Written by CMSE Safety Consultant Jake Bumpus

ATEX is short for the French phrase “Atmosphères Explosibles”, and refers to two EU Directives which set out legal requirements relating to potentially explosive atmospheres:

  • Directive 2014/34/EU (or the “Equipment Directive”) – which sets out requirements for equipment for use in potentially explosive atmospheres.
  • Directive 99/92/EC (or the “Workplace Directive”) – which sets out requirements for managing the risks of potentially explosive atmospheres which may be present in workplaces.

It is primarily the Workplace Directive which would be relevant to the operations of a pharmaceutical facility. It is likely that the facility handles materials such as flammable solvents (e.g. ethanol, IPA, hexane) and fine organic powders (e.g. cellulose), which due to their inherent material properties, have the potential to form an explosive atmosphere on site. If not managed correctly, there is a risk that handling of these materials could lead to an explosion, which could cause severe consequences for those present on site, the plant and equipment, and even for those off-site.

In Ireland, the ATEX Workplace Directive is implemented by Part 8 (Explosive Atmospheres at Places of Work) of the Safety, Health and Welfare at Work (General Application) Regulations 2007. Under these regulations, those in control of a workplace where an explosive atmosphere could form have a number of legal responsibilities. These include:

  • A risk assessment must be carried out for any work activities that involve flammable substances.
  • The findings of these explosion risk assessments must be recorded in a document (referred to as an “Explosion Protection Document”, or EPD), which must be available to employees.
  • Places where explosive atmospheres may occur must be classified into zones.

The requirement to classify places where explosive atmospheres may occur is also known as “Hazardous Area Classification”. Hazardous areas can be classified into zones based upon the expected frequency of the occurrence and duration of an explosive atmosphere, as follows:

  • Zone 0/20 – “A place in which an explosive atmosphere… is present continuously, or for long periods, or frequently”.
  • Zone 1/21 – “A place in which an explosive atmosphere… is likely to occur in normal operation occasionally”.
  • Zone 2/22 – “A place in which an explosive atmosphere… is not likely to occur in normal operation but, if it does occur, will persist for a short period only”.

All hazardous areas (also known as ATEX Zones) must be clearly indicated by signage, and all equipment within these areas must be suitably Ex-rated for use in that zone.


CMSE Consultancy provides a top quality ATEX consultancy and support service to our clients nationwide. We have extensive ATEX experience and a proven track record in providing these services across many industrial sectors.

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