Local Exhaust Ventilation (LEV) systems are a critical control measure used to protect workers from harmful airborne contaminants such as dust, fumes, vapours and gases. These systems capture contaminants at the source and remove them from the workplace environment, reducing the risk of exposure and protecting employee health. However, installing an LEV system is only the first step. To ensure it continues to operate effectively, it must be regularly inspected, maintained and tested. This article explains what LEV testing is, why it is legally required, and how businesses can remain compliant with UK health and safety regulations.
What is LEV?
Local Exhaust Ventilation (LEV) is a ventilation system designed to extract airborne contaminants directly from the point where they are generated. These contaminants may include dust, fumes, mists, vapours or gases produced during industrial processes.
A typical LEV system consists of several key components:
- Hood or capture device – collects the contaminant at source
- Ducting – transports the contaminated air away from the workplace
- Air cleaner or filter – removes harmful particles from the air
- Fan or air mover – creates airflow through the system
- Exhaust outlet – safely releases cleaned air outside the building
When designed and maintained properly, LEV systems significantly reduce worker exposure to hazardous substances.
Why LEV Testing is Important
LEV systems play a vital role in protecting workers from hazardous substances that can cause serious health problems, including respiratory diseases and occupational illnesses.
Regular testing ensures that the system:
- Continues to capture and remove contaminants effectively
- Meets the performance standards established during commissioning
- Identifies faults, damage or deterioration early
- Protects employees and maintains workplace compliance
Without regular examination, components such as filters, ducting or fans can become blocked or damaged, reducing the effectiveness of the entire system.
Legal Requirements for LEV Testing in the UK
Under the Control of Substances Hazardous to Health Regulations (COSHH), employers must ensure that control measures such as LEV systems are properly maintained and effective.
The HSE states that LEV systems must undergo a thorough examination and test at least every 14 months, although some systems may require more frequent testing depending on their use or operating conditions.
Employers must also:
- Maintain the system in efficient working order
- Keep records of LEV test reports
- Retain these records for at least five years
- Address any faults or defects identified during testing
Failure to comply with these requirements could lead to enforcement action and increased risk to employee health.
What Happens During an LEV Test?
A thorough examination and test of an LEV system normally includes two key stages.
1. Visual Inspection
The examiner will inspect the system components for damage, wear or deterioration. This may include:
- Checking the hood, ductwork and extraction unit
- Inspecting seals, connections and structural condition
- Confirming filters are correctly fitted and functional
- Reviewing airflow indicators and safety controls
2. Performance Testing
Technical measurements are carried out to ensure the system is performing effectively. This may include:
- Measuring airflow or air velocity
- Testing pressure levels within ducting
- Confirming airflow indicators function correctly
- Assessing whether the system still meets required performance standards
The results are documented in a detailed LEV examination report.
The Importance of LEV Commissioning
Before an LEV system is put into operation, it should be commissioned to ensure it effectively controls exposure to hazardous substances. Commissioning establishes the baseline performance data used during future inspections and tests.
A commissioning report typically includes:
- System identification and location
- Test methods and results
- Airflow measurements and performance targets
- Details of system components and configuration
- Any adjustments or repairs made during commissioning
This information helps engineers compare future test results against the system’s original performance.
Responsibilities of Employers
Employers have a legal duty to ensure that LEV systems continue to provide adequate protection for employees.
Key responsibilities include:
- Arranging regular LEV testing by a competent person
- Maintaining the system between inspections
- Ensuring employees are trained in proper LEV use
- Keeping accurate maintenance and test records
- Acting promptly on any faults identified
Regular inspections and maintenance checks throughout the year also help ensure systems remain effective between statutory tests.
Common Industries That Use LEV
LEV systems are commonly used in workplaces where airborne contaminants are generated, including:
- Construction and demolition
- Manufacturing and fabrication
- Welding and metalworking
- Woodworking and joinery
- Chemical processing
- Automotive repair
- Pharmaceutical and laboratory environments
In these environments, effective ventilation systems are essential to protect workers from potentially hazardous airborne substances.
Final Thoughts
Local Exhaust Ventilation systems are a vital part of workplace safety when hazardous airborne substances are present. Regular LEV testing ensures these systems continue to perform effectively and comply with UK safety regulations.
By implementing proper testing, maintenance and training procedures, employers can safeguard their workforce while meeting their legal obligations under COSHH.
Ensuring your LEV system is regularly examined and tested not only protects employees but also demonstrates a proactive commitment to health and safety.
Contact our team today to arrange a professional survey and find out how our LEV Testing can protect you for the long term including our other services such as Fire Damper Testing, Air Ventilation System Cleaning and Laundry Duct Cleaning.