LEV Testing

Control of Substances Hazardous to Health

COSHH Regulations provide an indication to what an employer should be aware of regarding the prevention of harm to employees due to hazardous materials within a working environment. REGULATION 7 of these regulations states that;

“Every employer shall ensure that the exposure of his employees to substances hazardous to health is either prevented or, where this is not reasonably practicable, adequately controlled.”

This is supported by the COSHH Approved Code of Practice, which lists ways in which control can be achieved and makes specific mention of enclosure, partial enclosure with LEV, LEV and sufficient general ventilation.

An Introduction to Local Exhaust Ventilation

What is a local Exhaust Ventilation System?

It is a system that:

  • Uses extract ventilation to prevent or reduce the level of airborne hazardous.
  • Substances from being breathed by people in the work place
  • Draws pollutants away from a process or operation that is likely to release a hazardous substance into the workroom air
  • Consists of an inlet such as a hood, slot, booth or cabinet placed around or close to the point of release of the substance.
  • This device is connected via ducting to the inlet of a fan or air mover.
  • The extracted air is usually discharged to the atmosphere or returned elsewhere in the workplace, having first been cleaned to make it safe for release.

A diagram of the components in a typical LEV installation is displayed to the right.

When may LEV be required?

  • Heat Treatment - including: Welding; Forging; Brazing; Casting; and Soldering.
  • Wood Work Machinery - including: Saws; Sanders; Planers & Thicknessers; and CNC.
  • Chemical Processes - including: Acid Pickling; Plastics or Glass Reinforced Plastic; Paint
  • Spraying; and Engine Exhaust Emissions.
  • Working with adhesives or printing processes.
  • Working with ceramics or glazes.

Why Do LEV System require Testing

REGULATION 9 of COSHH requires that any control measure taken to comply with REGULATION 7 must be maintained in an efficient state, in efficient working order and in good repair.

Obviously, over time, an extraction system will deteriorate and become less efficient. Regular testing of a system allows any potential problems to be found, and repaired, before major problems can occur. Due to the various components that make up an LEV system, there are a number of different parts that can fail testing, for a number of different reasons:

  • Static items, such as rigid ducts and hoods, etc should not wear unduly with time. However, they may become mechanically damaged by external materialsand/or worn or corroded by materials carried in the duct.
  • Moving items, such as fan bearings, drives and motors, and filter shakers, wear more quickly. This is because of their comparitively large workload within the system.
  • Components such as flexible ducts and filter fabric naturally deteriorate with use.
  • Some items may need frequent attention, e.g. filter bins and waste containers, both of which need emptying on a daily weekly basis, and cell type filters on paint spray booths, which may need replacement at the end of each working shift.
  • If any component of the ventilation develops a fault, the capabilities of the extraction can become extremely impaired and fail to safely remove all hazardous fumes/dust from the work zone.

How often should LEV Systems be tested

LEV testing by HME

We are accredited through ISO 9001:2008 and UKAS, ensuring that all of our engineers are fully competent and impartial when carrying out this service. For more information about our LEV services, or to book a test, you can contact us by phone at +44 (0)1527 839000, e-mail, or by using our contact form.

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