Local exhaust ventilation (LEV) systems are an important system in many workplaces for employee safety, health and compliance.
In this guide, we will outline the basics of LEV systems, how they work, the key components, key applications and how we can support your business.
What are LEV systems?
Often used alongside extractors in a broader workplace safety package, local exhaust ventilation (LEV) systems help to capture and remove dust, dirt and fumes, gas and vapours from closed environments where your teams work.
By cleaning away dirty air at source, LEVs ensure your operators can’t breathe in substances that might otherwise harm their wellbeing, and ensures your site stays compliant with all relevant health and safety laws.
How does a LEV system work?
An LEV system’s job is to pull dirty air away from a specific area and make sure it can’t enter the workers breathing zone The air is filtered where required before removing it from the building. But as different buildings will have different challenges, the design and selection of each LEV component must be carefully considered carefully.
As part of the planning process, your installer will think about hazards, processes, and the wider workplace environment. This way, you’ll be left with a system that effectively controls exposure and keeps everyone safe.
Where are LEV systems used?
From lab testing to workshops, LEV systems are used to control harmful particles and fumes right across the private and public sector. Example applications include extracting debris from saws and other cutting tools, protecting lab researchers from chemical exposure, and cleaning the air around conveyor or factory production lines.
What are the different parts of an LEV?
Hood
An LEV system’s all-important hood is the first component to ‘capture’ contaminants from the process in question. For this reason, it’s usually placed right next to the source. LEV hoods can take different forms to suit the process involved. This could mean a canopy above where a substance is emitted, or a downdraft that pulls dirty air away.
Ducting
Ductwork has the critical role of carrying contaminants through the LEV system. The whole system’s health depends on there being no blockages along the way; this way, free-flowing air can carry all contaminants out through the pipes.
Filters
Generally speaking, a filter will remove contaminants from passing air, though its actual spec will vary significantly depending on the application or risk profile. As with all safety systems, LEV filters should be cleaned and maintained to help protect the integrity of the whole system.
Fans
An LEV fan generates the flow needed to carry air through the hood and the ductwork. Like filters, fans need to be optimised for the application so that all dirt, gases or vapours are fully removed.
Exhaust
At the end of an LEV’s ductwork is the exhaust fan and stack, which discharges extracted air. This is usually placed well away from the contaminant source and is likely to be on the outside of the building at roof level, our LEV engineers will check the key components of the fan and also the stack to ensure the contaminated air is discharge in a safe position and beyond the builds boundary layer.
Support for your own LEV systems
JLA has a wealth of experience supporting organisations with fume extraction and LEV solutions, as part of our sterile equipment division.
From filter boxes to thorough examination testing (TExT), as well as annual certification to COSHH in line with HSG258 and the re-location of units, our experts can help you keep your workplace safe and compliant.
To speak to an expert today, please get in touch.
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