Often we pay little attention to the technical features of office chairs, considering them secondary to the office furniture. In fact, they play a major role, being the object on which you spend most of the day sitting.
Moreover, among the general measures of health and safety of workers in the workplace (Consolidated Safety at Work - Leg. 81/2008 - corrective and related provisions - Leg. 106/2009) also form part of it the respect of ergonomic principles in the organization of work, in the design of workplaces, in the selection of equipment and in the definition of working methods and production, in order to reduce the health effects of the monotonous and repetitive work.
The work in the office is fully part of this category. It becomes, therefore, essential to pay particular attention to the choice of office furniture, but mostly it is essential to know the technical features an office chair must have.
The ergonomic principles and the minimum functional requirements of an office chair are contained in the following standards:
- UNI EN 1335-2, safety requirements;
- UNI EN 1335-3, test methods for safety;
- UNI EN 1335-1, size and sizing.
The UNI EN 1335-2 2009, "Office furniture - Office chair - Part 2: Safety requirements", specifies the requirements for mechanical safety of office chairs. The characteristics are based on a daily usage of 8 hours by a person weighing 110 kg. Appendix A includes the standard loads, masses and cycle safety tests.
The UNI EN 1335-3 2009, "Office furniture - Office chair - Part 3: Test methods" specifies, however, the test methods to verify the stability, strength and durability of the office chairs. The approval tests must be applied to the chair as an article of office furniture, fully assembled and ready for use. The tests consist in applying forces simulating normal functional use and have been developed to evaluate the properties of the work chair, while do not apply to materials, design, production process.
While it remains in force the norm UNI EN 1335-1 Year 2000 "Office furniture - Office chair - Dimensions - Determination of size", which specifies both the size of three types of chairs (A, B and C) and the test methods for the determination of this size.