Control of Substances Hazardous to Health Regulations (Northern Ireland) 2003

What is LEV?

Local exhaust ventilation is an extract ventilation system that takes airborne contaminants such as dusts, mists, gases, vapour or fumes out of the workplace air so that they can't be breathed in.


Statutory Thorough examination 

Every Local exhaust ventilation system requires a statutory thorough examination at least every 14 months. A thorough examination and test is a detailed and systematic examination to make sure that the  local exhaust ventilation system can continue to perform as intended and will contribute to the adequate control of exposure. The employer should keep a copy of the report for at least five years.

Duties under these Regulations

Where a duty is placed by these Regulations on an employer in respect of his employees, he shall, so far as is reasonably practicable, be under a like duty in respect of any other person, whether at work or not, who may be affected by the work carried out by the employer except that the duties of the employer. 

A designed Local Exhaust System will:


Collect the air that contains the contaminants

Make sure they are contained and taken away from people

Clean the air (if necessary) and get rid of the contaminants safely

If your work produces dust flour dust in bakeries, mist from spraying, fumes from welding, gas carbon monoxide from furnaces or vapour from solvents from painting, there may be a risk to health.