Local Exhaust Ventilation (LEV) Testing

LEV Testing

LEV Testing FAQs

Local Exhaust Ventilation (LEV) Testing

LEV (local exhaust ventilation) draws pollutants away from a process or operation that is likely to release a hazardous substance into the workroom air. This uses extract ventilation to prevent or reduce the level of airborne hazardous substances from being breathed by people in the workplace.

Under the COSHH (Control of Substances Hazardous to Health) Regulations, Reg 9 covers the use of the LEV system. Regulation 7 requires that

"Every employer shall prevent or, where this is not reasonably practicable adequately control exposure of their employees to substances hazardous to health"

Where the regulation is met through the use of engineering controls, the employer shall ensure that thorough examination and testing of those controls are carried out. In the case of local exhaust ventilation plant, this will be at least every 14 months.

According to HSE figures there are around 100, 000 businesses in the UKthat use LEV systems to control airborne hazards.

Q1. What is an LEV test and why do I need one?

A. In a nutshell, it is a health and safety assessment of Local Exhaust Ventilation components to ensure dust, fume and vapour aren’t escaping and poisoning or harming staff and employees, operators or anyone in the vicinity. You may also hear it referred to as a LEV TExT (Thorough Examination and Test) or a CoSHH report or test. CoSHH stands for Control of Substances Hazardous to Health and it is stated under the Control of Substances Hazardous to Health Regulations 2002 that employers need to either prevent or reduce their workers’ exposure to substances that are hazardous to their health.

Q2. Is there anything I need to do in order to prepare the system for an LEV test?

A. You should have any previous paper work ready like the log book. You should also have some basic details to hand like when the LEV equipment was installed, what it was intended for, if anything has been changed in the system and if any problems have been noted by the operators or people working around the system like dust, fumes, mist or gas seeping from ducting. Employees and operators should really be aware of what they need to look for in a system that is failing as this can cause real harm to people’s health.

Q3. What will happen during an LEV test?

A. Both a quantitative and qualitative test will be conducted. This means the airflow and pressure will be measured using a manometer and other tools for the quantity part of the test. Observations will then be made on hoods, belts, bearing and fans, filter pressure, airflow, leaks around the system, filters and wear and tear on flexes and ducting, which ticks off the quality part of the examination.

Q4. Should I have airflow indicators fitted to all hoods in the LEV system?

A. It’s not a legal requirement to have an airflow indicator fitted but I would highly recommend you fit one as it will help you instantly see if there is a problem with the system’s pressure at a glance (We’ve got a whole other blog post about airflow indicators here which is really useful.) If the airflow is failing, it means the LEV assessment will fail the test. It’s therefore a really quick way to check everything is working as it should be so no one working near that LEV is having their health put at risk. We advise all new installs are fitted with airflow indicators as standard, it just makes life a whole lot easier!

Q5. Can tell-tale signs, such as pieces of paper hanging in the LEV hoods indicate if airflow is working or not?

A. Sadly not. It may look like a good idea but it won’t be accurate and could lull you into a false sense of security. It is best to get your LEV system checked, if in doubt before the recommended 14 month guideline. We offer site inspections which are not full LEV assessments so won’t take as much time but will give you piece of mind on whether hoods, flexes and ducting have adequate airflow operating.

I’ve found all sorts of items clogging up vents and ducts. Some of the weirdest items have been latex gloves, plastic cups, crisp packets and even tin cans. Some people want to test the systems but it just clogs them up and makes them fail. So just watch what you’re eating near to any extraction points or you may go hungry!

Q6. I can’t remember which hoods passed and failed. How will I know?

A. If a hood has been tested, it should have a label on it as a record with the test date, the next test date and the examiner. Examiners aren’t legally bound to do this but I do it as it helps the customer keep track of when the next test is due and it’s great for the employer to quickly see what LEV systems are due for testing. Another quick way to check is by looking at your LEV report.

If a hood fails, a red sticker should be made visible on a hood or system to warn operators and managers. Again, not everyone does this but I like to so that a customer knows it would be dangerous to operate this system. It also means that the issue gets solved more quickly. I clearly tell my customers why a system or hood has failed and what the steps are to pass it so that it can be done right away.

I also put a smoke capture label on hoods so that operators know the minimum measurement the hood can be from the source in order for it to be effective. It’s just a little thing but it keeps staff on the ball and more aware of their working environment.

Q7. Who should conduct my LEV assessment?

A. An LEV test can be conducted by someone who is competent. This means they have the knowledge and experience within the industry to confidently carry out an LEV test. Some LEV engineers like myself, have a P601 accreditation. Go with someone you trust and have had recommendations about and has been doing the work for a couple of years. In my eyes, experience counts for a lot and the qualification is a real bonus.

Q8. Whose responsibility is it ensure LEV systems are tested regularly?

A. It is the legal responsibility of the business owner or manager. Sometimes this falls on the H&S department to organise but the business owner will be penalised if the LEV system goes beyond the 14 month threshold. The LEV service provider’s responsibility is to ensure the system installed is running safely. We send out a reminder a month before the LEV test is due so you don’t have to try and remember.

Q9. Can I dispute an LEV system failure?

A. I wouldn’t waste your time. If it’s a fail, it’s a fail, the numbers don’t lie. An LEV engineer should always talk you through why a system has failed and any recommendations and advice. I would never leave someone in the dark about why they’ve failed and what can be done to turn it to a pass and I hope no decent engineer would. Sometimes I can do some deep cleaning or hood movements there and then to turn something into a pass but other times if it’s a bigger job I’ll get it booked in for the nearest date possible.

Q10. I’ve had my LEV test and passed and I’ve got my next one booked in. Do I need to do anything else?

A. Not really, just ensure your log book is kept up to date and is filed away safely. You will need the CoSHH reports if anything ever goes wrong and legally they need to be kept for up to 5 years after the pass date. Try and keep component parts clean until the next test. By maintaining a system, based on recommendations it might mean the difference between a pass and a fail. Another point to remember is if you change your LEV system in any way it needs to be recommissioned and re-tested to ensure it is safe to run still. People can easily get caught out by this, don’t let yourself be one of them.