ISO 12808:2024

International
Standard
ISO 12808
First edition
Hardware for furniture — Strength
2024-03
and durability of extension
elements and their components
Quincaillerie d'ameublement — Résistance mécanique et
endurance des éléments extractibles et de leurs composants
Reference number
© ISO 2024
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test conditions . 2
4.1 General .2
4.2 Application of forces .2
4.3 Tolerances .2
4.4 Sequence of testing .3
4.5 Inspection and assessment of results .3
5 Test equipment . 3
5.1 General .3
5.2 Masses .3
5.3 Glass/steel marbles .3
5.4 Loads for filing pockets .3
5.5 Loading pad .4
5.6 Test frame and test drawer .5
5.7 Particle board properties.6
6 Test procedures and requirements . 6
6.1 General .6
6.2 Overload tests . .6
6.2.1 General .6
6.2.2 Vertical downwards static overload .6
6.2.3 Horizontal sideways static overload.7
6.2.4 Outwards static overload .7
6.2.5 Slam-shut/open .8
6.3 Functional tests .8
6.3.1 General .8
6.3.2 Deflection of extension element bottoms .8
6.3.3 Deformation of front and back .9
6.3.4 Operating forces .9
6.3.5 First vertical downwards static load test .10
6.3.6 First horizontal sideways static load .10
6.3.7 Determination of reference point for the deflection of front.10
6.3.8 Durability .11
6.3.9 Deflection of front . 12
6.3.10 Second vertical downwards static load . 12
6.3.11 Second horizontal sideways static load . 12
6.3.12 Operating forces . 12
6.3.13 Slam-shut/open . 13
6.4 Corrosion resistance . 13
6.5 Test report . 13
Annex A (normative) Product information system . 14
Annex B (normative) Test method: Slam-shut/open of extension elements .15
Annex C (normative) Test parameters .18

iii
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
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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 document should be noted. This document was drafted in accordance with the editorial rules of the
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This document was prepared by Technical Committee ISO/TC 136, Furniture.
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.

iv
Introduction
The aim of this document is to provide furniture manufacturers, designers and developers with comparable
information regarding the performance of extension elements and drawers.
The tests consist of the application of loads, forces and velocities simulating normal functional use, as well
as misuse, that can reasonably be expected to occur.
With the exception of the corrosion test in 6.4, the tests are designed to evaluate properties without regard
to materials, design/construction or manufacturing processes.
The strength and durability tests only relate to the extension elements and the parts used for the attachment,
e.g. screws.
The strength and durability tests are carried out in a test frame with specified properties. The test results
can only be used as a guide to the performance of a piece of furniture.
The test results are only valid for the extension element tested. These results can be used to represent the
performance of production models provided that the tested model is representative of the production model.

v
International Standard ISO 12808:2024(en)
Hardware for furniture — Strength and durability of
extension elements and their components
1 Scope
This document specifies test methods and requirements for the strength and durability of all types of
extension elements and their components for all fields of application, except table extensions.
With the exception of corrosion, ageing and the influence of heat and humidity are not covered in this
document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements 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.
ISO 6270-2, Paints and varnishes — Determination of resistance to humidity — Part 2: Condensation (in-cabinet
exposure with heated water reservoir)
ISO 9427, Wood-based panels — Determination of density
ISO 10289, Methods for corrosion testing of metallic and other inorganic coatings on metallic substrates —
Rating of test specimens and manufactured articles subjected to corrosion tests
EN 320, Particleboards and fibreboards — Determination of resistance to axial withdrawal of screws
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
catch device
device which keeps or pulls an extension element (3.2) in place, but does not require a second action in order
to release it
EXAMPLE A magnetic catch or a self-closing or self-opening mechanism.
3.2
extension element
component that can be pulled out and pushed in
EXAMPLE Drawers, suspended pocket files, keyboard trays.

3.3
loading capacity
total mass
M
mass, as specified by the manufacturer, for which the extension element (3.2) fulfils the strength and
durability requirements
Note 1 to entry: The load capacity is expressed in kg.
Note 2 to entry: The loading capacity includes the extension element and the load in/on the extension element.
3.4
damper
mechanism which gently brings the extension element (3.2) to a stop
4 Test conditions
4.1 General
The extension element shall be assembled/mounted in accordance with the instructions supplied with it.
If mounting or assembly instructions are not supplied, the most adverse configuration shall be used and
the mounting or assembly method shall be recorded in the test report. Fittings shall be tightened before
testing and shall not be re-tightened unless specifically required in the manufacturer’s instructions. If the
configuration must be changed to produce the worst-case conditions, this shall be recorded in the test report.
For testing a range of related extension elements, only worst case(s) need to be tested.
The tests shall be carried out in indoor ambient conditions at a temperature between 15 °C and 27 °C. If
during a test the temperature is outside of the range of 15 °C to 27 °C, the maximum and/or minimum
temperature shall be recorded in the test report.
Extension elements which include structural hardware parts made of hygroscopic plastic materials, for
example, polyamide, shall be conditioned at (23 ± 2) °C and a relative humidity of (50 ± 5) % for at least 7 d
before testing.
In the case of designs not addressed in the test procedures, the test shall be carried out as far as possible as
described, and deviations from the test procedure recorded in the test report.
Before beginning the testing, visually inspect the extension element thoroughly. Record any defects so that
they are not assumed to have been caused by the tests. Carry out measurements when specified.
4.2 Application of forces
The forces in the static load tests shall be applied sufficiently slowly to ensure that negligible dynamic force
is applied. Unless otherwise specified, each force shall be maintained for not less than 10 s and not more
than 15 s.
The forces in durability tests shall be applied at a rate to ensure that excessive heating does not occur.
The forces may be replaced by masses. The relation 10 N = 1 kg may be used for this purpose.
4.3 Tolerances
Unless otherwise stated, the following tolerances are applicable:
— forces: ±5 % of the nominal force;
— velocities: ±5 % of the nominal velocity;
— masses: ±1 % of the nominal mass;

— dimensions: ±1 mm of the nominal dimension;
— angles: ±2° of the nominal angle.
The accuracy for the positioning of loading pads shall be ±5 mm.
4.4 Sequence of testing
The tests shall be carried out in the same sequence as the clauses are numbered in this document. If the
clause sequence is not followed, the sequence shall be recorded in the test report.
4.5 Inspection and assessment of results
Before and after completion of each test, carry out the inspection as specified, after using adjustment
devices, if available.
Before any measurements are taken, the loaded extension shall be moved 10 times over the total
extension length.
Record any changes that have taken place since the initial inspection. The inspection shall include at least
the following:
a) the fracture of any component or joint;
b) the loosening of any joint intended to be rigid, which can be demonstrated by hand pressure;
c) the deformation or wear of any part or component such that its functioning is impaired;
d) the loosening of any means of fixing components;
e) any impaired function of a component or part.
5 Test equipment
5.1 General
Unless otherwise specified, the tests may be applied by any suitable device because results are not dependent
upon the apparatus.
The equipment shall not inhibit deformation of the extension element, i.e. it shall be able to move so that it
can follow the deformation of the extension element during testing.
5.2 Masses
Masses shall be designed so that they do not reinforce the structure or re-distribute the stresses.
5.3 Glass/steel marbles
Marbles are made of solid glass with a 10 mm to 15 mm diameter. They shall be in a flexible bag large enough
to allow them to move in the bag during the test.
NOTE A bag that is approximately 50 % filled is considered loosel
...