ANSI/BIFMA X5.

11-2015

General-Purpose Large Occupant Office Chairs –

Tests

American National Standard for Office Furnishings

 ANSI/BIFMA X5.11-2015

American National Standard

for Office Furniture

General-Purpose Large Occupant Office

Chairs - Tests

Sponsor

BIFMA
678 Front Avenue NW, Suite 150
Grand Rapids, MI 49504-5368
Phone: (616) 285-3963
Fax: (616) 285-3765
www.bifma.org

Approved January 5, 2015

American National Standards Institute

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 ANSI/BIFMA X5.11-2015

American National Standard

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Printed in the United States of America

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 ANSI/BIFMA X5.11-2015

Foreword

This standard defines specific tests, laboratory equipment, conditions of test, and recommended
minimum levels to be used in the test and evaluation of the safety, durability, and structural
adequacy of general-purpose large occupant office chairs.

The material presented in this standard was developed as a result of the efforts of the members
of BIFMA and reviewed by a broad representation of interested parties, government
organizations and commercial testing and procurement and interior design organizations. In the
fall of 2011, BIFMA partnered with Mississippi State University to conduct testing with large
occupants for seating analysis. The study was conducted on 20 subjects (10 male and 10
female) with weights ranging from 135 to 187 kg (298 to 413 lbs.). The study was completed in
the spring of 2013 and the report, “Measuring Humans for Heavy Duty Chair Testing and
Design” authored by J. Zhang, B. Tackett, and B. Martin was used to assist BIFMA in
determining test levels for this standard. The requirements given in this standard are expected
to be representative of the 99th percentile or greater use (load application) by 400 lb. persons.

The original work on a seating standard was completed in May 1974 by the BIFMA Engineering
Committee on Chair Standards for General-Purpose Office Chairs with subsequent revisions in
1985, 1993, 2002, and 2011. The original work on this General-Purpose Large Occupant Chair
standard was completed in 2014 by the BIFMA Engineering Committee and, particularly by its
Subcommittee on Chair Standards. During the periods from 2011 to 2014 the Subcommittee on
Chair Standards conducted reviews of the draft standard to ensure that the tests accurately
describe the proper means of evaluating the safety, durability, and structural adequacy of
general-purpose large occupant office chairs. The drafts were submitted to the membership of
BIFMA for approval in 2013 and 2014.

A canvass of interested parties and stakeholders was conducted in accordance with the
requirements of an ANSI accredited standards developer. After completion of the canvass
process, the standard was subsequently submitted to the American National Standards Institute
for approval as an American National Standard. Approval by ANSI was given on January 5,
2015.

Suggestions for the improvement of this standard are welcome. The suggestions should be
sent to BIFMA, 678 Front Ave. NW, Suite 150, Grand Rapids, MI 49504-5368.

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 ANSI/BIFMA X5.11-2015

Contents

Section ............................................................................................................ Page

1 Scope ........................................................................................................ 7
2 Definitions.................................................................................................. 8
3 General ................................................................................................... 10
3.1 Testing Considerations ................................................................ 10
3.2 Manufacturer’s Instructions ......................................................... 11
3.3 Figures......................................................................................... 11
3.4 Figure Symbols............................................................................ 11
3.5 Measurements ............................................................................. 12
3.6 Tolerances ................................................................................... 12
3.7 Test Force Application ................................................................. 12
3.8 Pretest Inspection ........................................................................ 12
3.9 Recommended Test Report Format ............................................ 13
3.10 Temperature and Humidity Considerations ................................. 13
4 Types of Chairs ....................................................................................... 15
5 Seat Width Measurement ........................................................................ 18
6 Backrest Strength Test - Static - Type I .................................................. 22
7 Backrest Strength Test - Static - Type II and III ...................................... 27
8 Drop Test - Dynamic ............................................................................... 30
9 Swivel Test - Cyclic ................................................................................. 33
10 Tilt Mechanism Test - Cyclic ................................................................... 35
11 Seating Durability Tests - Cyclic.............................................................. 37
12 Stability Tests .......................................................................................... 40
13 Arm Strength Test - Vertical - Static ........................................................ 50
14 Arm Strength Test - Horizontal - Static.................................................... 53
15 Backrest Durability Test - Cyclic - Type I ................................................ 57
16 Backrest Durability Test - Cyclic - Type II and Type III ........................... 64
17 Caster/Chair Base Durability Test - Cyclic .............................................. 69
18 Leg Strength Test - Front and Side Application ...................................... 75
19 Arm Durability Test - Cyclic ..................................................................... 78
20 Out Stop Tests for Chairs with Manually Adjustable Seat Depth ............ 80
21 Tablet Arm Static Load Test. ................................................................... 82
22 Tablet Arm Load Ease Test - Cyclic ........................................................ 84
23 Structural Durability Test ......................................................................... 86

Appendix A: Impact Test Bag Construction Details ............................................ 87

Appendix B: Stability Disk Construction Details .................................................. 94

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 ANSI/BIFMA X5.11-2015

Table

1 Test Guide by Chair Type ....................................................................... 16

Figures

4 Types of Chairs ....................................................................................... 14

5 Seat Width Measurement ................................................................... 17-18

6 Backrest Strength Test - Static -Type I .............................................. 19-21

7 Backrest Strength Test - Static - Type II and III ................................. 24-26

8 Drop Test - Dynamic ............................................................................... 29

9 Swivel Test - Cyclic ................................................................................. 32

10 Tilt Mechanism Test - Cyclic ................................................................... 34

11 Seating Impact Tests - Cyclic and Front Corner Load-Ease ........... 36 & 38

12 Stability Tests ......................................................................... 40, 42, 44-47

13 Arm Strength Test - Vertical - Static ................................................... 49-50

14 Arm Strength Test - Horizontal - Static.................................................... 52

15 Backrest Durability Test - Cyclic - Type I ................................... 54-56 & 59

16 Backrest Durability Test - Cyclic - Type II and Type III .............. 61-63 & 66

17 Caster/Chair Base Durability Test - Cyclic ...................................... 68 & 70

18 Leg Strength Test - Front and Side Application .............................. 73 & 74

19 Arm Durability Test - Cyclic ..................................................................... 77

20 Out Stop for Chairs with Manually Adjustable Seat Depth ...................... 79

21 Tablet Arm Static Load Test .................................................................... 81

22 Tablet Arm Load Ease Test - Cyclic ........................................................ 83

23 Structural Durability Test ......................................................................... 85

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 ANSI/BIFMA X5.11-2015

American National Standard

for Office Furnishings

General-Purpose Large Occupant Office Chairs – Tests

1 Scope

This standard is intended to provide manufacturers, specifiers, and users with a common basis
for evaluating the safety, durability, and structural adequacy of office chairs for large occupants
(often referred to as “users” throughout this standard).

Large occupant office chairs are normally used in an office environment and may include, but
are not limited to those seating styles typically referred to as: executive/management,
task/secretarial, side/guest chairs, and stacking chairs. This standard describes the means of
evaluating large occupant office chairs, independent of construction materials, manufacturing
processes, mechanical designs or aesthetic designs. This standard does not address lounge
seating, stools, flammability, surface material durability, cushioning materials, or product
emissions.

The standard defines specific tests, the laboratory equipment that may be used, the conditions
of tests, and the minimum acceptance levels to be used in evaluating large occupant office
chairs. The acceptance levels and test parameters given in this standard are based on the
actual field use and test experience of BIFMA members. Where appropriate, the National
Health and Nutrition Examination Survey (NHANES) 05-08, which indicates the 99.5th percentile
male weight approaches 400 pounds, was used in the development of the tests. Chairs that are
designed to this standard must have seat widths of 560 mm (22 in.) or greater (See Section 5).
Chairs with seat widths at or wider than this may be used by smaller individuals, but may not be
ergonomically correct or comfortable for smaller users. Users of this standard are discouraged
from applying this standard to general office chairs, which are covered by the X5.1 standard.

The tests were developed with an estimated product life of ten years based on single-shift
usage. Product life will be affected by user size/weight, product use, care and maintenance,
environment, and other factors, and, as such, product compliance to this standard does not
necessarily guarantee a ten-year product life.

The tests in this standard are intended to assess the performance of new products only. They
are not intended to assess a product that has been in use.

ISO 17025 requirements for measurement uncertainty do not apply to this standard.

Note: General-purpose office chairs are covered by ANSI/BIFMA X5.1-2011; and Lounge and
Public Seating products are covered by ANSI/BIFMA X5.4-2012. Where appropriate, the
Civilian American and European Surface Anthropometry Resource (CAESAR) anthropometric
database (2002 report), which indicates the 95th percentile male weighs 253 pounds, was used
in the development of the X5.1 and X5.4 tests.

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 ANSI/BIFMA X5.11-2015

2 Definitions
Note: Refer to BIFMA PD-1 Industry Product Definitions for related terms not included in this
standard. Otherwise, the common dictionary definition shall be used for terms not
defined in this section or in BIFMA PD-1. In case of a conflict between the definitions in
this standard and PD-1, the definitions in this standard shall apply.
2.1 acceptance level: The performance level required to pass the test.
2.2 appropriate rate: Any rate that avoids resonant frequencies, excessive heating, shock
loads, etc.
2.3 back stop position: The position of the unit when the unit's tilt mechanism first contacts
its rearward mechanical stop, regardless of the force on the backrest.
2.4 CMD: Chair Measuring Device used for the measurement of seating products.

2.5 CMD-1 Chair Measurement Procedure: A universal procedure for the BIFMA Chair
Measuring Device. (ISO/TR 24496 Procedure may be used for the ISO CMD).
2.6 cycle: A complete operation of loading and unloading or of stress reversal; one complete
revolution in a cyclic manner.
2.7 counterbalancing force: A force or influence that offsets an opposing force.
2.8 force: A vector quantity, expressed in newton (N) or pounds force (lbf.) that tends to
produce an acceleration of a body in the direction of its application.
2.9 form-fitting device: A device that distributes a force over a 305 ± 13 mm x 70 ± 32 mm
(12 ± 0.5 in. x 2.75 ± 1.25 in.) area of a backrest. The device will be shaped to
approximate the contours of the chair backrest.
2.10 front stop position: The position of the unit when the unit's tilt mechanism first contacts
its forward mechanical stop.
2.11 functional load: The level of loading or force considered typical of hard use.
2.12 general-purpose office chairs: Chairs normally used in an office environment. These
may include, but are not limited to those seating styles typically referred to as:
executive/management, task/secretarial, side/guest chairs, stacking chairs, tablet arm
chairs and stools.
2.13 general-purpose large occupant office chairs: Chairs normally used in an office
environment for larger persons. To qualify as such the chair shall have a minimum seat
pan width of 560 mm (22 inches). These may include, but are not limited to those seating
styles typically referred to as: executive/management, task/secretarial, side/guest chairs,
stacking chairs, and tablet arm chairs.
2.14 IFD: Indentation Force Deflection. See Test B1, Indentation Force Deflection Test, in
Methods of testing flexible cellular materials - Slab, bonded, and molded urethane foams,
ASTM D 3574.

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 ANSI/BIFMA X5.11-2015

2.15 lbf.: Abbreviation for pounds-force. The corresponding unit in the SI (Systeme
International) system is the newton (N).
2.16 load: The weight to which a structure is subjected; a weight or force applied to a product;
force acting on a surface, usually caused by the action of gravity.
2.17 load-bearing structure/surface: Any element that supports loads during use. Foam and
fabric, for example, are not generally considered load-bearing surfaces, nor are some
portions of waterfall edges.
2.18 loss of serviceability: The failure of the product to support its intended load or to perform
all of its normal functions or adjustments.
2.19 lounge seating: Seating that is intended for use in indoor public spaces such as waiting,
reception, or lounge areas. Lounge seating includes products with single seat units or
units with multiple seating positions within one unit. Lounge seating may be fixed to the
building structure or freestanding. It is generally not adjustable for personal use.
2.20 manufacturer's instructions: Instructions for assembly, operation, and/or maintenance
supplied by the manufacturer to the customer.
2.21 N (newton): a unit of force in the SI (Systeme International) System, also known as the
Metric System.
2.22 normal use condition: For consistency, the midpoint of any adjustment range, such as
the height adjustment or counter balancing force adjustment unless otherwise specified in
the test method.
2.23 pedestal base: A base that supports a chair by a single central structural member such as
a column.
2.24 pivoting backrest: A backrest that rotates on a horizontal axis above the height of the
seat.
2.25 proof load: The level of loading or force in excess of hard use.
2.26 stool: A chair with a seat height greater than 610 mm (24 in.), intended to allow the user
to sit at standing-height work surfaces such that the user’s feet are not supported by the
floor.
2.27 tablet arm: A surface attached to a chair that has the primary function to support tasks
such as writing and short-term reference material handling. These surfaces typically do
not have independent support legs and are not intended to support a person’s weight.
The support for the writing surface is dependent on the support for the seat. These
surfaces may be fixed or have tilt and/or stowaway capability.
2.28 test surface: The horizontal hard surface, (concrete or other non-deforming surface) on
which the chair to be tested is placed during testing.
2.29 worst-case condition: The product and/or condition (i.e. size and construction of a given
unit type) most likely to be adversely affected by an individual test or testing sequence.

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 ANSI/BIFMA X5.11-2015

3 General

3.1 Testing Considerations

3.1.1 The testing and evaluation of a product according to this standard may require the use of
materials and/or equipment that could be hazardous. This document does not purport to
address all the safety aspects associated with the use of those materials and/or equipment.
Anyone using this standard has the responsibility to consult the appropriate authorities and to
establish health/safety practices and any applicable regulatory requirements prior to the use of
the materials or equipment described.
3.1.2 The types of tests to be employed fall into the following general categories:
a) Static load applications;
b) Dynamic load applications;
c) Durability and/or life cycle testing.
3.1.3 The tests described in this standard, other than the specifically identified component
tests are intended to evaluate the entire chair assembly, including the base, tilt mechanism,
height adjustment device, locking/adjustment mechanisms, seat/backrest attachment, etc.
3.1.4 Two types of load levels are used:
a) Functional loads are generally used to evaluate the durability/longevity of the products
under hard use and typically define acceptable performance in terms of continuing
serviceability.
b) Proof loads are generally used to evaluate the performance of the product in excess of
hard use and typically define acceptable performance in terms of structural integrity.
3.1.5 Each manufacturer’s model or unit type in any configuration (allowed by the
manufacturers planning guide) shall comply with applicable requirements when tested in
accordance with this voluntary standard. Only worst-case product, condition, and/or furniture
configurations (including height adjustment capability) need to be tested. A worst-case
product/condition/configuration shall be representative of all models or units of the type tested.
If “worst-case condition” is not readily evident, a case-by-case product line analysis by the
manufacturer in consultation with the designated testing facility may be necessary, taking into
consideration any special attributes, methods of construction, materials, and/or design features,
etc. Instruction documents and other literature provided by the manufacturer will be helpful in
determining which products and/or product configurations that are implicitly or explicitly
recommended by the manufacturer when determining compliance; it is expected that any and all
configurations recommended by the manufacturer will be able to meet the acceptance levels of
the tests in this standard. Note: More than one product may have to be tested for different tests
to cover a product from a worst-case condition standpoint.
3.1.6 The test methods included in this standard require the use of fixtures and/or load
adapters to perform the tests. Some products and/or constructions may need special test
fixtures, load adapters, etc., to perform these tests in a manner that meets the intent of the
standard. This is especially true of products with complex articulation of joints, unique motions
or adjustments, or non-traditional use of materials. The users of this standard are encouraged
to develop appropriate fixtures and/or test variations that more accurately simulate application of
loads, etc., for given unique products in a manner that reflects actual use. Fixtures, load
adapters, etc., shall not add structure or provide support to the product being tested. If a test

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 ANSI/BIFMA X5.11-2015

procedure cannot be performed as specified in the procedures due to the design of the product,
it shall be carried out as far as possible as described, and deviations from the procedure shall
be recorded in the test report (See Section 3.9). Independent/consumer testing facilities may
need to consult with product manufacturers to ensure any special conditions are considered
during testing.
3.1.7 It is not intended that all of the tests in this standard be conducted on a single unit. The
tests may be performed on a series of units at the discretion of the manufacturer. When a test
requires a functional load and a proof load be applied as part of the test criteria, the functional
and proof loads shall be applied to the same component or unit. The tests may be performed in
any sequence unless otherwise specified within a given test section; the functional load shall
always precede the proof load.
3.1.8 Table 1 indicates the tests that when applicable shall be performed on each type of
chair, as defined in Section 4.

3.2 Manufacturer's Instructions

When supplied, manufacturer’s assembly instructions shall be followed during the initial
assembly or setup of the chair. When a manufacturer recommends specific instructions or
maintenance adjustments that may be required in order to keep the product in good operating
condition, unless otherwise specified by these test procedures, the manufacturer’s assembly,
operating and maintenance instructions shall be followed.

3.3 Figures
Figures provided in this standard are intended as guidelines only and may not be representative
of all possible test configurations.

3.4 Figure Symbols

= FORCE

= EVENLY DISTRIBUTED FORCE

= TEST WEIGHT

= SECURED OR CLAMPED TO TEST

PLATFORM

= HORIZONTAL MOTION PREVENTED

= DIRECTION OR MOTION

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 ANSI/BIFMA X5.11-2015

3.5 Measurements
The BIFMA Chair Measurement Device (CMD) or the ISO CMD shall be used in determining
applicable setup measurements. The setup measurement may be determined for an individual
model and used for all tests for that model. In order for measurements to be "universally"
acceptable, only Chair Measuring Devices (CMD) built to BIFMA or ISO specifications may be
used. Requests for more information regarding the BIFMA or the ISO CMD may be directed to
BIFMA.

3.6 Tolerances
Unless otherwise specified, tolerances shall be:

• Test Weights, Forces, Velocities, and Time, ± 5%

• Linear measurements, ± 1.5 mm (1/16 in.)
• Angles, ± 5 degrees
• Level, within 5 mm per meter (0.06 in. per linear foot) or ± 0.3 degrees
• Cycle requirements are minimums.

Test weights, forces, dimensions, angles, times, rates and velocities used to perform the test
shall be targeted at the nominal values specified and shall be subject to the above tolerances.
Devices used to calibrate test devices and/or machines shall be calibrated to one-fourth of the
above tolerance, with the exception of Level, which shall be calibrated to one-half.

3.7 Test Force Application

To ensure that negligible dynamic force is applied, the forces in the static force tests shall be
applied sufficiently slowly until the target load/force is achieved. Where time limits are given,
loads and forces shall be maintained according to the tolerance given in Section 3.6 unless
otherwise specified.

3.8 Pretest Inspection

Before beginning the testing, visually inspect the unit thoroughly. Record any defects so that
they are not assumed to have been caused by the tests.

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 ANSI/BIFMA X5.11-2015

3.9 Recommended Test Report Format

When a test report is required, the following information should be included:

1. A title: (i.e., "Test Report");
2. Name and address of the laboratory, and the location where the tests were carried out, if
different from the address of the laboratory;
3. Unique identification of the report (such as serial number) and on each page an
identification in order to insure that the page is recognized as part of the test report and a
clear identification of the end of the test report;
4. Name and address of the client (where applicable);
5. Description and unambiguous identification of the item tested (i.e., model number,
manufacturing date, etc.);
6. Characterization and condition of the test item;
7. Date of receipt of the test item;
8. Date(s) of the performance of test;
9. Identification of the test method used;
10. Any additions to, deviations from, or exclusions from the test method (such as
environmental conditions);
11. The name(s), function(s) and signature(s), or equivalent identification of the person(s)
authorizing the test report;
12. Where relevant, a statement to the effect that the results relate only to the items tested;
13. Date of issue of the report;
14. Test results with, where appropriate, the units of measurement and a statement of
compliance/non-compliance with requirements and/or specifications;
15. A statement that the report shall not be reproduced, except in full, without the written
approval of the laboratory.

3.10 Temperature and Humidity Considerations

Products should be conditioned to ambient laboratory conditions for temperature and relative
humidity prior to testing.

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 ANSI/BIFMA X5.11-2015

Figure 4a - Type I - Tilting Chair

Figure 4b - Type II - Fixed Seat Angle, Tilting Backrest

Figure 4c - Type lll - Fixed Seat Angle, Fixed Backrest

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 ANSI/BIFMA X5.11-2015

4 Types of Chairs

To accommodate a wide variation in chair designs, it may be necessary to apply the tests to
various types of chairs.

If a product can be classified as more than one chair type, it shall be tested under all applicable
classifications. For example, a chair with a locking tilt mechanism would be classified as both a
Type l (when the mechanism is unlocked) and Type lll chair (when the mechanism is locked).
Chair types are used to determine specific tests parameters and test applicability. Chairs that
do not fit into one of these three types will exist (eg., backless chairs) and may still be tested to
the applicable tests/requirements within this standard.

The following classification of types and features of chairs provides standard product
identification:

4.1 Chair Type: Type I. Tilting chair:

A chair with a seat and backrest that tilt (either in unison or in
synchronization) with a counterbalancing force. Chairs of this type are
typically referred to as synchro-tilt, center-tilt, knee-tilt, etc.
(See Figure 4a)

Type II. Fixed seat angle, tilting backrest:

A chair that provides a fixed seat angle with a tilting backrest.
(See Figure 4b)

Type lll. Fixed seat angle, fixed backrest:

A chair that provides a fixed seat angle with a fixed backrest.
This may include chairs with legs, including sled base chairs.
(See Figure 4c)

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 ANSI/BIFMA X5.11-2015

TABLE 1 – Test Guide by Chair Type

Section
Number Description Type I Type II Type III
5 Seat Width Measurement X X X
6 Backrest Strength Test - Static - Type l X
7 Backrest Strength Test - Static - Type II X X
and III
8 Drop Test – Dynamic X X X
9 Swivel Test – Cyclic X X X
10 Tilt Mechanism Test - Cyclic X X
11 Seating Durability Test - Cyclic X X X
12 Stability Tests X X X
13 Arm Strength Test - Vertical - Static X X X
14 Arm Strength Test - Horizontal - Static X X X
15 Backrest Durability Test - Cyclic - Type I X
16 Backrest Durability Test - Cyclic - Type II X X
and Type III
17 Caster/Chair Base Durability Test - Cyclic X X X
18 Leg Strength Test - Front and Side X X X
Application
19 Arm Durability Test - Cyclic X X X
20 Out Stop Tests for Chairs with Manually X X X
Adjustable Seat Depth
21 Tablet Arm Static Load Test X X X
22 Tablet Arm Load Ease Test - Cyclic X X X
23 Structural Durability Test X

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 ANSI/BIFMA X5.11-2015

Front of Chair Rear of Chair

As measured from the

back -- 175 mm ±15 mm Top View of Chair
(6.9 in. ± 0.6 in.)
Zone for determining
Seat Width

175 mm mark
on template –
(See Fig. 5b)

Side View of Chair

Figure 5a – Seat Width Measurement

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 ANSI/BIFMA X5.11-2015

The template shall be a rigid material.

The thickness shall not exceed 25 mm
(1 in.). The vertical section shall be 577
mm (22.7 in.) high and the horizontal
section shall be 605 mm (23.8 in.) long.

Seat Width
Measurement
300 mm Reference mark
(11.8 in.)

95°

175 mm
(6.9 in.)

Figure 5b - Rearward Seat and Back Template

5 Seat Width Measurement

5.1 Applicability
This test applies to all chair types.

5.2 Purpose of Test

The purpose of this test is to evaluate the width of the seat.

5.3 Test Setup

The chair shall be placed in an upright position.

5.4 Test Procedure

Determine seat width using the template as shown in Figure 5. Alternately, determine the seat
width according to the CMD (see 3.5).

5.4.1 Position the Rearward Seat and Back Template (See Figure 5b) into the chair until it just
touches the seat and back.

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 ANSI/BIFMA X5.11-2015

5.4.2 Mark the seat at the 175 mm (6.9 in.) location per the template and draw a zone across
the width of the seat that is +/- 15 mm (0.6 in.) fore and aft of the 175 mm mark (See
Figure 5a).
5.4.3 Measure the narrowest seat width within the 30 mm (1.2 in.) seat width zone.

5.5 Acceptance Level

The seat width shall be 560 mm (22 in) minimum.

Height above seat

using scale on CMD

Figure 6a - Height Determination

Backrest Strength Test - Static - Type l

Form-fitting
device

406 mm (16.0 in.)

Figure 6b - Positioning of Form-Fitting Device for Backrests Higher than 452 mm

(17.8 in.) Backrest Strength Test - Static - Type I

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 ANSI/BIFMA X5.11-2015

Form-fitting device

Less than 452 mm (17.8 in.)

height above seat
Device even with top of
load bearing structure

Figure 6c - Positioning of Form-Fitting Device for Backrests Lower than 452 mm

(17.8 in.) Backrest Strength Test - Static - Type l

> 20°

Pivot point of
pivoting – type
backrest pad

90°± 10°

Direction of force
application (backrest
in its most backrest
position)

Figure 6d - Force Application for Backrests that Pivot Greater than 20°
Backrest Strength Test - Static - Type l

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 ANSI/BIFMA X5.11-2015

Position per 6.3

90°± 10°
Direction of force
application (backrest
in its most rearward
position)

Figure 6e - Force Application for All Other Backrests

Backrest Strength Test - Static - Type l

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 ANSI/BIFMA X5.11-2015

6 Backrest Strength Test - Static - Type l (See Figures 6a through 6e)

6.1 Applicability
This backrest strength test shall be performed on Type I chairs. For chairs with tilt locks, locking
the chair changes the chair type (See Section 4) and must also be tested according to Section 7
in the upright locked position. An additional chair may be used for the Section 7 testing.
Note: This test does not apply to chairs with backrest height less than 200 mm (7.9 in.).

6.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chair to withstand stresses such as those
caused by the user exerting a rearward force on the backrest of the chair.

6.3 Test Setup

6.3.1 The chair shall be placed on a test surface in an upright position and the base shall be
restrained from movement, but shall not restrict movement of the backrest or arms of the
chair. Figure 6e shows one acceptable method of restraining the chair.
6.3.2 If adjustable features are available, all adjustments shall be set at normal use conditions,
except for height-adjustable pivoting backrests which shall have the pivot point set at its
maximum height or 406 mm (16.0 in.) whichever is less.
6.3.3 After making the above adjustments, determine points 406 mm (16 in.) and 452 mm
(17.8 in.) above the seat. (See Figure 6a and Section 3.5). Mark these points on the
vertical centerline of the backrest.
a) If the top of the load-bearing structure/surface of the backrest is greater than or equal
to 452 mm (17.8 in.) above the seat, position the center of the form-fitting device
(See Definition 2.9) 406 mm (16 in.) above the seat. (See Figure 6b).
b) If the top of the load-bearing structure/surface of the backrest is less than 452 mm
(17.8 in.) above the seat, position the top of the form-fitting device even with the top
of the load-bearing structure/surface. (See Figure 6c).
c) If the unit has a pivoting backrest that stops at a position less than or equal to 20
degrees rearward (with the support structure in its most upright position - see Figure
6d), position the form-fitting device as directed in a) or b). If the unit has a pivoting
backrest that stops at a position greater than 20 degrees rearward of the backrest,
position the center of the form-fitting device at the height of the pivoting point. (See
Figure 6d).

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 ANSI/BIFMA X5.11-2015

6.3.4 Attach a loading device (front push or back pull) to the horizontal center of the backrest
as determined above. With the backrest at its back stop position, apply a force that is
initially 90 degrees ± 10 degrees to the plane of the backrest. (See Figure 6e). The force
is not intended to be maintained at 90 degrees ± 10 degrees throughout the loading of
the backrest. If applying the load with a cable and pulley system, the cable must initially
be a minimum of 762 mm (30 in.) in length from the attachment point to the pulley. The
angle of the backrest plane may be determined by the angle of the plane of the front of
the CMD upright.
Note: Where the design of the chair does not allow the transfer of force(s) from the form-fitting
device to the load-bearing structure/surface, then a bridging device 38 mm to 102 mm
(1.5 in. to 4 in.) in height may be used to span the width of the load-bearing
structure/surface.

6.4 Test Procedures

6.4.1 Functional Load

a) A force of 890 N (200 lbf.) shall be applied to the backrest at the backstop position
for one (1) minute. If the backrest/tilt lock mechanism will not accept the load due to
gradual slipping of the adjustment mechanism during the load application, set the
backrest to its most rearward (stopped) position, then apply the specified load(s).
b) Remove the load.
6.4.2 Proof Load
a) A force of 1,334 N (300 lbf.) shall be applied to the backrest at the backstop position
for one (1) minute. If the backrest/tilt lock mechanism will not accept the load due to
gradual slipping of the adjustment mechanism during the load application, set the
backrest to its most rearward (stopped) position, then apply the specified load(s).
b) Remove the load.

6.5 Acceptance Level

6.5.1 Functional Load
There shall be no loss of serviceability to the chair.
6.5.2 Proof Load
There shall be no sudden and major change in the structural integrity of the chair. Loss of
serviceability is acceptable.

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 ANSI/BIFMA X5.11-2015

Height above seat

using scale on CMD

Figure 7a - Height Determination

Backrest Strength Test - Static - Type ll and lll

Form-fitting device

406 mm (16.0 in.)

Figure 7b - Positioning of Form-Fitting Device for Backrests Higher than 452 mm

(17.8 in.) Backrest Strength Test - Static - Type ll and lll

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 ANSI/BIFMA X5.11-2015

Form-fitting device

Less than 452 mm (17.8 in.)

height above seat

Device even with top of

load bearing structure

Figure 7c - Positioning of Form-Fitting Device for Backrests Lower than 452 mm

(17.8 in.) Backrest Strength Test - Type Il and lll

> 20°

Pivot point of
pivoting – type
backrest pad

90°± 10°

Direction of force
application (backrest
in its most backrest
position)

Figure 7d - Force Application for Backrests that Pivot Greater than 20°
Backrest Strength Test - Static - Type ll and lll

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 ANSI/BIFMA X5.11-2015

Position per 7.3

90°± 10°

Position per 7.3

90°± 10°

Figure 7e Force Application for All Other Backrests

Backrest Strength Test - Static - Types ll and lll

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 ANSI/BIFMA X5.11-2015

7 Backrest Strength Test - Static - Type II & lll (See Figures 7a through 7e)

7.1 Applicability
This backrest strength test shall be performed on Type Il and lll chairs.
Note: This test does not apply to chairs with backrest height less than 200 mm (7.9 in.).

7.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chair to withstand stresses such as those
caused by the user exerting a rearward force on the backrest of the chair.

7.3 Test Setup

7.3.1 The chair shall be placed on a test surface in an upright position and the base shall be
restrained from movement, but shall not restrict movement of the backrest or arms of the
chair. Figure 7e shows one acceptable method of restraining the chair.
7.3.2 If adjustable features are available, all adjustments shall be set at normal use conditions,
except for height-adjustable pivoting backrests which shall have the pivot point set at its
maximum height or 406 mm (16.0 in.) whichever is less.
7.3.3 After making the above adjustments, determine points 406 mm (16 in.) and 452 mm
(17.8 in.) above the seat. (See Figure 7a and Section 3.5). Mark these points on the
vertical centerline of the backrest.
a) If the top of the load-bearing structure/surface of the backrest is greater than or equal
to 452 mm (17.8 in.) above the seat, position the center of the form-fitting device
(See Definition 2.9) 406 mm (16 in.) above the seat. (See Figure 7b).
b) If the top of the load-bearing structure/surface of the backrest is less than 452 mm
(17.8 in.) above the seat, position the top of the form-fitting device even with the top
of the load-bearing structure/surface. (See Figure 7c).
c) If the unit has a pivoting backrest pad (See figure 7d) that stops at a position less
than or equal to 20 degrees rearward of vertical (with the support structure in its most
upright position), position the form-fitting device as directed in a) or b). If the unit has
a pivoting backrest that stops at a position greater than 20 degrees rearward of
vertical (with the support structure in its most upright position), position the center of
the form-fitting device at the height of the pivoting point. (See Figure 7d).

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 ANSI/BIFMA X5.11-2015

7.3.4 Attach a loading device (front push or back pull) to the horizontal center of the backrest
as determined above. With the backrest at its back stop position, apply a force that is
initially 90 degrees ± 10 degrees to the plane of the backrest (see Figure 6e). The force
is not intended to be maintained at 90 ± 10 degrees throughout the loading of the
backrest. If applying the load with a cable and pulley system, the cable must initially be
a minimum of 762 mm (30 in.) in length from the attachment point to the pulley. The
angle of the backrest plane may be determined by the angle of the plane of the front of
the CMD upright.
Note: Where the design of the chair does not allow the transfer of force(s) from the form-fitting
device to the load-bearing structure/surface, then a bridging device 38 mm to 102 mm
(1.5 in. to 4 in.) in height may be used to span the width of the load-bearing
structure/surface.
7.4 Test Procedures
7.4.1 Functional Load
a) A force of 667 N (150 lbf.) shall be applied to the backrest at the backstop position
for one (1) minute. If the backrest/tilt lock mechanism will not accept the load due to
gradual slipping of the adjustment mechanism during the load application, set the
backrest to its most rearward (stopped) position, then apply the specified load(s).
b) Remove the load.
7.4.2 Proof Load
a) A force of 1,112 N (250 lbf.) shall be applied to the backrest at the backstop position
for one (1) minute. If the backrest/tilt lock mechanism will not accept the load due to
gradual slipping of the adjustment mechanism during the load application, set the
backrest to its most rearward (stopped) position, then apply the specified load(s).
b) Remove the load.

7.5 Acceptance Level

7.5.1 Functional Load
A functional load applied once shall cause no loss of serviceability to the chair.
7.5.2 Proof Load
A proof load applied once shall cause no sudden and major change in the structural integrity of
the chair. Loss of serviceability is acceptable.

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 ANSI/BIFMA X5.11-2015

13 mm (0.5 in. ) ± 13mm (0.5 in.)

406 mm (16.0 in.)

diameter test bag.
See appendix A for
an example of one
acceptable bag
152 mm
(6 in.) 152 mm
(6 in.)

Figure 8 - Drop Test - Dynamic

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 ANSI/BIFMA X5.11-2015

8 Drop Test - Dynamic (See Figure 8)

8.1 Applicability
This test applies to all chair types.

8.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chair to withstand heavy and abusive
impact forces on the seat.

8.3 Test Setup

a) The unit shall be placed on a test surface. Note: Care should be taken not to perform
this test on platforms or other surfaces that may deform and/or lessen the impact.
b) For chairs with a seat height adjustment feature, set the adjustment to its highest
position. For chairs with glides that adjust greater than 50 mm (2.0 in), set them at 13
mm (0.5 in.) from their highest position. If other adjustable features are available, set
these adjustments at normal use conditions. Casters, if present, shall be initially placed
at the apparent worst-case position (typically at a position 90 degrees to the base leg).
Note: For chairs with lockable seat angles, the seat shall be tested in the unlocked
position.
c) A test bag containing metal media and/or sand shall be attached to a device permitting a
free fall to the seating position as shown in Figure 8.
d) The bag shall be centered side-to-side on the seat and shall be positioned 13 mm (0.5
in.) ± 13 mm (0.5 in.) from the most forward surface of the backrest during free fall (it is
acceptable for the bag to overhang the front of the seat in order to maintain the 13 mm
(0.5 in) clearance to the back). The bag shall not contact the backrest during the free
fall.

8.4 Test Procedures

8.4.1 Functional Load Test
a) A 406 mm (16 in.) diameter test bag weighing 113 kg (250 lb.) shall be raised 152 mm (6
in.) above the uncompressed seat and released one time. (See Figure 8).
b) Remove the bag.
c) For chairs with seat height adjustment features, set height to its lowest position and
repeat a) and b).

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 ANSI/BIFMA X5.11-2015

8.4.2 Proof Load Test

a) Repeat setup in 8.3 and increase the weight of the test bag to a proof load of 159 kg
(350 lb.).
b) The test bag shall be raised 152 mm (6 in.) above the uncompressed seat and released
one time. (See Figure 8).
c) Remove the bag.
d) For chairs with height adjustments, set seat height to its lowest position and repeat a)
through c). A second chair may be used for testing the chair in the lowest position.
Note: If a second chair is used for the proof load test, it must also be subjected to the
functional load impact per Section 8.4.1 while in its lowest position.

8.5 Acceptance Level

8.5.1 Functional Load
There shall be no loss of serviceability.
8.5.2 Proof Load
There shall be no sudden and major change in the structural integrity of the chair. Loss of
serviceability is acceptable.

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 ANSI/BIFMA X5.11-2015

Centerline of the weight

Centerline of rotational
axis

51-64 mm
(2.0 – 2.5 in.)

181 kg
(400 lb.)

Figure 9 - Swivel Test – Cyclic

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 ANSI/BIFMA X5.11-2015

9 Swivel Test - Cyclic (See Figure 9)

9.1 Applicability

This test applies to all chair types with a swivel seat.

9.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chair to withstand stresses and wear of
repeated swiveling.

9.3 Test Setup

a) The chair shall be restrained on a platform. Either the seat or the platform shall be
restrained from rotation. Figure 9 shows one acceptable method of restraint.
b) If the seat height is adjustable, set it to the maximum seat height position. Set all other
adjustable features to the normal use condition.
c) A 181 kg (400 lb.) load shall be placed on the seat such that the center of gravity of the
load is 51 to 64 mm (2 in. to 2.5 in.) forward of the centerline of the rotational axis as
shown in Figure 9.
d) The cycling device shall be adjusted to rotate the lesser of the following: the available
range of rotation or 360 degrees ± 10 degrees. If the available range of rotation is less
than 360 degrees, the rotation of the test machine shall be adjusted such that the swivel
mechanism touches but does not override the stops. The rotation may be either bi-
directional (alternating) or unidirectional.
e) For chairs that swivel 360 degrees, a cycle is one full rotation. For chairs that swivel
less than 360 degrees, one cycle is rotating from one stop to the other stop.

9.4 Test Procedure

a) The seat or platform shall rotate for 60,000 cycles at a rate between 5 and 15 rotations
per minute.
b) If the seat height is adjustable set the height to its lowest position.
c) For all chairs, continue the test for an additional 60,000 cycles to a total of 120,000
cycles.

9.5 Acceptance Level

There shall be no loss of serviceability.

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 ANSI/BIFMA X5.11-2015

Movement

159 kg (350 lb.)

Figure 10 - Tilt Mechanism Test - Cyclic

34
 ANSI/BIFMA X5.11-2015

10 Tilt Mechanism Test - Cyclic (See Figure 10)

10.1 Applicability
This test shall be performed on Type I and Type II chairs with tilting backrests.

10.2 Purpose of Test

The purpose of this test is to evaluate the ability of the tilt mechanism to withstand the fatigue
stresses and wear caused by repeated tilting.

10.3 Test Setup

a) The chair or fixture with attached tilt mechanism shall be restrained on a test surface.
Figure 10 shows one acceptable method of restraint.
b) If adjustable features are available, all adjustments shall be set at normal use conditions.
c) A cycling device shall be attached to the chair or fixture at any location appropriate to
apply a controlled (push and/or pull) motion.
d) A test load of 159 kg (350 lb.) shall remain on the center of the seat (or equivalent
location on the fixture) and secured if necessary.
e) Adjust the cycling device to move the mechanism between the front and back stops,
without overriding or impacting either stop.

10.4 Test Procedure

The unit shall be cycled for 300,000 cycles at a rate between 10 and 30 cycles per minute. The
tilt mechanism and/or cycling device should be checked and readjusted as needed to maintain
the original conditions specified.

10.5 Acceptance Level

There shall be no loss of serviceability to the tilt mechanism.

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 ANSI/BIFMA X5.11-2015

13 mm (0.5 in.) ± 13 mm (0.5 in.)

See Appendix A
for example of one
30 mm acceptable bag
(1.2 in.)
above un-
compressed
surface of
seat 30 mm
(1.2 in.) above
un-compressed
surface of seat

Figure 11a - Seating Durability Test - Cyclic

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 ANSI/BIFMA X5.11-2015

11 Seating Durability Tests – Cyclic (See Figures 11a and 11b)

Note: This is a two-part test. The impact test and front corner load-ease tests must be
run sequentially on the same sample for this evaluation.
11.1 Applicability
These tests apply to all chair types.

11.2 Purpose of Tests

The purpose of these tests is to evaluate the ability of chairs to withstand fatigue stresses and
wear caused by downward vertical force(s) on the seat.

11.3 Impact Test

11.3.1 Test Setup
a) The unit shall be placed on a test surface and be restrained in a manner that will
maintain the impact location on the seat. The method of restraint shall not add support
or structure to the chair, or inhibit movement of the chair response to the impact.
Casters, if present, shall be initially placed at the apparent worst-case position (typically
at a position 90 degrees to the base leg).
b) If adjustable features are available, all adjustments shall be set at normal use conditions.
For chairs with locking tilt mechanisms, the mechanism shall be placed in the unlocked
position.
c) Chairs with less than 44 mm (1.75 in.) of cushioning materials in the seat shall have
foam added to bring total cushioning thickness to 50 mm ± 6 mm (2 in. ± 0.25 in.). Any
additional foam added to the top of the seat shall have a 25% Indentation Force
Deflection (IFD) of 200 N ± 22 N (45 lbf. ± 5 lbf.).1
Note: Flexible seat surfaces (i.e., mesh, flexible plastic, etc.) are not considered
cushioning materials.
d) A 406 mm (16-inch) diameter test bag weighing 91 kg (200 lb.) shall be attached to a
cycling device, permitting a free fall to the seat as shown in Figure 11a. The free fall
shall begin after lifting the test bag 30 mm (1.2 in.) above the uncompressed surface on
the seat, as measured at the center of the seat. The drop height and/or seat height shall
be adjusted during the test if the drop height changes by more than 13 mm (0.5 in.). The
cycling device shall be set at a rate between 10 and 30 cycles per minute.
e) The bag shall be centered side-to-side on the seat and shall be positioned 13 mm (0.5
in.) ± 13 mm (0.5 in.) from the most forward surface of the backrest during free fall (it is
acceptable for the bag to overhang the front of the seat in order to maintain the 13 mm
(0.5 in.) clearance to the back). The bag shall not contact the backrest during the free
fall.
11.3.2 Test Procedure
The chair shall be tested to 100,000 cycles.

1 Specimen thickness 102 mm (4 in.). See Method B1, Indentation Force Deflection Test, in Standard Test Methods
for Flexible Cellular Materials —Slab, Bonded, and Molded Urethane Foams, ASTM D 3574.

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 ANSI/BIFMA X5.11-2015

Front of Chair Rear of Chair

254 mm ±13 mm
(10 in. ± 0.5 in.) Top View of Chair
Diameter loading
device

254 mm ± 13 mm
(10 in. ± 0.5 in.)
Load
Diameter loading
device

Figure 11b - Front Corner Load-Ease Test - Cyclic - Off-center

38
 ANSI/BIFMA X5.11-2015

11.4 Front Corner Load-Ease Test – Cyclic – Off-center

11.4.1 Test Setup

After completing the impact test in Section 11.3, apply a force of 1,334 N (300 lbf.)
through a 254 mm ± 13 mm (10 in. ± 0.5 in.) diameter loading device at one front corner
flush to each structural edge. If arms interfere with the placement of the loading device
and are intended to be removable, they shall be removed for this test. If arms interfere
but are not removable (or adjustable) the loading device shall be positioned to avoid
interference. If cushion material was used during impact testing (11.3.1c) it may remain
in place during this testing to avoid uneven/point loading of the seat.
11.4.2 Test Procedure
Raise the loading device from the seat and lower completely, without impact to the seat
so that it takes the entire load without any support from the cycling device, at a rate of 10
to 30 cycles per minute. Apply the loads in an alternating sequence to attain a total of
40,000 cycles.
Note: Another acceptable method of performing this test is to apply the load on one
front corner of the seat for 20,000 cycles then reposition the load to the other front
corner and perform the test for an additional 20,000 cycles.

11.5 Acceptance Level

There shall be no loss of serviceability to the chair after completion of both the impact
and load-ease tests.

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 ANSI/BIFMA X5.11-2015

Support Fixture
Material per
6 mm (0.24 in.) 12.3.1.1.e

Stability Disk: See

Appendix B for details

H (See 12.3.1.2.b) Per 12.3.1.1.c:

Restraining device
13 mm (0.5 in.) in
height

Figure 12a - Rear Stability Test for Type III Chairs

12 Stability Tests

12.1 Applicability
The stability tests shall be performed on all types of chairs.

Note: Rearward stability tests apply only to chairs with backrests greater than 200 mm (7.9 in.)
in height as measured with the CMD (See Section 3.5).

12.2 Purpose of Tests

The purpose of these tests is to evaluate the front and rear stability of chairs.

12.3 Rear Stability

12.3.1 Rear Stability Test for Type III Chairs (Figure 12a)
Note: If a chair needs to be tested as more than one type, it is recommended that it
be tested in the sequence given. If tested out of sequence (or individually by type)
all weights must be entirely removed from the chair before starting each test.
12.3.1.1 Test Setup
a) The chair shall be placed on a test surface.
b) For chairs with adjustable features, all adjustments shall be set at the apparent least
stable condition for rearward stability, such as:

40
 ANSI/BIFMA X5.11-2015

i) maximum height of seat or backrest, or both,

ii) rearmost seat or backrest position, or both,
iii) the least stable condition of casters or glides.
c) For chairs with casters, a block or obstruction 13 mm (0.5 in.) in height shall be affixed
to the test surface. The block shall prevent sliding but not interfere with the caster
hood such that it restricts the unit from tipping – in such cases, a lower height
obstruction may be used as long as it prevents sliding. On units that rotate, the bases
and casters, if any, shall be positioned to offer the least resistance to rearwards
tipping of the unit.
d) For chairs without casters, a block or obstruction 13 mm (0.5 in.) in height shall be
affixed to the test surface. On units that rotate, the base shall be positioned to offer
the least resistance to rearwards tipping of the unit.
Note: For chairs with tilt locks, locking the mechanism in the upright position
changes the chair type (See Section 4: Chair Type) and the chair shall be tested
in the locked (near upright) condition and in the unlocked (reclined) condition as
per Section 12.3.2.
e) Place a support fixture made of a 1.5 mm ± 0.4 mm (0.060 in. ± 0.015 in.) thick
polypropylene, 356 mm (14 in.) wide and 711 mm (28 in.) tall against the chair back
so that it approximates the contour of the back.

12.3.1.2 Test Procedure

a) Load the chair with 6 disks (See Appendix B). Place the first disk on the seat so it
touches the support fixture. As each disk is added to the stack slide it along the
lower disk until it contacts the support fixture as shown in Figure 12a. As each disk
is added, the backrest may move such that the lower disks do not remain against the
support fixture; this is acceptable, do not reposition the disks.
b) Apply a horizontal force to the highest disk. The location of the force application is 6
mm (0.25 in.) from the top of the disk. (See Figure 12a).
For chairs with seat height (as measured at the front of the bottom of the lowest disk
when all disks are in the chair) less than 710 mm (28.0 in.), calculate the force as
follows:
• F = 0.1964 (1,195 – H) Newton. H is the seat height in mm.
• [F = 1.1 (47 – H) pounds force]. H is the seat height in inches.
For chairs with seat height equal to or greater than 710 mm (28.0 in.), a fixed force of
93 N (20.9 lbf.) shall be applied.

12.3.1.3 Acceptance level

The chair shall not tip over.

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 ANSI/BIFMA X5.11-2015

Stability Disk: See

Appendix B for Details Support Fixture
Material per 12.3.2.1.c

Figure 12b - Rear Stability Test for Type I and II Chairs

42
 ANSI/BIFMA X5.11-2015

12.3.2 Rear Stability Test for Type I and II Chairs (Figure 12b)
Note: For chairs with tilt locks, locking the chair changes the chair type (See Section 4) and
must also be tested according to Section 12.3.1 in the upright locked position.
12.3.2.1 Test Setup
a) The chair shall be placed on a test surface. For chairs without casters, a block or
obstruction 13 mm (0.5 in.) in height shall be affixed to the test surface. On units that
rotate, the base shall be positioned to offer the least resistance to side tipping of the
unit.

b) On chairs with adjustable features, all adjustments shall be set at the apparent least
stable condition for rearward stability, such as:
a) maximum height of seat or backrest, or both,
b) minimum tension of tilt mechanism,
c) rearmost seat or backrest position, or both,
d) the least stable condition of casters or glides.

c) Place a support fixture made of a 1.5 mm ± 0.4 mm (0.060 in. ± 0.015 in.) thick
polypropylene, 356 mm (14 in.) wide and 711 mm (28 in.) tall against the chair back
so that it approximates the contour of the back.

12.3.2.2 Test Procedure

Load the chair with 13 disks (See Appendix B). Place the first disk on the seat so it touches the
support fixture. As each disk is added to the stack slide it along the lower disk until it contacts
the support fixture as shown in Figure 12b. As each disk is added, the backrest may move such
that the lower disks do not remain against the support fixture; this is acceptable, do not
reposition the disks. For tilting chairs that may remain upright when the load disks are applied,
gently apply a temporary force to move the chair to its full-tilt position or most rearward position
attained (i.e., at its tilt stop) as a result of the mass of the disks. Do not allow the momentum of
the mass to cause tipover of the chair. Care shall be taken that any additional rearward force
applied to position the chair in its most rearward position does not cause the chair to overturn –
only the mass in the chair at the tilt stop position shall determine the pass/fail condition of the
chair.
If the chair does not tip over and the tilt mechanism does not remain tilted as a result of the
additional force to position the chair at its most rearward position when the disks are placed in
the chair, the chair shall be tested according to 12.3.1 with the chair in the unlocked position.

12.3.2.3 Acceptance level

The chair shall not tip over.

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 ANSI/BIFMA X5.11-2015

79 kg
(175 lb.)

Load applied through

fixture (See Figure 12d)

Hold down
strap See Figure 12d

60 mm (2.4 in.) from

front edge of the load–
bearing surface Centerline of 20 N (4.5 lbf.)
seat

Figure 12c - Front Stability Test

44
 ANSI/BIFMA X5.11-2015

Sufficient to clear all

foam and fabric and
allow for setback

Sufficient to
Centerline to point clear all foam
and center of and fabric
gravity of weight

Total fixture
weight of 79
kg (175 lbs.)
19 mm (0.75 in) dia.
rod w/spherical tip

Figure 12d - Front Stability Loading Fixture

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 ANSI/BIFMA X5.11-2015

Optional - Carpet stretcher grip material on 300 mm (11.81 in.)

R surface. To be recessed into approximately a 2 mm (0.08 in.)
deep groove so that only the gripper teeth protrude. The carpet
gripper placement shown is one example, other configurations
are acceptable. Use of thin friction cloth / pads are also
acceptable.

Material – Nylon or
ABS
Weight to be 1.07 ± 0.40 kg
(2.36 ± 0.88 lb.)

Figure 12e - Stability Loading Disk

46
 ANSI/BIFMA X5.11-2015

79 kg
(175 lb.)

Load applied through

fixture (See Figure 12g)

60 mm (2.4 in.) from front

edge of the load-bearing
surface
20N (4.5 lbf.)
Centerline of seat

Figure 12f - Front Stability Test

Sufficient to clear all

foam and fabric and
allow for setback

Sufficient to
Centerline to point clear all foam
and center of gravity and fabric
of weight

Total Fixture
Weight of 79
kg (175 lbs.)
19 mm (0.75 in) dia.
rod with 45° taper

Figure 12g - Front Stability Loading Fixture

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 ANSI/BIFMA X5.11-2015

12.4 Front Stability

Front stability shall be determined by either the method described in Sections 12.4.1 and
12.4.2 or 12.4.1 and 12.4.3.
12.4.1 Test Setup
a) The unit shall be placed on a test surface.
b) On units with adjustable features, all adjustments shall be set at the apparent least
stable condition for forward stability, such as, maximum height of seat or backrest, or
both, most forward seat or backrest position or both, and at the least stable condition of
casters, glides and tilt mechanism.
c) For chairs with casters, a block or obstruction 13 mm (0.5 in.) in height shall be affixed to
the test surface. The device shall prevent sliding but not restrict the unit from tipping.
The block shall prevent sliding but not interfere with the caster hood such that it restricts
the unit from tipping – in such cases, a lower height obstruction may be used as long as
it prevents sliding. On units that rotate, the bases and casters, if any, shall be positioned
to offer the least resistance to forward tipping of the unit.
d) For chairs without casters, a block or obstruction 13 mm (0.5 in.) in height shall be
affixed to the test surface. On units that rotate, the base shall be positioned to offer the
least resistance to forward tipping of the unit.
12.4.2 Test Procedure (See Figures 12c and 12d).
a) Apply a vertical load of 79 kg (175 lb.), through the 200 mm (7.87 in.) diameter disk (See
Figure 12e for details). the center of which is 60 mm (2.4 in.) from the front center edge
of the load-bearing surface of the seat.
b) Apply a horizontal force of 20 N (4.5 lbf.) at the same height that the vertical force is
applied (at the point of contact of the loading fixture). The force shall be coincident with
the side-to-side centerline of the seat.
12.4.3 Test Procedure - Alternate (See Figures 12f and 12g)
a) This alternate method may be used on chairs that have a seat surface that will support
the stability loading fixture without the use of the 200 mm (7.87 in.) disk (i.e., hard
surfaced seats or seats with minimal cushion).
b) Apply a vertical load of 79 kg (175 lb.), by means of the front stability loading fixture
shown in Figure 12g at a point 60 mm (2.4 in.) from the front center edge of the load-
bearing surface of the chair.
c) Apply a horizontal force of 20 N (4.5 lbf.) at the height of the bottom of the load
application device. The force shall be coincident with the side-to-side centerline of the
seat.
12.4.4 Acceptance Level
The chair shall not tip over as the result of the force application.

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 ANSI/BIFMA X5.11-2015

DIRECTION OF FORCE: INITIALLY VERTICAL

127 ± 13 mm
(5 ± 0.5 in.) length

Restraint

Figure 13a - Arm Strength Test - Vertical – Static

Initial direction of
force to be vertical

Per 13.3c Loading

device must be 127
mm (5 in.) long and at
least as wide as the
arm width

Per 13.3d Pivot

distance must
be 762 mm (30
in.) or greater

Figure 13b - Arm Strength Test - Vertical – Static

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 ANSI/BIFMA X5.11-2015

Initial direction of force

to be vertical

Not greater than

50 mm (2 in.)
above the top of
the armrest Per 13.3c Loading
device must be 127
mm (5 in.) long and at
least as wide as the
arm width

Per 13.3d Pivot

distance must be
762 mm (30 in.) or
greater

Figure 13c - Arm Strength Test - Vertical – Static (“C” Fixture Method)

13 Arm Strength Test - Vertical - Static (See Figures 13a, 13b, and 13c)

13.1 Applicability
This test applies to all chairs with arms.

13.2 Purpose of Test

The purpose of the test is to evaluate the ability of a chair and arm to withstand stresses caused
by applying vertical forces on the arm(s).

13.3 Test Setup

a) The chair shall be placed on a test surface and restrained from movement, including
rotational movement of the seat. Blocking movement of the chair shall not provide a
counterbalancing force. Type III chairs may be restrained using the seating surface (see
Figure 13a)
b) If adjustable features are available, all adjustments shall be set at normal use conditions.

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 ANSI/BIFMA X5.11-2015

c) A loading adapter that is 127 mm (5 in.) long and at least as wide as the width of the arm
shall be attached to the top of the arm rest structure such that the load will be applied at
the apparent weakest point that is forward of the front of the chair’s backrest (at the
height of the top of the armrest).
d) Apply an initially vertical pull force to the load adapter using a mechanism, such as a
cable and pulley, having a pivot point 762 mm (30 in.) or greater below the arm. The
attachment to the load adapter shall not be greater than 50 mm (2 in.) above the top of
the armrest (See Figure 13b). The mechanism must allow the arm to deflect or pivot as a
result of the load application. If the chair design does not allow pull force application,
other methods of applying the load are acceptable as long as they allow the arm to
deflect or pivot as a result of the load application.

13.4 Test Procedures

13.4.1 Functional Load
a) A force of 890 N (200 lbf.) shall be applied for one (1) minute.
b) Remove the force.
13.4.2 Proof Load
a) A force of 1,334 N (300 lbf.) shall be applied for one (1) minute.
b) Remove the force.

13.5 Acceptance Level

13.5.1 Functional Load
There shall be no loss of serviceability. For a height adjustable arm, failure to hold its height
adjustment position to within 6 mm (0.25 in.) from its original set position as the result of the
loading is considered a loss of serviceability.

13.5.2 Proof Load

There shall be no sudden and major change in the structural integrity of the chair. For a height
adjustable arm, a sudden drop in height of greater than 25 mm (1 in.) does not meet this
requirement. Loss of serviceability is acceptable.

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 ANSI/BIFMA X5.11-2015

Pivot distance must

be 762 mm (30 in.)
or greater

Figure 14 - Arm Strength Test - Horizontal - Static

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 ANSI/BIFMA X5.11-2015

14 Arm Strength Test - Horizontal - Static (See Figure 14)

14.1 Applicability
This test applies to all chairs with arms.

14.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chair to withstand stresses caused by
applying outward forces to the arm(s).

14.3 Test Setup

a) The chair shall be placed on a test surface. Restrain the chair from horizontal
movement and tipping including rotational movement of the seat. Blocking movement of
the chair shall not provide a counterbalancing force. The restraints shall not restrict the
chair arm movement. Figure 14 shows one acceptable method of restraining the chair.
b) If adjustable features are available, all adjustments shall be set at normal use conditions.
c) A loading device or strap, not greater than 25 mm (1 in.) in horizontal width, shall be
attached to the arm so that the load is initially applied horizontally to the armrest
structure at the apparent weakest point. For armrests that pivot in the horizontal plane,
apply the load at the pivot point.
d) Apply an initially horizontal pull force to the load adapter using a mechanism such as a
cable and pulley or other mechanism having a pivot point 762 mm (30 in.) or greater
from the arm. The mechanism must allow the arm to deflect as a result of the load
application.

14.4 Test Procedures

14.4.1 Functional Load
a) A force of 445 N (100 lbf.) shall be applied for one (1) minute in the outward direction.
b) Remove the force.
14.4.2 Proof Load
a) A force of 667 N (150 lbf.) shall be applied for one (1) minute in the outward direction.
b) Remove the force.

14.5 Acceptance Level

14.5.1 Functional Load

A functional load applied once shall cause no loss of serviceability.

14.5.2 Proof Load

A proof load applied once shall cause no sudden and major change in the structural integrity of
the unit. Loss of serviceability is acceptable.

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Height above seat

using scale on CMD

Figure 15a - Test Height Determination

Backrest Durability Test - Type I

Form-fitting device

406 mm (16.0 in.)

Figure 15b - Positioning of Form-Fitting Device for Backrests Higher than 452 mm (17.8
in.) Backrest Durability Test - Type I

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 ANSI/BIFMA X5.11-2015

Form-fitting device

Less than 452 mm (17.8 in.)

height above seat

Device even with

top of back

Figure 15c - Positioning of Form-Fitting Device for Backrests Lower than 452 mm (17.8
in.) Backrest Durability Test - Type I

>20°

Pivot point of
pivoting – type back

159 kg (350 lb.) 445 N

(100 lbf.)

Direction of force
application (backrest
90°± 10° in its most backrest
position)

Figure 15d - Force Application for Backrests that Pivot Greater than 20°
Backrest Durability Test - Cyclic - Type l

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 ANSI/BIFMA X5.11-2015

445 N
Position per 15.3 (100 lbf.)

Direction of force
application (backrest
in its most rearward
90°± 10° position)
159 kg (350 lb.)

Figure 15e - Force Application for All Other Backrests

Backrest Durability Test - Cyclic

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 ANSI/BIFMA X5.11-2015

15 Backrest Durability Test - Cyclic - Type l (See Figures 15a through 15e)

15.1 Applicability
This test shall be performed on Type I Tilting chairs.
Note: This test does not apply to chairs with backrest height less than 200 mm (7.9 in.).

15.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chairs to withstand fatigue stresses and
wear caused by rearward force on the backrest of the chair.

15.3 Test Setup

15.3.1 The chair shall be placed on a test surface in an upright position with the base/legs
restrained from movement. If pushing on the backrest with the test device, the chair
must be restricted from rotating. Clamping shall be done so as not to restrict the
movement of the backrest(s) or arm(s) of the chair.
15.3.2 If adjustable features are available, all adjustments shall be set at normal use conditions.
Note: For chairs with tilt mechanisms that lock, locking the mechanism changes the
classification of the chair. (See Section 4). Chairs with tilt mechanisms in an unlocked
position shall be tested according to this section and an additional chair shall also be
tested according to Section 16. When testing in accordance with Section 16, the chair
shall be tested in the upright locked position.
15.3.3 Determine points 406 mm (16 in.) and 452 mm (17.8 in.) above the seat (See Section
3.5). Mark these points on the vertical centerline of the backrest.
a) If the top of the load-bearing structure/surface of the backrest is greater than or equal to
452 mm (17.8 in.) above the seat, position the center of the form-fitting device (See
Definition 2.9) 406 mm (16 in.) above the seat. (See Figure 15b).
b) If the top of the load-bearing structure/surface of the backrest is less than 452 mm (17.8
in.) above the seat, position the top of the form-fitting device even with the top of the
load-bearing structure/surface. (See Figure 15c).
c) If the unit has a pivoting backrest that stops at a position less than or equal to 20
degrees rearward of vertical (with the support structure in its most upright position),
position the form-fitting device as directed in a) or b). If the unit has a pivoting backrest
that stops at a position greater than 20 degrees rearward of vertical (with the support
structure in its most upright position), position the center of the form-fitting device at the
height of the pivoting point. (See Figure 15d).

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 ANSI/BIFMA X5.11-2015

15.3.4 Attach a loading device (front push or back pull) to the horizontal center of the backrest
as determined above. With the backrest at its back stop position, apply a force that is
initially 90 degrees ± 10 degrees to the plane of the backrest. The force is not intended
to be maintained at 90 degrees ± 10 degrees throughout the loading of the backrest. If
applying the load with a cable and pulley system, the cable must initially be a minimum
of 762 mm (30 in.) in length from the attachment point to the pulley.
Note: Where the design of the chair does not allow the transfer of force(s) from the form-
fitting device to the load-bearing structure/surface, then a bridging device 38 mm to 102
mm (1.5 in. to 4 in.) in height may be used to span the width of the load-bearing
structure/surface. The plane of the backrest may be defined by the front of the CMD
upright. (See Figure 15a).
15.3.5 A weight of 159 kg (350 lb.) shall remain in the center of the seat and be secured if
necessary. (See Figures 15d and 15e).
15.3.6 The loading device shall be adjusted to apply a 445 N (100 lbf.) total force to the
backrest. (See Figure 15e).
15.3.7 The loading device shall be set at a rate between 10 and 30 cycles per minute.

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Top View: Seat Back

Offset from
Centerline per
15.4.2

445 N (100 lbf.)

Form-fitting Device

Figure 15f - Off-center Backrest Durability Loading - Left

Top View: Seat Back

445 N (100 lbf.)

Centerline of
Seat Back

Offset from Centerline

per 15.4.2
Form-fitting Device

Figure 15g - Off-center Backrest Durability Loading - Right

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15.4 Test Procedures

15.4.1 For chairs with backrest widths less than or equal to 406 mm (16 in.) at the height of the
loading point, apply the load to the backrest for 120,000 cycles.
15.4.2 For chairs with backrest widths greater than 406 mm (16 in.) at the height of the loading
point, apply the load to the backrest for 80,000 cycles.
a) Keeping the load at the height determined above, reposition the load 25% of the
backrest width rounded to the nearest 25 mm (1 inch) increment (at the 16 in height)
to the right of the vertical centerline. The load may be applied through a form-fitting
device if necessary. (See Figure 15f and 15g). With the backrest at its back stop
position, apply a force that is initially 90 degrees ± 10 degrees to the plane of the
backrest. The force is not intended to be maintained at 90 degrees ± 10 degrees
throughout the loading of the backrest. If applying the load with a cable and pulley
system, the cable must initially be a minimum of 762 mm (30 in.) in length from the
attachment point to the pulley. Apply this load for 20,000 cycles.
b) Keeping the load at the height determined above, reposition the load 25% of the
backrest width rounded to the nearest 25 mm (1 inch) increment (at the 16 in height)
to the left of the vertical centerline. The load may be applied through a form-fitting
device if necessary. (See Figure 15f and 15g). With the backrest at its back stop
position, apply a force that is initially 90 degrees ± 10 degrees to the plane of the
backrest. The force is not intended to be maintained at 90 degrees ± 10 degrees
throughout the loading of the backrest. If applying the load with a cable and pulley
system, the cable must initially be a minimum of 762 mm (30 in.) in length from the
attachment point to the pulley. Apply this load for 20,000 cycles.

15.5 Acceptance Level

There shall be no loss of serviceability.

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 ANSI/BIFMA X5.11-2015

Height above seat

using scale on CMD

Figure 16a - Test Height Determination

Backrest Durability Test - Type Il and lll

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 ANSI/BIFMA X5.11-2015

Form-fitting Device

406 mm (16.0 in.)

Figure 16b - Positioning of Form-Fitting Device for Backrests Higher than 452 mm (17.8
in.) Backrest Durability Test - Type Il and lll

Form-fitting Device

Less than 452 mm (17.8 in.)

height above seat.
Device even with
top of back.

Figure 16c - Positioning of Form-Fitting Device for Backrests Lower than 452 mm (17.8
in.) Backrest Durability Test - Type Il and lll

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 ANSI/BIFMA X5.11-2015

> 20°

Pivot point of
pivoting-type back

334 N
159 kg (350 lb.) (75 lbf.)

Direction of force
application (backrest
in its most backrest
90°± 10° position)

Figure 16d - Force Application for Backrests that Pivot Greater than 20 Degrees
Backrest Durability Test - Cyclic - Type Il and lll

334 N
(75 lbf.)

Position per 16.3

Direction of force
90°± 10° application (backrest
in its most rearward
position)
159 kg (350 lb.)

Figure 16e - Force Application for All Other Backrests

Backrest Durability Test - Cyclic - Type Il and lll

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16 Backrest Durability Test - Cyclic - Type Il and lll (See Figures 16a through 16g)

16.1 Applicability
This test shall be performed on Type Il and lll chairs.

Note: This test does not apply to chairs with backrest height less than 200 mm (7.9 in.).

16.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chairs to withstand fatigue stresses and
wear caused by rearward force on the backrest of the chair.

16.3 Test Setup

16.3.1 The chair shall be placed on a test surface in an upright position with the base/legs
restrained from movement. If pushing on the backrest with the test device, the chair
must be restricted from rotating. Clamping shall be done so as not to restrict the
movement of the backrest(s) or arm(s) of the chair.

16.3.2 If adjustable features are available, all adjustments shall be set at normal use conditions.
16.3.3 Determine points 406 mm (16 in.) and 452 mm (17.8 in.) above the seat (See Section
3.5). Mark these points on the vertical centerline of the backrest.
a) If the top of the load-bearing structure/surface of the backrest is greater than or equal
to 452 mm (17.8 in.) above the seat, position the center of the form-fitting device
(See Definition 2.9) 406 mm (16 in.) above the seat. (See Figure 16b).
b) If the top of the load-bearing structure/surface of the backrest is less than 452 mm
(17.8 in.) above the seat, position the top of the form-fitting device even with the top
of the load-bearing structure/surface. (See Figure 16c).
c) If the unit has a pivoting backrest that stops at a position less than or equal to 20
degrees rearward of vertical (with the support structure in its most upright position),
position the form-fitting device as directed in a) or b). If the unit has a pivoting
backrest that stops at a position greater than 20 degrees rearward of vertical (with
the support structure in its most upright position), position the center of the form-
fitting device at the height of the pivoting point. (See Figure 16d).

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16.3.4 Attach a loading device (front push or back pull) to the horizontal center of the backrest
as determined above. With the backrest at its back stop position, apply a force that is
initially 90 degrees ± 10 degrees to the plane of the backrest. The force is not intended
to be maintained at 90 ± 10 degrees throughout the loading of the backrest. If applying
the load with a cable and pulley system, the cable must initially be a minimum of 762
mm (30 in.) in length from the attachment point to the pulley.
Note: Where the design of the chair does not allow the transfer of force(s) from the form-
fitting device to the load-bearing structure/surface, then a bridging device 38 mm
to 102 mm (1.5 in. to 4 in.) in height may be used to span the width of the load-
bearing structure/surface. The plane of the backrest may be defined by the front
of the CMD upright. (See Figure 16a).
16.3.5 A weight of 159 kg (350 lb.) shall remain in the center of the seat and be secured if
necessary. (See Figure 16d and 16e).
16.3.6 The loading device shall be adjusted to apply a 334 N (75 lbf.) total force to the backrest.
If the backrest/tilt lock mechanism will not accept the load due to gradual slipping of the
adjustment mechanism during the load application, set the backrest to its most rearward
(stopped) position, then apply the specified load(s).
16.3.7 The loading device shall be set at a rate between 10 and 30 cycles per minute.

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Top View: Seat Back

Offset from
Centerline per
16.4.2

334 N (75 lbf.)

Form-fitting device

Figure 16f - Off-center Backrest Durability Loading - Left

Top View: Seat Back

334 N (75 lbf.)

Centerline of Seat Back

Offset from Centerline

Form-fitting Device per 16.4.2

Figure 16g - Off-center Backrest Durability Loading - Right

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16.4 Test Procedures

16.4.1 For chairs with backrest widths less than or equal to 406 mm (16 in.) at the height of the
loading point, apply the load to the backrest for 120,000 cycles.
16.4.2 For chairs with backrest widths greater than 406 mm (16 in.) at the height of the loading
point, apply the load to the backrest for 80,000 cycles.
a) Keeping the load at the height determined above, reposition the load 25% of the
backrest width rounded to the nearest 25 mm (1 inch) increment (at the 16 in height)
to the right of the vertical centerline (See Figure 16f and 16g). With the backrest at
its back stop position, apply a force that is initially 90 degrees ± 10 degrees to the
plane of the backrest. The force is not intended to be maintained at 90 degrees ± 10
degrees throughout the loading of the backrest. If applying the load with a cable and
pulley system, the cable must initially be a minimum of 762 mm (30 in.) in length
from the attachment point to the pulley. Apply this load for 20,000 cycles.
b) Keeping the load at the height determined above, reposition the load 25% of the
backrest width rounded to the nearest 25 mm (1 inch) increment (at the 16 in height)
to the left of the vertical centerline (See Figure 16f and 16g). With the backrest at its
back stop position, apply a force that is initially 90 degrees ± 10 degrees to the plane
of the backrest. The force is not intended to be maintained at 90 degrees ± 10
degrees throughout the loading of the backrest. If applying the load with a cable and
pulley system, the cable must initially be a minimum of 762 mm (30 in.) in length
from the attachment point to the pulley. Apply this load for 20,000 cycles.

16.5 Acceptance Level

There shall be no loss of serviceability.

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 ANSI/BIFMA X5.11-2015
3.2 mm
Length of threshold indicated 51 mm (0.125 in.)
in figure below (2 in.)

Material: Steel
8 mm N 3.2 mm R ± 0.4 mm
(0.313 in.)
(0.125 in. ± 0.016 in.)
Figure 17a - Obstacle Detail Typical All Sides

432 mm
(17 in.)

A = Sufficient distance
such that casters
Centerline always pass over
of travel straight sections of the
obstacles.

B = A/2

210 mm 455 mm
(8.25 in.) (17.5 in.)

762 +/- 50 mm (30 +/- 2 in.)

Stroke Length based on centerline of chair

Figure 17b - Obstacle Layout for Pedestal Base Chairs

Load: See Section 17.1.3c)

Figure 17c - Machine Schematic for Pedestal Base Chairs

Figures 17a through 17c - Caster/Chair Base Durability Test - Cyclic

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 ANSI/BIFMA X5.11-2015

17 Caster/Chair Base Durability Test - Cyclic (See Figures 17a through 17e)

17.1 Caster/Chair Base Durability Test for Pedestal Base Chairs

17.1.1 Applicability
This test applies to pedestal base chairs with casters.
17.1.2 Purpose of Test
The purpose of this test is to evaluate the ability of the chair base and casters to withstand
fatigue stresses and wear caused by moving the chair back and forth.
17.1.3 Test Setup
a) The chair, or chair base with casters, shall be attached to a cycling device similar to
Figure 17c. When testing a full chair, set all adjustments to midpoint.
b) The chair shall be cycled on smooth, hard surface (steel preferred) with three obstacles
as shown in Figure 17a in accordance with the obstacle layout as shown in Figure 17b.
c) If a complete chair is to be tested, place a 181 kg (400 lb.) load on the seat of the chair.
If a fixture is used, the weight of the test assembly (base assembly, fixture and weights)
shall be equivalent to 181 kg (400 lb.) plus the weight of the chair in its fully assembled
configuration. (See Figure 17c). The base and casters shall be free to rotate and
swivel.
d) The stroke of the cycling device shall be adjusted to 762 +/- 50 mm (30 +/- 2 in.) of
travel. The stroke shall be oriented so the casters roll across the test surface and
obstacles as shown in Figure 17b.
e) The cycling device shall be operated at a rate of 10 ± 2 cycles per minute. One cycle
shall consist of a forward and backward stroke of the cycling device.
f) For units with caster and glide combinations, the legs without casters may be raised a
maximum of 51 mm (2 in.) above the test platform (supported by the attachment device)
during this test. The casters shall be free to rotate and swivel where applicable. There
shall be no load placed on the seat of the unit or unit base.

17.1.4 Test Procedure

a) The chair or chair base shall be cycled 2,000 cycles over the obstacles as shown in
Figure 17b and then 98,000 cycles on a smooth, hard surface (steel preferred) without
obstacles.
b) Evaluate the product in accordance with the acceptance level in 17.1.5.1.
c) At the conclusion of cycling, a 22 N (5 lbf.) pull force shall be applied to each caster in
line with the caster stem centerline.
d) Evaluate the product in accordance with the acceptance level in 17.1.5.2.

17.1.5 Acceptance Level

There shall be no loss of serviceability. No part of the caster shall separate from the chair as a
result of the application of the 22 N (5 lbf.) force.

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 ANSI/BIFMA X5.11-2015

Centerline 90°
of travel

Sufficient distance such that

the casters always pass over
the obstacles.

Figure 17d - Obstacle Layout for Chairs with Legs

181 kg (400 lb.) Load

200-400 mm
(8-15.5 in.) STROKE LENGTH 200-400 mm
762 +/- 50 mm (30 +/- 2 in.) (8-15.5 in.)
Figure 17e – Machine Schematic for Chairs with Legs

Figure 17d & 17e Caster/Chair Base Durability Test - Cyclic

Obstacle Layout and Machine Stroke

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 ANSI/BIFMA X5.11-2015

17.2 Caster/Chair Frame Durability Test for Non-pedestal Chairs with Casters

17.2.1 Applicability
This test applies to chairs with legs and casters. This test is not applicable to chairs with
glide/caster combinations (i.e., those having two glides and two casters).

17.2.2 Purpose of Test

The purpose of this test is to evaluate the ability of the chair frame and casters to withstand
fatigue stresses and wear caused by moving the chair back and forth.

17.2.3 Test Setup

a) The chair, or chair frame with casters, shall be attached to a cycling device similar to
Figure 17e. The cycling device shall be attached to apply the horizontal motion at the
highest point that does not cause the chair to tip or lift the casters entirely off the surface
during the test but not any higher than 25 mm (1 in.) above the bottom of the applied
weight. The attachment point may span one set of legs if necessary, but should not
span all legs or add additional structure to the chair (other than the spanned legs).
b) The chair shall be cycled on a smooth, hard surface (steel preferred) with two obstacle
layout as shown in Figure 17d and 17e in accordance with the obstacle detail as shown
in Figure 17a.
c) Place and secure a distributed 181 kg (400 lb.) on the center of seat of the chair. The
casters shall be free to rotate and swivel.
Note: Some chairs of this type have fixed rear casters. If that is the case, the casters
should roll freely.
d) The stroke of the cycling device shall be adjusted to 762 +/- 50 mm (30 +/- 2 in.) of
travel. The stroke shall be set and the obstacles shall be oriented such that the casters
roll across the test surface and obstacles, and that each caster travels beyond the
obstacle by 200 to 400 mm (8 to 15.5 in.) in each direction as shown in Figure 17e.
During one cycle, each caster shall cross a threshold twice (once in the forward direction
and once in the return direction); the obstacles shall be spaced such that the leading and
following sets of casters do not cross the thresholds simultaneously.
e) The cycling device shall be operated at a rate of 10 ± 2 cycles per minute. One cycle
shall consist of a forward and backward stroke of the cycling device.

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 ANSI/BIFMA X5.11-2015

17.2.4 Test Procedure

a) The chair or chair base shall be cycled for 2,000 cycles over the obstacles as shown in
Figures 17d and 17e and then 98,000 cycles on a smooth, hard surface (steel
preferred) without obstacles.
b) Evaluate the product in accordance with the acceptance level in 17.2.5.
c) At the conclusion of cycling, a 22 N (5 lbf.) pull force shall be applied to each caster in
line with the caster stem centerline.

17.2.5 Acceptance Level

There shall be no loss of serviceability. No part of the caster shall separate from the chair as a
result of the application of the 22 N (5 lbf.) force.

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 ANSI/BIFMA X5.11-2015

Side view

Per 18.3.1a:
Direction Restraining device
of force 11 to 38 mm (0.44
to 1.50 in.) in
height

13 mm - 38 mm (0.5 in. -1.5 in.)

Figure 18a - Leg Strength Test - Front Application

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 ANSI/BIFMA X5.11-2015

Front view

Per 18.4.1a:
Restraining device
11 to 38 mm (0.44
Direction to 1.50 in.) in
of force height

13 mm (0.5 in.) – 38 mm (1.5 in.)

Figure 18b - Leg Strength Test - Side Application

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 ANSI/BIFMA X5.11-2015

18 Leg Strength Test - Front and Side Application (See Figure 18a & 18b)
18.1 Applicability
This test applies to all chairs without pedestal bases.
18.2 Purpose of Test
The purpose of this test is to evaluate the ability of legs to withstand horizontal side and frontal
forces.

18.3 Front Load Test

18.3.1 Test Setup
a) The chair shall be placed on a test surface, with the back legs restrained by a block 11
to 38 mm (0.44 to 1.50 in.) high. Figure 18a shows one acceptable method of
restraining the chair.
b) If adjustable features are available, all adjustments shall be set at normal use conditions.
c) The loading device shall be attached to the chair so that an initially horizontal force is
applied inward and parallel to the front-to-rear axis of the chair, between 13 mm (0.5 in.)
and 38 mm (1.5 in.) from the bottom of a leg as shown in Figure 18a. For chairs with
casters, apply the load to the chair leg, but not more than 13 mm (0.5 in.) from the point
of caster attachment (bottom of the leg). The load shall be applied to the apparent
weakest point of the leg. Where the apparent weakest point is the left or right edge of
the leg, apply the load so that it is no greater than 25 mm (1.0 in.) from the edge.

18.3.2 Test Procedures

18.3.2.1 Functional Load Test
a) A force of 445 N (100 lbf.) shall be applied once to each front leg individually for one
(1) minute. Note: If front legs are of identical construction, then only one leg is to be
tested.
b) Remove the force.
18.3.2.2 Proof Load Test
a) A force of 667 N (150 lbf.) shall be applied once to each front leg individually for one
(1) minute. Note: If front legs are of identical construction, then only one leg is to be
tested.
b) Remove the force.

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18.4 Side Load Test

Note: A separate chair may be used for the side load portion of the test.
18.4.1 Test Setup
a) The chair shall be placed on a test surface with the side leg(s) restrained by a block 11
to 38 mm (0.44 to 1.50 in.) high. Figure 18b shows one acceptable method of
restraining the chair.
b) If adjustable features are available, all adjustments shall be set at normal use conditions.
c) The loading device shall be attached to the chair so that an initially horizontal force is
applied inward and parallel to the side-to-side axis of the chair, between 13 mm (0.5 in.)
and 38 mm (1.5 in.) from the bottom of a leg as shown in Figure 18b. For chairs with
casters, apply the load to the chair leg, but not more than 13 mm (0.5 in.) from the point
of caster attachment (bottom of the leg). The load shall be applied to the apparent
weakest point (front-to-back) of the leg. Where the apparent weakest point is the front or
rear edge of the leg, apply the load so that it is no greater than 25 mm (1.0 in.) from the
edge.
18.4.2 Test Procedure
18.4.2.1 Functional Load Test
a) A force of 445 N (100 lbf.) shall be applied once to a front and rear leg individually for
one (1) minute. Note: If side legs are of identical construction, then only one set of
side legs is to be tested.
b) Remove the force.
18.4.2.2 Proof Load Test
a) A force of 667 N (150 lbf.) shall be applied once to a front and rear leg individually for
one (1) minute. Note: If side legs are of identical construction, then only one set of
side legs is to be tested.
b) Remove the force.

18.5 Acceptance Level - Front and Side Load Tests

18.5.1 Functional Load

Functional load(s) applied once in each direction shall cause no loss of serviceability.

18.5.2 Proof Load

Proof load(s) applied once each direction shall cause no sudden and major change in the
structural integrity of the chair. Loss of serviceability is acceptable.

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Not greater than 25

mm (1 in.)

33 mm R (1.3 in.)

Armpad
50 mm
(2 in.) min.

100 mm (4 in.)

30°

Figure 19a - Arm Loading Device

10°±1°
10°±1°

Application distance:
600 mm ± 10 mm
(23.6 in. ± 0.4 in.)

444 N (100 lbf.)

Other methods of
applying the load
are acceptable if the
force and angle
applications are
equivalent.

Figure 19b - Arm Durability Test - Cyclic

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19 Arm Durability Test - Cyclic (Figure 19a and 19b)

19.1 Purpose of test

The purpose of this test is to evaluate the ability of the chair armrests to withstand stresses that
occur as a result of repetitive loading that can be imposed on the armrest structure. Loading of
this type is the result of using the armrests as a support when getting into or out of the chair.

19.2 Test setup

a) The chair shall be placed on a test surface in an upright position as shown in Figure 19b.
If necessary, the seat may be restrained from rotational movement. Clamping shall be
done in such a manner as not to restrict the arms of the unit.
b) Height-adjustable arms must be set at the apparent weakest position. When the
weakest position is not obvious, several load applications positions may be necessary to
properly test the product.
c) Width-adjustable arms must be set at the apparent weakest position.
d) Unrestrained pivoting armrests (i.e., the armrest cap pivots freely) shall be loaded in line
with the pivot point.
e) The arm loading device should distribute the load over a length of 100 mm (4 in.) on the
arm pad. Center of load shall not be applied more than 25 mm (1.0 in.) in from the
inside edge of the arm pad. One suggested arm loading device is shown in Figure 19a.
Position the arm loading device on the armrest structure at its apparent weakest point
consistent with using the armrest as a support for entering or exiting the chair.

19.3 Test procedure

Simultaneously apply a force of 444 N (100 lbf.) to each arm initially at a 10 degrees ± 1 degree
angle as shown in Figure 19b. The arm loading device must follow the arm (allow fore and aft,
side-to-side and rotational movement) as it deflects or pivots. The fixture linking the arm loading
device to the armrest pad shall stay in contact with the arm pad throughout the loading cycle. If
using a test device similar to that shown in Figure 19b, the load application distance must
initially be the length specified in the figure. Other methods of applying the load are acceptable
if the force and angle applications are equivalent. The force shall be applied and removed for
60,000 cycles at a rate between 10 and 30 cycles per minute.

19.4 Acceptance level

There shall be no loss of serviceability to the chair.

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74 kg (163 lb.)

Direction of movement

25 kg (55 lb.)

Figure 20 - Out Stop Test for Chairs with Manually Adjustable Seat Depth

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20 Out Stop Tests for Chairs with Manually Adjustable Seat Depth (See Figure 20)

20.1 Purpose of Test

The purpose of this test is to evaluate the ability of the seat slide out stops to withstand
excessive impact forces that may result from user adjustment of the seat depth.
Note: This test does not apply to chairs where seat depth adjustments must occur with the user
out of the chair.

20.2 Test Setup

a) The chair shall be placed on a test surface and restrained to prevent it from moving.
The method of securing shall not interfere with the operation of the seat slide being
tested. For chairs with an adjustable seat angle, set the angle to its most forward
(negative seat slope) angle. Disable any seat depth adjustment locks or interim stops.
b) A stranded metallic cable or equivalent shall be attached to the most rigid point of the
vertical centerline of the seat. This may be accomplished by means of a clamp or similar
device that does not affect the test results.
c) The opposite end of the cable shall extend in line forward from the seat and in line with
the plane of the seat movement to a pulley and then downward to an attached weight of
25 kg (55 lb.). Place the seat in its most rearward position and restrain.
d) Place a 74 kg (163 lb.) rigid mass in the center of the seat.

20.3 Test Procedure

The seat with the hanging weight shall be held at its most rearward position, then released,
permitting it to move forward rapidly and impact the out stops. Repeat this procedure for a total
of 25 cycles.

20.4 Acceptance Level

There shall be no loss of serviceability to the unit.

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Location of the 203 mm

(8 in.) disk
68 kg (150 lb.) Load
25 mm
(1in.)

25 mm
Top View (1in.)

Figure 21 - Tablet Arm Chair Static Load Test

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21 Tablet Arm Chair Static Load Test (See Figure 21)

21.1 Purpose of Test

The purpose of this test is to evaluate the ability of the unit equipped with a tablet arm or other
attached auxiliary writing/laptop surface to withstand stresses caused by vertical loading.

21.2 Test Setup

a) The unit shall be placed on a test platform and restrained to prevent movement. Any
height adjustment of the chair and/or tablet arm shall be set at the midpoint of
adjustment.
b) Apply the load through a 203 mm ± 13 mm (8.0 in. ± 0.5 in.) diameter area 25 mm (1 in.)
from the edge of the surface at its apparent weakest point. When the weakest point is
not obvious, several load applications may be necessary to properly test the product. If
required to prevent tipping of the chair, a counterbalancing force may be applied to the
chair seat.

21.3 Test Procedure

Apply a load of 68 kg. (150 lb.) at the location described in 21.2 b) for one (1) minute and
remove the load.

21.4 Acceptance Level

The load applied once shall cause no sudden and major change in the structural integrity of the
chair. After performing the test, the tablet arm must allow egress from the unit; other losses of
serviceability are acceptable.

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Location of the 203 mm

(8 in.) disk 25 kg (55 lb.)
Load
25 mm
(1in.)

25 mm
Top View (1 in.)

Figure 22 - Tablet Arm Chair Load Ease Test - Cyclic

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22 Tablet Arm Chair Load Ease Test - Cyclic (See Figure 22)
22.1 Purpose of Test
The purpose of this test is to evaluate the durability of the tablet arm chair to withstand cyclic
loading of the tablet.

22.2 Test Setup

a) The unit shall be leveled in its normal operating position. The unit shall be placed on a
test surface and restrained to prevent movement. Any height adjustment of the chair
and/or tablet arm shall be set at the midpoint of adjustment.
b) Apply a load of 25 kg (55 lb.) through a 203 mm ± 13 mm (8.0 in. ± 0.5 in.) diameter area
25 mm (1 in.) from the edge of the surface at its apparent weakest point. When the
weakest point is not obvious, several load applications may be necessary to properly
test the product. If required to prevent tipping of the chair, a counterbalancing force may
be applied to the chair seat.
c) The cycling device shall be set to operate at a rate of 14 ± 6 cycles per minute.

22.3 Test Procedure

a) The load shall be raised until the entire load is off the tablet surface and then eased
(without impact) onto the surface, so that it takes the entire load without any support
from the cycling device.
b) Repeat Step (a) for a total of 100,000 cycles.

22.4 Acceptance Level

There shall be no loss of serviceability to the unit.

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Front view

159 kg (350 lb.)

in the seat

Direction
Restraining of force
devices 11 to
38 mm (0.44
to 1.50 in.) in
height

Figure 23 - Structural Durability Test – Cyclic

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23 Structural Durability Test - Cyclic (See Figure 23)

23.1 Applicability
This test shall does not apply to pedestal-base chairs or chairs with casters.

23.2 Purpose of Test

The purpose of this test is to evaluate the ability of the unit to withstand fatigue stresses and
wear caused by side-to-side forces on the structural frame.

23.3 Test Setup

a) The unit base shall be restrained from horizontal movement on a test surface. Figure 23
shows one acceptable method of restraining the unit. All four corners of the base shall
be restrained in both directions.
b) If adjustable features are available, all adjustments shall be set at normal use conditions.
c) Place a weight of 159 kg (350 lb.) in the center of the seat. If necessary to keep the
weight in position, the weight may be secured.
d) A cycling device shall be attached to the unit side frame midway between front and rear
of the seat at the height of the seat. Note: Where design of the unit does not permit
attachment at the midpoint as specified above, a bridging device may be used.
e) The cycling device shall be adjusted to apply a “push-pull” action, or alternately may be
applied by pull (or push) force applications on opposite sides of the unit. Once cycle
shall consist of one outward and one inward force application.
f) Apply a force of 444 N (100 lbf.) at an appropriate rate between 10 and 30 cycles per
minute.

23.4 Test Procedures

The device shall be cycled for 50,000 cycles.

23.5 Acceptance Level

There shall be no loss of serviceability.

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Appendix A

Impact Test Bag Construction

Example: 406 mm (16 in.) diameter bag

Section A-A

Height approx. 406

mm (16 in.)
A A

Bag diameter =
406 ± 13 mm (16 ± 0.5 in.)

Bag to contain a sufficient quantity of media to bring the bag to the specified load. Media may
be shot, slugs, punches, etc. Media may be contained within smaller individual
bags/compartments. Media may not be a singular solid material (e.g. single steel or concrete
mass).
Note: For health and environmental reasons, lead shot is not recommended. Other fixtures or
media are acceptable if they provide an equivalent impact.

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Appendix A continued
Impact Test Bag – Typical Construction

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Impact Test Bag - Typical Construction

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 ANSI/BIFMA X5.11-2015

Impact Test Bag - Typical Construction

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 ANSI/BIFMA X5.11-2015

Impact Test Bag - Typical Construction

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 ANSI/BIFMA X5.11-2015

Test Bag Handling Suggestions:

Support fixtures for lifting and attaching the bag to test devices may be used to help maintain
the shape of the bag and provide improved consistency, depending on the media chosen.
Examples of support fixtures are shown below:

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Appendix A continued

Note: Other designs may be used to help maintain the shape of the bag and provide improved
consistency.

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Appendix B
Stability Disk - Specification

The disks shall weigh 10 kg ± 0.05 kg (22 lb. ± 0.11 lb.) each, having a diameter of 350 mm
(13.8 in.) and a thickness of 48 mm (1.9 in.). The center of gravity shall be in the center of the
disk. The surface friction of the disk (disk to disk) shall be such that the force to overcome static
friction shall be 31 N ± 9 N (7 lbf ± 2 lbf.).

One acceptable construction of the disk is a sandwich construction consisting of two medium
density fiberboard (mdf) outer plates with steel plates sandwiched in between them. The steel
plates have through holes drilled out for the screws and additional holes symmetrically drilled to
achieve the total weight required. The entire construction is held together with counter-sink
screws into threaded inserts.

One acceptable construction of the disk

End of Document

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