Local Exhaust Ventilation (LEV) systems are engineering controls designed to capture and remove airborne contaminants such as dust, fume, gas, mist and vapour directly at their source, before they can spread into the workplace air and enter an operator’s breathing zone.

HLA Services can survey, benchmark, design and install LEV systems to help businesses control exposure to substances hazardous to health and meet their health and safety responsibilities under the Control of Substances Hazardous to Health (COSHH) Regulations.

Every year, people in the UK suffer from respiratory illness associated with exposure to hazardous substances in the workplace. Depending on the process, these substances can include:

• Organic and manufacturing dust
• Mists and solvents
• Fume
• Gases, including carbon monoxide

What are Local Exhaust Ventilation systems?

Local Exhaust Ventilation systems are designed to control airborne contaminants at the point where they are generated. Rather than allowing dust, fumes, vapours or other contaminants to spread throughout the workplace, an LEV system captures them close to the source and extracts them away from the operator.

An effective LEV system can form an important part of a workplace’s control measures where employees may be exposed to substances that are hazardous to health.

HLA Services can provide LEV services including surveying, benchmarking, system design, installation, Thorough Examination and Testing (TExT), and ongoing maintenance.

Why do businesses need LEV systems?

Businesses may require LEV where their processes generate hazardous dust, fume, gas, mist or vapour that could expose employees to substances hazardous to health.

By capturing contaminants at source, an LEV system can help to:

• Reduce employees’ exposure to airborne contaminants
• Prevent hazardous substances from spreading throughout the workplace
• Control dust, fumes, gases, mists and vapours at source
• Support businesses in meeting their COSHH responsibilities
• Maintain effective control of workplace contaminants

The correct LEV system depends on the process being carried out, the contaminant being generated and how the work is undertaken. Appropriate assessment, design, commissioning, testing and maintenance are therefore important parts of effective LEV control.

What are the risks of poor ventilation control?

Where airborne contaminants are not adequately controlled, they can spread into the workplace and increase the potential for employee exposure.

The health risks associated with poor control depend on the substance, the level of exposure and the process involved. Contaminants such as dust, fumes, gases, mists and vapours can present significant risks where they are not effectively controlled.

An appropriately designed and maintained LEV system helps to capture contaminants at source before they can spread into the general workplace environment.

Which industries use LEV systems?

LEV systems are used across a wide range of industries and processes where work activities generate hazardous dust, fumes, gases, mists or vapours.

HLA Services works with businesses across different industries and processes to help control exposure to substances hazardous to health under COSHH.

Examples of applications where LEV may be used include:

Welding and fabrication – LEV systems can capture fine metal fumes generated during welding and fabrication processes before they reach the operator’s breathing zone.

Woodworking and machining – Extraction systems can remove wood dust, chips and fine particulates generated during cutting, shaping, routing and sanding.

Metal grinding and polishing – LEV can help remove abrasive metallic dust and particles generated by mechanical power tools used for grinding and polishing.

Laser cutting and engraving – Extraction systems can help control fumes and vapours produced when materials are processed using laser cutting and engraving equipment.

Metal casting and blasting – LEV systems can help control heavy dust loading generated during processes such as casting, cleaning, fettling and blasting.

Laboratory work – Specialist extraction systems and fume cupboards can be used to control chemical vapours, gases and other hazardous substances generated during laboratory processes.

Pharmaceutical manufacturing – LEV can be used to control exposure during processes involving active powders, granulating and tablet coating.

Spray painting and coating – Extraction systems can remove paint mists and volatile organic compound (VOC) vapours generated during spraying and coating processes.

Chemical mixing – LEV systems can capture hazardous fumes and vapours generated during activities such as decanting, compounding and chemical mixing.

Vehicle exhaust extraction – Vehicle exhaust extraction systems can capture exhaust emissions at source, helping to prevent harmful gases and other contaminants from accumulating in enclosed working environments.

LEV systems and COSHH requirements

Under the UK’s Control of Substances Hazardous to Health (COSHH) Regulations, employers must identify hazardous substances present in the workplace, assess the risks associated with exposure and implement appropriate control measures.

Where hazardous airborne substances are generated, LEV can form an important part of the measures used to prevent or adequately control exposure.

Employers should ensure that LEV systems are appropriately designed, commissioned, used and maintained, with regular examination and testing to confirm that they continue to provide effective control.

HLA Services can help businesses assess their LEV requirements and maintain systems used to control exposure to substances hazardous to health.

HSG258 guidance for LEV systems

The Health and Safety Executive’s HSG258 guidance provides information on the design, commissioning, use and maintenance of Local Exhaust Ventilation systems.

HLA’s LEV services cover key areas of the guidance, including system design, commissioning, routine checks and Thorough Examination and Testing.

LEV system design

LEV systems should be designed by a competent P602 designer to ensure that contaminants are effectively captured at source before they can spread into the workplace air.

HLA can survey and benchmark existing systems and provide LEV design solutions based on the processes and contaminants present on site.

LEV system commissioning

New LEV systems should be formally commissioned by a competent P604 engineer to demonstrate that the system achieves the performance specified by its design.

HLA’s engineers have the relevant P604 competence to support businesses with LEV commissioning requirements.

Routine LEV checks

A designated person or system operator should carry out appropriate visual and airflow indicator checks whenever the LEV system is used.

Routine checks can help identify faults or changes in performance at an early stage, allowing issues to be investigated before they affect the system’s ability to control contaminants.

Thorough Examination and Testing

Under COSHH Regulation 9, LEV systems should undergo a Thorough Examination and Test (TExT) every 12 to 14 months.

The purpose of the TExT is to establish whether the LEV system continues to perform effectively and provide adequate control of the contaminants generated by the process.

HLA engineers have P601 competence to carry out LEV Thorough Examination and Testing.

LEV record keeping

Businesses should maintain appropriate records relating to their LEV systems, including maintenance records, user manuals and test reports.

These records should be retained for a minimum of five years.

Following an HLA LEV Thorough Examination and Test, customers receive a detailed report documenting the results of the examination and any remedial work identified.

How often should LEV systems be tested?

LEV systems should undergo a Thorough Examination and Test (TExT) every 12 to 14 months in accordance with the applicable COSHH requirements.

Regular testing is important because an LEV system can deteriorate over time. Changes to ductwork, hoods, fans, filters and other components can affect system performance and reduce its ability to control contaminants effectively.

In addition to the formal TExT, operators should carry out appropriate routine visual and airflow checks whenever the system is used. These checks can help identify obvious faults or changes in performance.

What is a Thorough Examination and Test (TExT)?

A Thorough Examination and Test is a detailed assessment of an LEV system to establish whether it is performing effectively and continues to provide adequate control of the contaminants generated by the process.

HLA’s LEV TExT process includes communication with site operators, visual inspection, visual testing, performance testing and detailed reporting.

Communication and site discussion

Before testing begins, HLA engineers discuss the process with site operators to understand how the LEV system is being used and the contaminant that needs to be controlled.

Understanding the process and the way the system is used is an important part of assessing whether the LEV system is providing effective control.

Visual inspection

The LEV system is visually inspected, including components such as:

• Hoods
• Ductwork
• Seals
• Fans
• Filters
• Gauges and other system components

The inspection helps identify wear, damage, blockages or other issues that could affect system performance.

Visual testing

HLA engineers can use smoke and Tyndall beam testing to assess whether contaminants are being effectively captured by the LEV hood and to identify potential escapes into the operator’s breathing zone.

Performance testing

Relevant transport velocities and pressures are measured to assess the performance of the LEV system.

HLA uses calibrated air monitoring equipment to assess system performance against the requirements of HSG258 and applicable COSHH requirements.

System alarms and filters

Gauges, alarms and filters fitted to the LEV system are checked to ensure they are operating correctly and that the system is effectively controlling the hazardous substances generated by the process.

Reporting

Once the Thorough Examination and Test has been completed, HLA provides a detailed report showing the test results.

The report confirms whether the system has passed or failed the examination, identifies any repairs or remedial work required, provides a summary of the testing undertaken and advises the customer of the next TExT due date.

LEV system survey, design, installation and testing

HLA Services can support businesses with their LEV requirements, from initial assessment and system design through to installation, testing and ongoing maintenance.

Our LEV services include:

• LEV surveys
• System benchmarking
• LEV system design
• Installation
• Commissioning
• Thorough Examination and Testing (TExT)
• Performance testing
• System maintenance
• Identification of repairs and remedial requirements

Our engineers have P601, P602 and P604 competence where relevant, allowing HLA to support businesses with LEV examination, design and commissioning requirements.

HLA’s aim is to help businesses maintain effective control of workplace contaminants while meeting their health and safety responsibilities.

HLA Services are joint distributors for Plymovent and suppliers of Camfil products, along with other leading LEV equipment manufacturers.

See our LEV case studies

From system design and installation to testing and ongoing maintenance, HLA Services supports businesses across a wide range of industries and processes.

Take a look at our LEV case studies to see examples of our work and how we’ve helped businesses improve their workplace extraction and ventilation systems.

Talk to us about your LEV system

If you need an LEV system surveyed, designed, installed, tested or maintained, contact HLA Services to discuss your requirements.

We can arrange a free site survey and assess your existing LEV arrangements, helping you understand whether your system is providing the required level of control.

Contact us today to arrange a free site survey.