Many workplace activities generate airborne contaminants that can affect employee health if they are not properly controlled. Whether it's welding fumes, wood dust, chemical vapours or flour dust, these substances can remain suspended in the air and be inhaled by workers throughout the day.
While some contaminants are visible, many are microscopic and can spread far beyond the area where they are produced. Over time, repeated exposure may increase the risk of respiratory illnesses and other occupational health conditions.
One of the most effective ways to control these hazards is through Local Exhaust Ventilation (LEV). By capturing contaminants at their source before they enter the breathing zone, LEV helps improve workplace air quality, protects employees, and supports compliance with the Control of Substances Hazardous to Health (COSHH) Regulations.
Local Exhaust Ventilation (LEV) controls airborne contaminants by capturing hazardous dust, fumes, vapours and mists at or near their source before they spread throughout the workplace. A properly designed, maintained and regularly tested LEV system helps reduce employee exposure, improve workplace air quality and support compliance with COSHH.
Airborne contaminants are substances released into the air during workplace processes that may present a risk to health when inhaled. They can be generated during manufacturing, construction, laboratory work, food production, engineering and many other industrial activities.
Common airborne contaminants include:
The size and type of contaminant determine how long it remains in the air and how deeply it can enter the respiratory system. Fine particles and fumes are particularly concerning because they can travel throughout the workplace and reach the deepest parts of the lungs.
Without effective controls, long-term exposure may contribute to occupational asthma, respiratory irritation, chronic lung disease and other work-related illnesses.
Unlike general ventilation, which simply dilutes contaminated air, Local Exhaust Ventilation removes contaminants before they have an opportunity to spread.
An LEV system works through four key stages.
The first stage is the most important. A capture hood, extraction arm or enclosure is positioned as close as possible to the process generating the contaminant.
By extracting hazardous substances immediately, the system prevents them from entering the employee's breathing zone or circulating throughout the workplace.
Once captured, contaminated air travels through a network of ductwork.
The ductwork must be correctly designed to maintain sufficient airflow and prevent dust or other particles from settling inside the system.
Depending on the type of contaminant, the extracted air may pass through filters or other cleaning devices that remove harmful particles before the air is discharged.
Different applications require different filtration methods, which is why every LEV system should be designed around the specific process it serves.
After filtration, the cleaned air is safely discharged or, where appropriate, recirculated in accordance with current guidance.
When each stage works together effectively, the result is significantly lower employee exposure and improved workplace air quality.
Even the highest-quality extraction equipment cannot perform effectively if it has been poorly designed.
Factors such as hood placement, airflow, duct sizing and filtration all influence how well contaminants are captured and removed. If the capture point is too far from the source or the airflow is insufficient, hazardous substances may escape into the workplace before they can be extracted.
Every workplace is different, which is why LEV systems should be designed specifically for the processes they are controlling.
At DevineAir, we provide LEV Design and Consultancy to help businesses develop extraction systems that effectively control airborne contaminants while supporting compliance with COSHH. Our experienced engineers assess your workplace, identify potential risks and recommend solutions tailored to your operations.
An LEV system needs regular attention to continue providing effective protection. Over time, filters can become clogged, fans may lose efficiency and ductwork can deteriorate, reducing the system's ability to capture contaminants.
Most LEV systems are legally required to undergo a Thorough Examination and Test (TExT) at least every 14 months under COSHH, although some systems require more frequent examinations depending on the application.
Routine maintenance between statutory examinations is equally important. Regular servicing helps identify developing issues before they affect system performance, reducing the risk of unexpected downtime and helping businesses maintain effective exposure control.
DevineAir provides LEV Thorough Examination and Testing as well as LEV Maintenance and Service Contracts, helping businesses keep their extraction systems operating safely and efficiently.
Managing airborne contaminants requires more than installing an extraction system. Businesses need confidence that their LEV continues to perform as intended and remains suitable for the processes being carried out.
DevineAir supports organisations across the UK with a comprehensive range of LEV services, including:
Our experienced engineers work closely with businesses to help improve workplace air quality, reduce employee exposure and support long-term compliance with COSHH.
Explore our full range of LEV services.
Controlling airborne contaminants is essential for protecting employee health and maintaining a safe working environment. A properly designed and maintained LEV system captures hazardous substances before they spread, making it one of the most effective engineering controls available under COSHH.
Whether you're installing a new extraction system or maintaining an existing one, professional support can help ensure your LEV continues to perform effectively.
At DevineAir, we provide expert LEV design, consultancy, Thorough Examination and Testing (TExT), maintenance and specialist ventilation services to help businesses manage airborne contaminants with confidence. Get in touch with our team to discuss your LEV requirements and discover how we can help you create a safer, healthier workplace.
Airborne contaminants are hazardous substances such as dust, fumes, vapours, mists and aerosols that become suspended in workplace air during industrial or manufacturing processes.
LEV captures contaminants as close to their source as possible, transports them through ductwork, filters the contaminated air where required and safely discharges it, preventing hazardous substances from spreading throughout the workplace.
Where Local Exhaust Ventilation is needed to adequately control exposure to hazardous substances, employers must ensure it is suitable, properly maintained and thoroughly examined in accordance with COSHH requirements.
Most LEV systems require a Thorough Examination and Test (TExT) at least every 14 months, although some applications may require more frequent examinations depending on the process and associated risks.
Dust exposure is a common problem affecting workers in various industries, including construction, manufacturing, woodworking, and the pharmaceutical industry. Without effective management of dust exposure, workers would face health risks detrimental to the company. For this reason, it is important to understand LEV and dust monitoring. Despite their common pairing, each has its own purpose. […]
Construction sites generate a variety of airborne hazards, including silica dust, welding fumes, wood dust, and chemical vapours. If these contaminants are not properly controlled, they can pose serious risks to workers' health and lead to long-term respiratory conditions. This is why LEV testing for construction sites is an important part of workplace safety and […]
Optimized by Seraphinite Accelerator