§133 機器グループのカテゴリーへの分類

The ATEX Directive 2014/34/EU divides equipment into two groups. In order to determine the appropriate conformity assessment procedure, the manufacturer must first come to a decision based on the intended use, as to which group and category the product belongs.

It should be noted that devices have to follow the conformity assessment procedure according to the category of the equipment or protective system they are required for or contribute to. Devices and components may be suitable for one or more category or group of equipment.

Equipment-group I comprises equipment intended for use in the underground parts of mines, and to those parts of surface installations of such mines, likely to become endangered by firedamp and/or combustible dust.

Equipment-group II comprises equipment intended for use in other places likely to become endangered by explosive atmospheres.

These groups are sub-divided into categories. The way in which this categorisation has been developed highlights one of the main distinctions of equipment-group I and II. For group I, the categorisation depends on (amongst other factors) whether the product is to be de-energised in the event of an explosive atmosphere occurring. For group II, it depends where the product is intended to be used in and whether a potentially explosive atmosphere, is always present, or is likely to occur for a long or a short period of time.

The various categories of equipment must be capable of functioning in conformity with the operational parameters established by the manufacturer to a certain level of protection – see below Table 5: Levels of protection.

Such table makes references to the concept of "zone" as defined in the ATEX "workplace" Directive 1999/92/EC and it is based on the "normal" correspondence according to it. It should be noted that, when the group and category are a defined property of the equipment according to the ATEX "product" Directive 2014/34/EU, the zone is a defined property of the physical location and likelihood of an explosive atmosphere being present. Directive 1999/92/EC provides a "normal" correspondence between the zone and the category of equipment that may be installed in the zone. However, it also provides for varying this relationship according to a detailed risk assessment and also allows for the possibility that, in implementing Directive 1999/92/EC, individual Member States, may have changed the "normal" correspondence for particular situations.

Table 5: Levels of protection (*) See as well the directives on minimum requirements for improving the safety and health protection of workers operating in potentially explosive atmospheres, e.g. those indicated in footnote 7 in the "Introduction". The equipment in the various categories must also comply with the relevant essential and supplementary requirements detailed in Annex II to the Directive (essential health and safety requirements).