Diesel Engine Exhaust Emissions (DEEEs)

Control Measures

Occupational exposure to diesel engine exhaust emissions (DEEEs) can occur where diesel fuelled engines operate in the workplace. The potential exposure and the level of risk will be different depending on the type of workplace. For example, there may be increased exposure where fork-lift trucks are being used in a warehouse all day for moving goods, whereas in a maintenance depot the exposure may be intermittent as the vehicles enter, stay there for maintenance, and then leave.

Health and safety legislation requires employers to prevent the exposure of employees and others to substances hazardous to health. Exposure to DEEEs can be prevented by adopting one or a combination of options, for example:

• changing the method of working
• modifying the layout of the workplace
• modifying the operations to eliminate exhaust emissions inside the workplace
• substituting diesel fuel with a safer fuel (low sulphur diesel fuel) or alternative technology where practicable, e.g. compressed natural gas, battery powered vehicles

Where prevention of DEEEs is not reasonably practicable, other control measures should be considered.

Engineering controls may take several forms including the use of lower emission or more fuel-efficient engines. Enclosing the exhaust tailpipe from which DEEEs are emitted, for example by using a fixed flexible hose with a tailpipe exhaust extraction system, is an effective way of removing harmful exhaust emissions. Extraction systems of this nature are referred to as local exhaust ventilation (LEV) systems.

Where LEV is used, employers should ensure that employees are trained on how to operate the equipment and that it has been suitably maintained and thoroughly examined so as to ensure it is performing as intended. Further information on LEV systems is available within HSE guidance entitled Controlling airborne contaminants at work: A guide to local exhaust ventilation (LEV) HSG258.

Other engineering controls may include the use of filters attached to tailpipes or catalytic converters as an ‘after treatment’ system.

Other more general measures are sometimes referred to as administrative controls and may include the following:

• turning off engines when not required
• keeping doors and windows open where practicable
• installing air vents in the walls and ceiling
• job rotation

Respiratory protective equipment should only be used as a last resort when other means of control are not suitable.

Where respiratory protection is needed:

• Workers should ensure they are wearing the right type of respirator for the job.
• Workers must have had a face-fit test to ensure tight-fitting respirators fit properly and be clean shaven for this type of respirator to work effectively.
• Workers should be trained to use, check and clean the respirator.
• The filters or disposable respirators should be changed regularly.
• The equipment should be stored in a clean, dust-free place.
• If any defects are found, or the respirator does not fit, is dirty or its filter is old, it should be replaced.

More detailed information on controlling DEEEs are available within the following HSE publications:

• Control of diesel engine exhaust emissions in the workplace (HSG187)
• Diesel Engine Exhaust Emissions (INDG286)

Specific sector information on controlling DEEEs is available within the following HSE publications:

• Health and safety in motor vehicle repair and associated industries (HSG261)
• Vehicle exhaust fumes (in warehouses, garages etc.) (Service and retail control guidance sheet SR14)
• Exhaust fumes from moving vehicles (SR15 Service and retail control guidance sheet SR15)