HSE Explosive Atmospheres – Area Zoning

Unmarked guide from HSE providing information on Hazardous area classification.

This should be carried out as an integral part of the risk assessment to identify places (or areas) where controls over ignition sources are needed (hazardous places) and also those places where they are not (non hazardous places).

Hazardous places are further classified in Zones which distinguish between places that have a high chance of an explosive atmosphere occurring and those places where an explosive atmosphere may only occur occasionally or in abnormal circumstances.

The definitions of the Zones (which are included in DSEAR) also recognise that the chance of a fire or explosion depends on the likelihood of an explosive atmosphere occurring at the same time as an ignition source becomes active.

Link to Guidance on HSE website: Explosive Atmospheres – Zoning