Introduction

The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) requires employers to assess the risks of fires and explosions that may be caused by dangerous substances in the workplace. These risks must then be eliminated or reduced as far as is reasonably practicable. Refer to HSE Guidance DSEAR in detail.

Typical work activities to which this may apply include:

• use of flammable solvents in laboratories

• transporting flammable substances in containers around a workplace

• use of flammable gases, such as acetylene, for welding

• handling and storage of flammable wastes such as fuel oils

• handling, storage and use of gases under pressure

• handling, storage and use of substances corrosive to metal

Dangerous substances are substances or mixtures of substances (called 'preparations' in DSEAR) that could create risks to people's safety from fires and explosions or similar events, such as 'thermal runaway' from chemical reactions, or which are corrosive to metal. Liquids, gases, vapours and dusts that may be found in a workplace can all be dangerous substances. Examples include:

• solvents, such as acetone, toluene, diethyl ether

• paints and varnishes

• flammable gases such as acetylene, hydrogen, propane

• liquefied petroleum gas (LPG)

• dusts from machining and sanding operations

An explosive atmosphere is a mixture of a dangerous substance or substances (gas, mist, dust or vapour) with the air, which has the potential to catch fire or explode.

In addition to fire and explosion events, DSEAR also applies to other energetic events such as runaway exothermic reactions or decompositions of unstable substances, e.g. decomposition of peroxides.

Process for controlling fire and explosion risks

Refer to HSE Documents for guidance:

Dangerous Substances and Explosive Atmospheres Regulations 2002

Approved Code of Practice and guidance L138

HSE Guidance Controlling Fire and Explosion risk in the workplace

The Code of Practice Dangerous Substances and Explosives Atmospheres sets out the University's arrangements for managing fire and explosion risk in University buildings. The CoP sets out the methodology to be used to identify, assess and control risks as required by the DSEAR Regulations. The CoP also provides more information on the roles of responsibilities of line managers, supervisors, employees and students working with in scope materials.