Local Exhaust Ventilation (LEV) Testing
Thousands of workers each year contract occupational diseases through breathing in dust, fumes or other airborne contaminants in the workplace. Many of these people die or become permanently disabled and unable to work as a result of these conditions. Local exhaust ventilation, often called dust and/or fume extraction is installed to capture harmful emissions at source and reduce the amount in the workers breathing zone. For these systems to work effectively, they must be well designed and maintained.
Some common types of LEV equipment includes:
- Woodworking machinery dust extraction systems
- Paint spraying booths
- Fume extraction from welding, soldering, brazing or furnaces
- Dust extraction from handling of powders and granular solids
- Mist and dust extraction from metal working machinery
- Dust extraction from stone cutting and grinding
In Britain, the COSHH Regulations are designed to protect workers from exposure to hazardous substances and they introduce a variety of controls aimed at reducing employee exposure. One of these controls relates to LEV testing.
What is Local Exhaust Ventilation?
LEV is an engineering control system that generally incorporates some form of extraction and is designed to capture emissions of airborne contaminants such as dust, fume, vapour or mists in a workplace.
Regulation 9 of COSHH says where LEV is used to control exposure to hazardous substances it must be well maintained and in an efficient state to ensure adequate capture and removal. Regular checks should be carried out by the user but a thorough examination and test must be carried out at least every 14 months. In some cases, where particularly hazardous substances are emitted, testing must be more frequent. Records of examinations, tests and repairs should be made and retained for at least 5 years.