Statutory Requirements for LEV
(Dust/Fume Extraction Plant)

Our assessment

relating to your local exhaust ventilation (LEV) systems will fulfil the requirements of:

The Control of Substances Hazardous to Health (COSHH) Regulations, 2002 (as amended). HSE Guidance Note HS (G) 258 Controlling airborne contaminants at work – A guide to local exhaust ventilation (LEV);

The Thorough examination and testing of the LEV systems will involve the following 3 steps;

  1. A thorough visual examination.
  2. Measurement of technical performance.
  3. Assessment of the LEV systems control effectiveness.
Step 1

The thorough examination (where access permits) will include the inspection of the following;

  • Condition of captor hoods ductwork.
  • Fans/Air movers.
  • Filter/Air cleaning equipment including monitors and alarms.
  • Step 2: The measurement of technical performance will include the following;
  • Static pressure.
  • Duct transport velocity.
  • Temperature
  • Face and/or capture velocities.
  • Pressure drop across fans/filters.

These measurements will be undertaken, where appropriate, using calibrated equipment including various anemometers, manometers, pilot static tubes, etc…

Step 3

The assessment of control effectiveness will include the following;

  • Visual observation of processes and contaminant sources.
  • Effectiveness of LEV at controlling operators exposure.
  • Smoke testing to visualise air movement and contaminant capture.
  • Dust lamp tests, where appropriate.
  • Observations of operator’s interaction with the LEV system.


A detailed examination and test report will follow a HSE approved format and will include measurement test data, schematic diagrams of the LEV systems, an assessment on the control effectiveness of the system and any recommendations for remedial requirements detailed in a prioritised action plan.