ISO/FDIS 7173

Furniture — Chairs and stools — Determination of strength and durability

Ameublement — Chaises et tabourets — Détermination de la résistance et de la durabilité

General Information

• Status: Not Published
• ICS: 97.140 - Furniture
• Technical Committee: ISO/TC 136 - Furniture
• Drafting Committee: ISO/TC 136/WG 1 - Chairs - Methods of test
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 10-May-2023
• Completion Date: 10-May-2023

Relations

• Revises: ISO 7173:1989 - Furniture — Chairs and stools — Determination of strength and durability
• Effective Date: 03-Jun-2017

Standards Content (Sample)

DRAFT INTERNATIONAL STANDARD
ISO/DIS 7173
ISO/TC 136 Secretariat: UNI
Voting begins on: Voting terminates on:
2022-05-19 2022-08-11
Furniture — Chairs and stools — Determination of
strength and durability

Ameublement — Chaises et tabourets — Détermination de la résistance et de la durabilité

ICS: 97.140; 97.140
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
This document is circulated as received from the committee secretariat.
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
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WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 7173:2022(E)
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NOTIFICATION OF ANY RELEVANT PATENT
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PROVIDE SUPPORTING DOCUMENTATION. © ISO 2022
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ISO/DIS 7173:2022(E)
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ISO/DIS 7173:2022(E)
Contents Page

Foreword ....................................................................................................................................................................................................................................... vi

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 General test condition ....................................................................................................................................................................................3

4.1 Preliminary preparation ............................................................................................................................................................... 3

4.2 Application of forces .......................................................................................................................................................................... 3

4.3 Tolerances ................................................................................................................................................................................................... 3

5 Test equipment and apparatus .............................................................................................................................................................4

5.1 General ........................................................................................................................................................................................................... 4

5.2 Seat loading point template......................................................................................................................................................... 4

5.3 Floor ................................................................................................................................................................................................................. 7

5.4 Stops ................................................................................................................................................................................................................. 7

5.5 Seat loading pad..................................................................................................................................................................................... 7

5.6 Smaller seat loading pad ................................................................................................................................................................ 7

5.7 Back loading pad ................................................................................................................................................................................... 8

5.8 Local loading pad.................................................................................................................................................................................. 8

5.9 Foam for use with loading pads .............................................................................................................................................. 8

5.10 Seat impactor ........................................................................................................................................................................................... 8

5.10.1 Circular body ......................................................................................................................................................................... 8

5.10.2 Springs ......................................................................................................................................................................................... 9

5.10.3 Striking surface ................................................................................................................................................................... 9

5.11 Impact hammer ...................................................................................................................................................................................... 9

5.12 Armrest durability test apparatus .................................................................................................................................... 10

5.13 Test surface for castor testing ............................................................................................................................................... 11

5.14 Front load locator device ............................................................................................................................................................ 11

5.15 Loading discs ......... ................................................................................................................................................................................ 11

6 Test procedures – Seating other than work chairs ......................................................................................................11

6.1 General ........................................................................................................................................................................................................ 11

6.2 Determination of seat and back loading points ......................................................................................................12

6.2.1 General .....................................................................................................................................................................................12

6.2.2 Seating with a backrest .............................................................................................................................................12

6.2.3 Seating without a backrest .....................................................................................................................................12

6.3 Determination of angle of backrest inclination ......... ............................................................................................. 14

6.4 Seat static load and backrest static load test ........................................................................................................... 15

6.5 Seat front edge static load test .............................................................................................................................................. 17

6.6 Vertical load test on backrests .............................................................................................................................................. 17

6.7 Horizontal forward static load test on backrests................................................................................................. 17

6.8 Footrest static load test ............................................................................................................................................................... 18

6.9 Legrest static load test ................................................................................................................................................................. 19

6.10 Armrest sideways static load test ...................................................................................................................................... 19

6.11 Arm rest downwards static load test .............................................................................................................................. 19

6.12 Headrest static load test ............................................................................................................................................................. 20

6.13 Vertical upwards static load test on armrests ........................................................................................................ 20

6.13.1 Seating which can be moved when occupied ......................................................................................... 20

6.13.2 Stacking seating ............................................................................................................................................................... 21

6.14 Vertical static load test on auxiliary writing surfaces ..................................................................................... 21

6.15 Leg forward static load test ..................................................................................................................................................... 21

6.16 Leg sideways static load test ...................................................................................................................................................22

6.17 Combined seat and backrest durability test ............................................................................................................. 24

6.18 Seat front edge durability test ............................................................................................................................................... 27

6.19 Durability test on outdoor seating with a multi-position backrest ..................................................... 27

iii
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ISO/DIS 7173:2022(E)

6.20 Armrest durability test ................................................................................................................................................................28

6.21 Footrest durability test ................................................................................................................................................................28

6.22 Auxiliary writing surfaces durability test ..................................................................................................................28

6.23 Tipping seat operation test .......................................................................................................................................................28

6.24 Seat impact test ...................................................................................................................................................................................29

6.25 Backrest impact test ....................................................................................................................................................................... 29

6.26 Armrest impact test ........................................................................................................................................................................30

6.27 Drop tests ................................................................................................................................................................................................. 31

6.27.1 Drop test for stacking seating ............................................................................................................................. 32

6.27.2 Drop test from the height of a table ................................................................................................................ 33

6.28 Backward fall test ............................................................................................................................................................................. 33

6.29 Castor and chair base durability test ..............................................................................................................................34

6.29.1 Castor and chair base durability test for chairs with castors on all legs ......................34

6.29.2 Castor and chair base durability test for chairs with castor and glide

combinations ......................................................................................................................................................................34

6.30 Rolling resistance test of the unloaded chair ...........................................................................................................34

6.31 Seat side-to-side durability test in D-G points for single column seating .......................................34

6.31.1 Loading points ...................................................................................................................................................................34

7 Test procedures – Work Chairs .........................................................................................................................................................35

7.1 General ........................................................................................................................................................................................................ 35

7.2 Loading points ..................................................................................................................................................................................... 37

7.2.1 General ..................................................................................................................................................................................... 37

7.2.2 Loading point A ................................................................................................................................................................. 37

7.2.3 Loading point B ................................................................................................................................................................. 37

7.2.4 Loading point C ................................................................................................................................................................. 37

7.2.5 Loading point D ................................................................................................................................................................ 37

7.2.6 Loading point E ................................................................................................................................................................. 37

7.2.7 Loading point F ................................................................................................................................................................. 37

7.2.8 Loading point G ................................................................................................................................................................. 37

7.2.9 Loading point H ................................................................................................................................................................ 37

7.2.10 Loading point J .................................................................................................................................................................. 37

7.3 Combined seat and backrest static load test.............................................................................................................39

7.4 Seat front edge static load test ..............................................................................................................................................39

7.5 Armrest downward static load test – central ..........................................................................................................39

7.6 Armrest downward static load test – front ...............................................................................................................40

7.7 Armrest sideways static load test ......................................................................................................................................40

7.8 Footrest static load test ...............................................................................................................................................................40

7.9 Seat and backrest durability test ........................................................................................................................................ 41

7.10 Armrest durability test ................................................................................................................................................................ 42

7.11 Swivel test ................................................................................................................................................................................................ 42

7.12 Footrest durability test ................................................................................................................................................................ 42

7.13 Castor and chair base durability test .............................................................................................................................. 42

7.14 Rolling resistance test of the unloaded chair ........................................................................................................... 42

8 Test procedures – Loungers ..................................................................................................................................................................42

8.1 General ........................................................................................................................................................................................................ 42

8.2 Seat and backrest static load test ....................................................................................................................................... 43

8.3 Additional seat and legrest static load test ................................................................................................................ 43

8.4 Seat and backrest durability test ........................................................................................................................................44

8.4.1 Seat and backrest durability test procedure ..........................................................................................44

8.4.2 Additional seat durability test procedure ................................................................................................44

8.5 Durability test on backrest mechanism ........................................................................................................................ 45

8.6 Armrest downwards static load test ............................................................................................................................... 45

8.7 Armrest durability test ................................................................................................................................................................ 45

8.8 Impact test ............................................................................................................................................................................................... 45

8.9 Lifting test for mobile loungers ............................................................................................................................................ 47

Annex A (normative) Seat loading pad data ........................................................................................................................................... ...48

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ISO/DIS 7173:2022(E)

Annex B (informative) Armrest loading pad details .......................................................................................................................51

Annex C (normative) Front load locator device (5.14) ...................................................................................................................52

Annex D (informative) Purpose and applicability of test methods .................................................................................58

Annex E (informative) Suggested loads and cycles ...........................................................................................................................64

Bibliography .............................................................................................................................................................................................................................70

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ISO/DIS 7173:2022(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 of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 136, Funiture.

This second edition cancels and replaces the first edition (ISO 7173:1989), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— Scope has been revised;
— Further terms and definitions were added;

— Further test methods for work chairs and seating other than work chairs were added;

— New Annexes were added.

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.
© ISO 2022 – All rights reserved
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DRAFT INTERNATIONAL STANDARD ISO/DIS 7173:2022(E)
Furniture — Chairs and stools — Determination of
strength and durability
1 Scope

This International Standard specifies test methods for the determination of strength and durability

of the structure of all types of seating without regard to use, materials, design/construction or

manufacturing process.

This International Standard does not apply to children’s highchairs, table mounted chairs and bath

seats.

Test methods for the assessment of ageing, degradation, ergonomics and electrical functions are not

included.

The test methods are not intended to assess the durability of upholstery materials, such as upholstery

filling materials and upholstery covers.

This International Standard does not include any requirements. Requirements for different end uses

can be found in other Standards.
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 48-4:2018, Rubber, vulcanized or thermoplastic — Determination of hardness — Part 4: Indentation

hardness by durometer method (Shore hardness)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological 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
structure

load bearing parts of furniture such as the frame, seat, backrest and arm supports and suspension

3.2
legrest
extension of the seat area intended to support the legs of the user

Note 1 to entry: A legrest can or cannot be permanently attached to the structure of the item of seating, and may

not be suitable for use as an item of seating itself.
3.3
footrest

extension of the seat area, whether attached or not to the structure of the item of seating, intended to

support the feet of the user
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ISO/DIS 7173:2022(E)
3.4
work chair

swivelling chair, with or without arm rests, for use by one adult in the office (for example working with

a computer), whose upper part, which includes the seat and backrest, is supported on a single column

and can rotate in the horizontal plane and is at least adjustable in height
3.5
backrest

element that supports the back of the user higher than 200 mm above the seat loading point

3.6
armrest

part of the seating able to support the arms of the user when seated, 100 mm or higher above the height

of the seat loading point
3.7
armrest length

horizontal distance along the armrest within an envelope down from the top of the armrest that is

20 mm deep
Note 1 to entry: See Figure 1.
Key
1 armrest
l armrest length
Figure 1 — Armrest length

[SOURCE: ISO 24496:2021, 3.3; modified – "horizontal" added and Note 1 to entry adapted to correct

Figure number.]
3.8
multiple seating unit
unit with a seating surface wider/longer than 1 100 mm
3.9
lounger

item of seating intended for reclined posture with at least one backrest position such that backrest

angle is 45 degrees or less to the horizontal, and a leg rest which is an integral part of the product and

intended to support the full body weight of a user
Note 1 to entry: See Figure 37.
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ISO/DIS 7173:2022(E)
3.10
single column seating

item of seating, whose upper part, which includes the seat, is mounted on a single support with a

diameter of up to 120 mm at its narrowest point
4 General test condition
4.1 Preliminary preparation

The furniture shall be tested as delivered. Knock-down furniture shall be assembled according to the

instructions supplied with it. If the instructions allow the furniture to be assembled or combined in

different ways, the most adverse combination shall be used for each test. Knock-down fittings shall be

tightened before testing. Further tightening shall not take place.

For seating that is designed to be fixed to the structure of a building, the unit shall be mo

...