The risks

Risks associated with operation of diesel engines in areas in which flammable gases or vapours may enter the atmosphere or where other readily combustable materials may exist.

When diesel engines operate in locations where petrochemical or other flammable gas or vapours may be present, even if normally contained, it is now accepted health and safety practice to fit diesel engine air intake shut down valves and exhaust spark arrestors as standard.

In the event of a run away engine, or where normal engine fuel shut down fails to stop the the engine due to the ingestion of flammables from the atmosphere acting as an additional fuel input, the closure of the the air intake valve ensures immediate engine shut down thereby substantially reducing the potential for a serious incident due to mechanical failure and / or the ignition of the surrounding atmosphere.

Where the hazard comprises combustible solids, possibly in the form of dust, as may exist for example in agriculture or forestry environments, an exhaust spark arrestor is a well proven means of restricting the emission of high energy sparks which have the potential of igniting such combustible materials.