scope:

This part of IEC 61241 specifies general requirements, additional to those required for basic electrical safety, for the selection of electrical apparatus and instruments, and associated equipment, and for the installation of the electrical apparatus to ensure safe use in areas where combustible dust may be present in quantities, which could lead to a fire or explosion hazard. The application of electrical apparatus in atmospheres, which may contain explosive gas as well as combustible dust, whether simultaneously or separately, requires additional protective measures, which are not within the scope of this standard. This standard includes several types of protection that protect either from ingress of dust or have insufficient energy to cause ignition and provide surface temperature limitation. The principles of this standard may also be followed when combustible fibres or flyings cause a hazard. Where the apparatus has to meet other environmental conditions, for example, protection against ingress of water and resistance to corrosion, additional methods of protection may be necessary. The method used is not to adversely affect the integrity of the enclosure. The requirements of this standard apply only to the use of electrical apparatus under normal or near normal atmospheric conditions. For other conditions, additional precautions may be necessary. For example, most flammable materials and many materials, which are normally regarded as non-flammable, might burn vigorously under conditions of oxygen enrichment. Other precautions might also be necessar