ATEX Directive

 Who Needs to Comply with the ATEX Directive?

Manufacturers of mechanical and electrical equipment, as well as protective systems, intended for safe operation in and around potentially explosive atmospheres and who wish to place their products on the market within the European Union need to comply with the ATEX Directive. 

ATEX Directive Scope

The 'Directive on Equipment and Protective Systems Intended for use in Potentially Explosive Atmospheres' (94/9/EC) entered into force on 1 March 1996.  The Directive is commonly referred to as the 'ATEX' Directive ('ATmospheres EXplosibles'), but may also be called the ATEX Equipment Directive or ATEX 95.

The Directive applies to electrical and/or mechanical equipment used on the surface, below the ground and on fixed offshore installations. Specifically, the Directive covers:

• All equipment intended for use in potentially explosive atmospheres and which are capable of causing an explosion through their own potential sources of ignition.
• Protective systems intended for use in potentially explosive atmospheres. Protective systems are defined as units which are intended to halt incipient explosions immediately and/or to limit the effective range of explosion flames and explosion pressures
• Components, which are defined as any item essential to the safe functioning of equipment and protective systems but with no autonomous function.

ATEX Groups and Categories

Equipment and Products that fall within the scope of the Directive are divided into two Groups: 

• Group I comprises equipment intended for use in mines, above and below ground.
• Group II comprise equipment intended for use in other locations endangered by explosive atmospheres.

Equipment and Products in each Group are divided into Categories based on the level of protection required. The categories are as follows:

Group I
Category M1 - Equipment in this category is required to remain functional with an explosive atmosphere present.
Category M2 - This equipment is intended to be de-energised in the event of an explosive atmosphere forming.

Group II
Category 1 - Equipment in this category is intended for use in areas in which explosive atmospheres caused by mixtures of air and gases, vapors or mists or by air/dust mixtures are present continuously, for long periods or frequently.
Category 2 - Equipment in this category is intended for use in areas in which explosive atmospheres caused by gases, vapors, mists or air/dust mixtures are likely to occur.
Category 3 - Equipment in this category is intended for use in areas in which explosive atmospheres caused by gases, vapors, mists or air/dust mixtures are unlikely to occur or, if they do occur, are likely to do so only infrequently and for a short period only. 

ATEX Zones

In addition to the ATEX Directive 94/9/EC, which covers the safety requirements for equipment to be used in potentially explosive atmospheres, there is an additional European ATEX Directive, 99/92/EC.  This is also known as the 'ATEX Workplace Directive' or 'ATEX 137' and highlights what employers must do to minimise the risk to workers from explosive atmospheres.

ATEX 137 also classifies hazardous areas where an explosive atmosphere could form, by type of hazard, into the following 'Zones'. 

Hazard - Gas, Mists or Vapors

Zone 0 - A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapor 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, vapor 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, vapor or mist is not likely to occur in normal operation but, if it does occur, will persist for a short period only.

Hazard - Dusts

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 or 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.

It is a requirement of ATEX 137 that only certain categories of Group II ATEX certified equipment are used in specific Zones. This requirement can help guide manufacturers on what Category of ATEX certification their product(s) need to achieve.  The Zones and their applicable equipment Categories are as follows:

Zones 0 & 20	Category 1 Equipment only
Zones 1 & 21	Category 1 or 2 Equipment
Zones 2 & 22	Category 1,2 or 3, Equipment

Routes to ATEX Compliance

The ATEX Directive stipulates that products within its scope must satisfy the relevant essential health and safety requirements (EHSRs), and there are three methods of compliance. Equipment must be manufactured in conformity with either:

1. European harmonized standards, or
2. National technical standards and specifications, or
3. Essential health and safety requirements

In every case the standards, specifications or EHSRs applied by a manufacturer must be applicable and relevant to a product's intended ATEX Group & Category and the Zone in which it is to be used.

Where a Harmonized Standard is applied it must cover all essential health and safety requirements and must be the latest version.

Conformity Assessment Procedures

Procedures vary depending on the category of equipment and the zones for which the equipment is intended to be used. In general they are as follows:

EC Type Examination - Examination by a Notified Body of compliance documentation and a sample of the product to be certified
Production QA (Quality Assurance) - The manufacturer shall operate a quality system for production, inspection and testing that has been approved and is regularly assessed by a Notified Body
Product Verification - Each separate unit produced shall be individually assessed by a Notified Body
Conformity to Type - The manufacturer shall take all steps necessary to ensure that all units are manufactured in compliance with the Directive and to the same design and quality as the sample type tested. Each unit manufactured will be subjected to testing approved by a Notified Body
Internal Control of Production - The manufacturer shall prepare technical documentation that allows the conformity of a product to be assessed. In some circumstances a copy of this documentation shall be presented to a Notified Body for review.

In all cases it will be necessary for the manufacturer to prepare a full Technical File for the product(s) that demonstrates their conformity with the requirements of the ATEX Directive 94/9/EC. 

Why use Technology International Group?

Ensuring products and systems meet the requirements of the ATEX Directive can be a complex, time consuming and costly process.  By using Technology International to support ATEX compliance efforts manufacturers can draw upon detailed pre-existing technical knowledge and expertise.  Technology International provide guidance technical requirements, appropriate standards and assist with the preparation of compliance documentation, speeding up the ATEX certification process and ensuring that products reach the market quicker.

Technology International's services include:

• Hazardous Location Compliance Reviews - assessment of product designs, determination of the applicable directives, and development of the most cost-effective plan for regulatory compliance.
• Project Management - complete compliance for all types of products and hazardous locations.
• Technical File Preparation - complete preparation of the technical documentation, risk assessment, and conformity evaluation required to meet the directive.
• Safety Training - customized training on European safety requirements as well as design practices on how to effectively eliminate/reduce hazards.

Under European regulations a Notified Body for the ATEX Directive 94/9/EC cannot also provide wider ATEX consultancy services such as design reviews or preparing compliance documentation. In order to provide the most comprehensive range of services possible to clients, Technology International has therefore chosen not to maintain an ATEX Notified Body appointment.

To take advantage of Technology International's ATEX Directive expertise and services or to disucss your requirements in more detail please contact our sales team using either the 'Ask an Engineer' form or the telephone numbers provided.