Local Exhaust Ventilation (LEV) Testing

Does my business need LEV testing?

Lots of work processes create dust and fumes, for example cutting, drilling, demolition, milling and grinding can create dust. Tiny particles in the air can be inhaled, ingested or cause irritation when they come into contact with the skin or eyes. Ventilation systems, also called extraction or fume control, are designed to circulate fresh air throughout a building. They can comprise a number of different forms of equipment, often creating a complex network of ducting.

LEV systems require regular inspection to ensure they are performing to their design specification and to assess if they need cleaning. Poorly maintained ventilation systems reduce the flow of air through the building. If unmanaged, this can lead to conditions such as asthma, lung scarring and even cancer. Because of this risk to human health, monitoring and inspection is vital. It can establish what remedial work needs to be undertaken to improve system performance and ensure a healthy building.

Approved Code of Practice (ACoP) 33 states that LEV systems should be regularly cleaned, tested and maintained.  This is also required under COSHH statutory law.

Local Exhaust Ventilation (LEV) Testing
Annual inspection, monitoring and testing

The Building and Engineering Services Association (BESA) recommends that you inspect, monitor and test your ventilation system at least annually. However, frequency can vary depending on the quality of the air supply, the level of filtration, and the sensitivity of the serviced area.

At Rock Compliance, our engineers carry out the two surface contaminant monitoring methods recommended by BESA:

  • Deposit Thickness Test (DTT)
  • Vacuum Test (VT)

The DTT measures the pre-clean thickness of the contaminants on the surface of the ductwork.  The VT weighs post-clean contaminants taken from the system. Samples must be taken at various locations in the ductwork to establish a mean reading.  It is important to engage a specialist contractor like Rock Compliance with the skills, training and equipment to gain safe access to the ductwork and take the required readings.

An end-to-end service

Rock Compliance works with you to establish a suitable monitoring regime that guarantees the quality of air flow in your building. We can also advise you on the next appropriate course of action if your ventilation system requires cleaning or remedial attention.

Another key point to note is that we can assist with any mechanical modifications to improve air handling efficiency as a result of our findings and recommendations.

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Whether it is an issue of compliance, an investment decision or you are just not quite sure whether your existing provider is giving you what you want, please contact us. We will be happy to give you advice on how to create low risk, compliant air hygiene systems, ensuring spend is minimised and predictable.

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