Introduction

0.1 General working condition

The working conditions and the protection of office workers with respect to safety and health necessitates that these standards take ergonomic principles and minimum requirements into account. This applies in particular to the design of Visual Display Equipment (VDU) workstations where EU Directive (90/270/EEC) has been implemented. These workstations should be designed to allow different users to carry out a variety of work tasks.

0.2 Basis of dimensions and chair types

The dimensions in this document are based on anthropometric measurements, mechanical design subjective preference and other factors.

The aim of this document is to provide dimensions for the office work chairs which can accommodate a larger part of the European population. Due to the wide variation in population heights and other body dimensions, there will be a variation of the office population between each country, which the dimensions will accommodate. People with body dimensions outside this range may need furniture of different dimensions or adaptations to existing workstations e.g. a footrest.

In this document , office work chairs are categorized into types of chairs based on dimensional requirements.

Type Ax and Type A chairs have more adjustability with a greater range of adjustments than Type B and Type C chairs.

Annex A (Rationale) of this document gives the rationale for chair dimensions and information regarding the importance of good fit between the user and the chair.

0.3 Design reference seating posture

In order to articulate acceptable requirements for comfort and performance with respect to body dimensions, it is important to specify a design reference posture for purposes of specifying anthropometric data. While empirical evidence has indicated that the posture so specified could be comfortable for users carrying out certain tasks over short periods, it does not represent the optimum posture or the posture to strive for.

The reference seating posture is as follows:

— The sole of the foot is placed on the floor;
— The foot forms an angle of approximately 90° with the lower leg;
— The lower leg is approximately vertical;
— The lower leg forms an angle of approximately 90° with the thigh;
— The thigh is almost horizontal;
— The thigh forms an angle of approximately 90° with the trunk;
— The trunk is erect.

0.4 Seating postures

The purpose of well-designed seating is to provide stable support which allows movement, comfort, and task accomplishment. Together with job content and the design of other furniture elements, seating design plays an important role in encouraging movement. Thus, seat design should allow frequent postural variation by the user in order to avoid muscle stress and circulatory problems.

BS EN 1335-1:2020

Office furniture. Office work chair - Dimensions. Determination of dimensions

Current, Under Review

Published:

31 Aug 2020