ATEX Hazardous Area Classification and Explosion Protection Documents
The EC has passed two directives that relate to the prevention of explosions due to the presence of explosive atmospheres (atmosphères explosibles, or ATEX) in industrial facilities. These are known as the ATEX Directives.
The first Directive 94/9/EC requires Member States to take all appropriate measures to ensure that equipment and protective systems intended for use in potentially explosive atmospheres may be placed on the market and put into service only if, when properly installed and maintained and used for their intended purpose, they do not endanger the health and safety of persons and, where appropriate, domestic animals or property.
The second Directive 1999/92/EC requires employers to take technical and/or organisational measures to: prevent the formation of explosive atmospheres or, where the nature of the activity does not allow that, avoid the ignition of explosive atmospheres and mitigate the detrimental effects of an explosion so as to ensure the health and safety of workers. These measures must, where necessary, be combined and/or supplemented with measures against the propagation of explosions. The measures must be reviewed regularly and, in any event, whenever significant changes occur.
Arup provides the following services to assist clients meet the obligations imposed on them by the ATEX Directive:
- Hazardous area classification for explosive gases and vapours, and for combustible dusts:
- identification of flammable materials
- identification and classification of leak sources
- determination of class and extent of hazardous zones
- preparation of report and drawings
- Preparation of Explosion Protection Document
- Survey of electrical and mechanical equipment to determine suitability for area
- Identification of possible sources of static electricity and means of prevention of generation and accumulation
In carrying out a risk assessment, as required by Directive 89/391/EEC the employer shall assess the specific risks arising from explosive atmospheres, including:
- the likelihood that explosive atmospheres will occur and their persistence
- the likelihood that ignition sources, including electrostatic discharges, will be present and become active and effective
- the installations, substances used, processes, and their possible interactions,
- the scale of the anticipated effects.
