Why LEV Testing Isn't Something You Can Afford to Skip

If you run a workshop, factory, laboratory, or any site where dust, fumes, or vapours are part of daily operations, you've probably come across the term "LEV testing" at some point. Maybe your insurance provider asked about it. Maybe HSE mentioned it during an inspection. Either way, it's not just another box-ticking exercise — it's a legal requirement that protects the people breathing that air every single day.

At Ventxlabs Ltd, we get asked about LEV testing constantly, usually by business owners who inherited a ventilation system from a previous tenant and have no idea whether it's actually doing its job. So let's break down what LEV testing actually involves, why it matters, and how often you need it.

What Is LEV Testing?

LEV stands for Local Exhaust Ventilation. In plain terms, it's the equipment designed to capture dust, mist, gas, or fume right at the point where it's created — before it spreads into the air your staff breathe. Think extraction arms above welding stations, hoods over spray booths, or ducted systems pulling wood dust away from a saw.

LEV testing is the formal examination of that equipment to check it's still working the way it was designed to. Under the Control of Substances Hazardous to Health Regulations (COSHH), any business using LEV to control exposure to hazardous substances must have it thoroughly examined and tested at least once every 14 months. Some higher-risk processes need testing more frequently — sometimes every 6 or 12 months, depending on what's being extracted.

The test itself, sometimes called a "TExT" (Thorough Examination and Test), measures things like airflow velocity, capture efficiency, and static pressure at various points in the system. A qualified tester will also inspect the physical condition of hoods, ducting, filters, and fans, then produce a report confirming whether the system is performing within its design specification.

Why It Matters Beyond Compliance

It's easy to see LEV testing as paperwork, but the real purpose is much simpler: keeping people healthy. Long-term exposure to airborne contaminants — wood dust, welding fume, isocyanates, silica, solvent vapours — is linked to conditions like occupational asthma, COPD, and in some cases, cancer. A system that looks fine on the surface can quietly lose effectiveness over months as filters clog, ducting corrodes, or fan belts wear down.

There's also the financial side. HSE inspectors can and do ask to see LEV test certificates, and businesses without valid records face enforcement notices or fines. If an employee later develops a work-related respiratory illness, an out-of-date or missing LEV test can leave a company seriously exposed in any subsequent claim or investigation.

LEV Systems, Explained Separately

Since LEV testing and LEV systems often get mixed up, it's worth pulling the system itself apart from the test.

An LEV system is the actual physical setup used to remove contaminated air from a workspace. It generally has four core parts:

• The hood or intake point – positioned as close as possible to where the contaminant is generated, whether that's a grinding wheel, a chemical process, or a spray booth.

• Ducting – the pipework that carries the captured air away from the workspace.

• An air-moving device – usually a fan or extraction unit that creates the airflow needed to pull contaminants through the system.

• A filter or discharge point – cleaning the air before it's released, or in some setups, recirculated back into the workspace.

The design of an LEV system depends heavily on the process it's serving. A system built for fine dust extraction looks and performs very differently from one designed for solvent vapours or welding fume. That's why a generic, off-the-shelf extraction unit often falls short — it needs to be specified around the actual hazard, the room layout, and how people work around it.

Ventxlabs designs, installs, and tests LEV systems tailored to the specific risks in your workplace, so the equipment and the compliance testing work together rather than being treated as separate problems.

Getting Your LEV System Tested

If it's been more than 14 months since your last test — or you're not sure it's ever been done — it's worth getting a professional assessment sooner rather than later. Ventxlabs Ltd carries out thorough LEV examinations and testing across a range of industries, backed by clear, HSE-compliant reporting you can keep on file.

Get in touch through ventxlabs.co.uk to book a test or ask about upgrading an underperforming system.

Frequently Asked Questions

How often does LEV testing need to be carried out?

Under COSHH regulations, most LEV systems require testing at least every 14 months, though certain high-risk processes need more frequent checks, sometimes every 6 months.

Who is legally allowed to carry out LEV testing?

Testing should be carried out by a competent person with the right training and equipment to assess airflow, capture efficiency, and system condition accurately.

What happens if my LEV system fails a test?

The tester will flag the faults in the report, and the business is expected to repair or upgrade the system before it's used again for the hazardous process.

Is LEV testing a legal requirement?

Yes. Under COSHH, any employer using LEV to control exposure to hazardous substances must have it thoroughly examined and tested regularly.

How long does an LEV test usually take?

It depends on the size and complexity of the system, but most single-system tests take a few hours, while larger multi-point setups can take a full day.