ATEX Categories and Hazardous Zones 
Background Information The ATEX ‘User’ Directive (1999/92/EC), Implemented under the DSEAR Regulations in the UK, requires employers to identify and classify areas of the workplace where explosive atmospheres may occur. They must then purchase appropriately certified equipment for use in the hazardous zones they have identified. Zones Hazardous areas are sub-divided into zones depending upon the type of flammable mixture and the likelihood of it being present. Equipment Categories The ATEX ‘Equipment’ Directive (94/9/EC) defines three categories of equipment depending on the level of protection provided. Category 1 equipment provides a very high level of protection, Category 2 equipment provides a high level of protection and Category 3 a normal level of protection. Separate categories M1 and M2 apply to mining equipment.
The table below defines the zones and indicates what category ATEX certificate is required for equipment located in those zones. Zone
| ATEX Equipment Category
| Definition of Zone
| Gases & Vapours
| Dusts
| 0
| 20
| 1
| Hazardous atmospheres are present under normal operation and for long periods of time.
| 1
| 21
| 2
| Hazardous atmospheres may be present under normal operation but only for short periods of time.
| 2
| 22
| 3
| Hazardous atmospheres only present under fault conditions and only for very short periods of time.
|
Do I need a Notified Body certificate for my product?
The answer depends on the type of product and the category of equipment as defined in the table below.
Certain categories of equipment require Notified Body involvement in issuing a Type Examination Certificate to cover the design and a Quality Assurance Notification (QAN) covering the ongoing manufacture of the product.
| Responsibility
| Category
| Equip.
| Design
| QAN
| 1
| elec
| N.B
| N.B
| non-elec
| N.B
| N.B
| 2
| elec
| N.B
| N.B
| non-elec
| M
| M
| 3
| elec
| M
| M
| non-elec
| M
| M
|
N.B – Notified Body
M – Manufacturer
A Notified Body is appointed by a member state within the European Union and ‘notified’ to the European Commission as competent to operate the conformity assessment procedures of the ATEX Directive 94/9/EC. |
