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
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