Devices

The Atex directive classifies devices in different equipment categories that are based on the level of precautions required according to the likelihood of the presence of an explosive atmosphere. Since higher levels of precaution are more expensive to achieve, classification of equipment into categories enables precautions to be taken that are appropriate to the risk.

Group 1 (For mining applications)

Equipment Category M1

Intended for use in mines endangered by fire damp and/or coal dust.Required to remain functional, even in the event of rare incidents relating to equipment, with an explosive atmosphere present, and is characterized by the means of protection such that:

Either, in the event of failure of one means of protection, at least an independent second mean provides the requisite level of protection.

Or the requisite level of protection is assured in the event of faults occurring independently of each other.

Equipment Category M2

Intended for use in mines endangered by fire damp and/or coal dust.

Required to be de-energized in the event of an explosive atmosphere.
The means of protection relating to equipment in this category assure the requisite level of protection during normal operation and also in the care of more severe operating conditions, in particular those arising from rough handling and changing environmental conditions.

Note : For Conformity Assessment, Category M2 is sub-divided into:

- Electrical equipment and internal combustion engines.
- Non-electrical equipment.

Group 2 (Non mining applications)

Equipment Category 1

Intended for use in areas which an explosive atmosphere is continuously present or for long periods of time:

• Equipment in this category must ensure the requisite level of protection, even in the event of rare incidents relating to equipment, and is characterized by means of protection such that either, in the event of failure of one mean of protection, at least an independent second mean provides the requisite level of protection.
Or the requisite level of protection is assured in the event of two faults occurring independently of each other.

Equipment Category 2

Intended for use in areas which an explosive atmosphere is likely to occur.

• The means of protection relating to equipment in this category ensure the requisite level of protection, even in the event of frequent occurring disturbances or equipment faults which normally have to be taken into account.

Note : for Conformity Assessment, Category 2 is sub-divided into:

• Electrical equipment and internal combustion engines.

• Non-electrical equipment.

Equipment Category 3

Intended for use in areas which an explosive atmosphere is unlikely to occur or only to occur infrequently or for short period of time.

Equipment in this category ensures the requisite level of protection during normal operation.