

3 Terms and definitions

4 Apparatus

4.1 Test machine

4.2 Supporting surface

4.3 Compression plate

5 Test piece

5.1 Form and dimensions

5.2 Samples showing orientation

5.3 Number of test pieces

5.4 Conditioning

6 Procedure

7 Expression of results

7.1 Compression stress/strain characteristic

7.2 Compression stress value

8 Repeat tests

9 Test report

Bibliography

ISO 3386-1:2025

Polymeric materials, cellular flexible. Determination of stress-strain characteristics in compression — - Part 1: Low-density materials

Current

Published:

14 Jul 2025