• Luxury glass concrete office interior with city view, daylight, wooden floor furniture and equipment. 3D Rendering
  • Old dirty office ergonomic chair with mesh coating.
  • Modern gadgets in interior of coworking office during COVID-19 epidemic. Chairs and desk for support workers, laptops and headphones, cups and stationery in daylight on window background, free space

New dimensional requirements for office chairs

Ensuring the conformity of office chairs produced and marketed is a fundamental prerequisite to ensure working conditions suitable for the protection and safety of end users.
To this end, the design of the same office workplaces must take into account ergonomic principles and minimum performance and safety requirements.

The dimensional requirements of the seats are defined and described in the standard UNI EN 1335-1:2020 – Office furniture – Office work chair – Part 1: Dimensions – Determination of the dimensions, the latest version of which entered into force in September 2020, introduced some important changes.

The first innovation introduced by the standard concerns the method of determining the measurements for which it is necessary to take as reference the ISO 24496:2017 standard, adopted in the international context; this standard also takes into account the thrust on the backrest, simulating the weight of a seated person leaning on it.
A fundamental aspect to reconcile safety and comfort of the end user.

A further change compared to the previous version of 2000 concerns the introduction of a new type of chair (type AX) for a total of four types of seats (AX, A, B and C).
The AX type seat can cover (compared to other types) a wider range of population, providing greater possibilities of adjustment in terms of depth and height of the seat and maximum distance from the backrest to the front edge of the armrests.

Inside the new version have been inserted four Appendices.
Appendix A includes an explanation of the importance of the different seating settings, Appendix B gives an example of how to interpret the table of dimensional requirements; in Appendix C the dimensions of the neck restraint and head restraint are indicated; Finally, Appendix D contains the measurement uncertainty.

In addition, UNI EN 1335-1:2020 becoming in effect a standard transposed at national level, is used together with UNI EN 1335-2:2018 as a reference standard for the determination of compliance with D.Lgs. 81/2008, on the protection of health and safety at work.

The COSMOB Quality Testing Laboratory, through the execution of physical-mechanical tests, is able to support you in verifying the compliance of office chairs with UNI EN 1335-1:2020.


For further information:

Eng. Luca Tomassini
Mechanical Department Manager – Quality Test Laboratory
l.tomassini@cosmob.it