ATEX DIRECTIVE
What Is ATEX Directive 94/9/EC?
The ATEX Directive 94/9/EC is a directive adopted by the European Union (EU) to facilitate free trade in the EU by aligning the technical and legal requirements in the member states for products intended for use in potentially explosive atmospheres. CENELEC design standards are still used. All products placed on the market or put into service in the EU for use in potentially explosive atmospheres must comply with the ATEX directive.
Products Covered by the ATEX Directive
This directive covers "Equipment" and "Protective Systems" which may be used in potentially explosive atmospheres created by the presence of flammable gases vapors, mists or dust. "Equipment" is any item which contains or constitutes a potential ignition source and which requires special measures to be incorporated in its design and/or its installation in order to prevent the ignition source from initiating an explosion in the surrounding atmospheres. Also included in the term "equipment" are safety or control devices installed outside of the hazardous area but having an explosion protection function. A wide range of products comes within the definition of equipment, including electric motors, compressors, diesel engines, lighting fittings, control and communication devices and monitoring and detection equipment. "Protective Systems" are items which prevent an explosion that has been initiated from spreading or causing damage. They included flame arrestors, quenching systems, pressure relief panels and fast-acting shut-off valves.
The directive excludes the following types of products:
·
Medical devices
·
Products for use in the presence of explosives
·
Products for domestic use
·
Personal protective equipment
Sea-going vessels and mobile off-shore units
·
Means of transport, except vehicles for use in potentially explosive atmospheres
·
Military equipment
·
New Product Classification Equipment Groups and Categories
The ATEX Directive, in Annex I, defines two Equipment Groups which are subdivided into five Equipment Categories.
Note:
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 Equipment Group and Equipment Category the product belongs.
Equipment Groups and Categories:
Equipment Group I
·
Equipment Category M1
·
Equipment Category M2
·
Equipment Group II
Equipment Category 1
Equipment Category 2
·
Equipment Category 3
·
What Are Equipment Groups?
The two Equipment Groups defined in Annex I are based mining and non-mining applications.
·
Equipment Group I - comprises of equipment intended for use in the underground parts of mines, and to those parts of surface installation of such mines, likely to become endangered by fire damp and/or combustible dust.
·
Equipment Group II - comprises of equipment intended for use in other places likely to become endangered by explosive atmospheres.
·
What Are Equipment Categories?
The Equipment Categories Defined in Annex I 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.
The five Equipment Categories are:
·
Category M1 & M2 for mining applications.
·
Category 1, 2, & 3 for non-mining applications.
·
Equipment Category M1:
Category M1 comprises of equipment which is:
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 means 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:
Category M2 comprises of equipment which is:
· 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
·
Equipment Category 1:
Category 1 comprises of equipment which is:
· 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 means of protection, at least an independent second means 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:
Category 2 comprises of equipment which is:
· 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:
Category 3 comprises of equipment which is:
·
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
