Two European Union directives, 94/9/EC – principally for manufacturers, and 1999/92/EC – for operators of plant, have given rise to the many harmonised standards to enable this law to be implemented.

In the UK, the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) implement the directive 1999/92/EC.

Directive 94/9/EC is implemented in the UK by the Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations 1996 (EPS Regulations).

Whilst both these EU directives have been in existence for some years, 94/9/EC became legally enforceable on July 1st 2003 and the transitional provisions of 1999/92/EC extended to 1st July 2006.

Most previous legislation regulating explosive atmospheres has been aimed at electrical equipment. The ATEX directives also include hazards from mechanical sources and therefore the equipment scrutinized and regulated will be diverse.

It is the owner/operators responsibility to determine the risk of possible explosion in his premises and a risk assessment must be carried out to allow him to declare his zones under ATEX directive 1999/92/EC, to comply with DSEAR regulations.

It will then be possible for the manufacturer or supplier of equipment to be able to assess the ATEX category required for such machinery and equipment.

A supplier of machinery or equipment for handling or for use within explosive dusty atmospheres will need data from the customer who will be the employer and operator of such machinery.

  • The properties of the material to be handled, including its explosion class – St1, St2 or St3. For St3 rated materials, the actual explosibility – kSt should be known in order to determine the nature and capacity of necessary protective devices for ATEX compliance.
  • The ATEX zone classification of the areas into which the machinery will be installed will be required and this is the responsibility of the owner/employer/operator.
  • The operator is responsible for the safety of the machinery and equipment under DSEAR regulations, so it is his responsibility to produce risk assessments and keep operation and maintenance records. Information and declarations from his suppliers of machinery and equipment may be used to support this dossier, but the final responsibility nonetheless remains with the operator.
For more details follow the link to the pdf guidance notes compiled by SHAPA – ‘Practical Guidance for Suppliers and Operators of Solids Handling Equipment for Potentially Explosive Dusts’ or follow the link to the HSE website – http://www.hse.gov.uk/fireandexplosion/atex.htm