ATEX Standards

Atex  standards:

• Atex stands for atmosphere explosives .
• As of july 2003 ,organizations in EU must follow the directives to protect employees from exploision risk in areas with an explosive atmosphere.
• There are two atex  directives (one for the manufacturer and one for user of the equipments.

1.The Atex  95 equipment directive 94/9/EC equipment and protective systems  intended for use in potentially explosive atmospheres.

2.Atex 137 work place directive  99/92/EC ,minimum requirements for improving the safety  and health protection of the workers potentially at risk from explosive atmospheres.

ATEX Coding

EX	European union explosives atmosphere symbol
ii	Equipment group
	1.Mining
	2.Surface
2	Equipment Category:
	M1. Energized
	M2. Deenergized.
	1. Very high protection.
	2. High Protection.
	3.Normal Protection
G	Gas
	0 1 2
D	20
	21
	22

Hazardous area zones and equipment categories Hazardous places are classified in terms of zones on the basis of the frequency and duration of the occurrence of an explosive atmosphere.

Gases, vapours and mists For gases, vapors and mists the zone classifications are:

Zone 0:  A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is present continuously or for long periods or frequently.

Zone 1:  A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally.

Zone 2:  A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is not likely to occur in normal operation but, if it does occur, will persist for a short period only.

Dusts: For dusts the zone classifications are:

Zone 20: A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is present continuously, or for long periods or frequently.

Zone 21:  A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is likely to occur in normal operation occasionally.

Zone 22:  A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is not likely to occur in normal operation but, if it does occur, will persist for a short period only.