LEV testing regulations: what the law asks of you

COSHH Regulation 9

The Control of Substances Hazardous to Health Regulations 2002 (COSHH) include Regulation 9, "Maintenance, examination and testing of control measures". Where plant and equipment are provided as a control measure under Regulation 7, they must be maintained in an efficient state, in efficient working order, in good repair and in a clean condition.

For local exhaust ventilation (LEV) plant, Regulation 9(2)(a) requires thorough examination and testing "at least once every 14 months", or at not more than the specified interval for the processes in Schedule 4. Under Regulation 9(4), a suitable record of the examinations, tests and resulting repairs, or a suitable summary, "shall be kept available for at least 5 years from the date on which it was made".

These duties concern control measures. A workplace exposure limit (WEL) concerns the concentration of a substance in the air, averaged over a set period. HSE lists current GB limits in EH40. Its guidance on exposure limits explains that monitoring measures the substance in the air a worker breathes while doing a task. An airflow reading from an LEV system is not that exposure measurement.

Hazardous substances and the work that produces them

HSG258 describes airborne contaminants as particles, gases and vapours, including dusts, fumes, mists and fibres. Its examples include wood dust, silica flour and welding fume. It also describes machines used for turning, grinding and drilling that emit metalworking fluid mist. Different industries need controls matched to the material and the process, rather than a generic extraction specification.

The guidance links breathing airborne contaminants at work with occupational lung disease, including occupational asthma. Hoods need to capture the contaminant at the process, and the examiner assesses how the LEV system performs in use. Asbestos is a separate regulatory subject under the Control of Asbestos Regulations 2012. Do not use this COSHH guide as instructions for asbestos work.

Schedule 4: processes with shorter intervals

The following are the exact process descriptions in Schedule 4 and their minimum frequencies. The exceptions depend on the specified process, not simply the name of a substance or industry.

• Processes in which blasting is carried out in or incidental to the cleaning of metal castings, in connection with their manufacture. Minimum frequency: 1 month.
• Processes, other than wet processes, in which metal articles (other than of gold, platinum or iridium) are ground, abraded or polished using mechanical power, in any room for more than 12 hours in any week. Minimum frequency: 6 months.
• Processes giving off dust or fume in which non-ferrous metal castings are produced. Minimum frequency: 6 months.
• Jute cloth manufacture. Minimum frequency: 1 month.

Who holds the duty

The employer using LEV to control exposure is the duty holder. They must assess the risk, provide suitable control, maintain it and arrange the examination. HSG258 applies the same responsibilities to a self-employed person where their work with hazardous substances may harm other people. A supplier, service company or examiner also has duties for the work they provide.

HSG258 also identifies the Health and Safety at Work etc. Act 1974 among the employer's legal responsibilities. The guidance describes the employer as the system owner and employees as its users. Users should make full and proper use of the controls and report faults.

For hired on-tool extraction, HSE says the hire company owns the unit and is responsible for ensuring the examination and test has been carried out. The employer hiring it must ensure it is not used after the test expires. Check the expiry date and contact the hire company to arrange a retest or replacement before that date.

What competent means

HSE describes competence as a combination of knowledge, skills and application experience that enables someone to do an effective and reliable job. A training course alone does not make a person competent. The employer should ask about relevant training, practical experience, previous work and familiarity with the type of LEV being examined.

BOHS P601 covers the knowledge and practical work used for thorough examination and testing. HSE does not require one named qualification. Look at the whole evidence of competence. LevHQ shows qualifications claimed by listed companies and does not verify them, so ask the examiner for evidence before appointment.

The BOHS modules distinguish P600 Methods for Testing the Performance of Local Exhaust Ventilation Systems, P601 Thorough Examination and Testing of Local Exhaust Ventilation Systems, P602 Basic Design Principles of Local Exhaust Ventilation Systems, and P604 Performance Evaluation, Commissioning and Management of Local Exhaust Ventilation Systems. These describe different areas of work; a design qualification alone is not evidence of experience examining your installation.

The guidance behind the test

HSG258 is HSE's guidance for employers who use or plan to use LEV, and for suppliers of new equipment. It explains how to decide on an appropriate control, design and install the system, commission it, use it, maintain it and carry out the statutory thorough examination and test.

The guidance describes a test in three stages: a visual and structural examination, a review of technical performance against commissioning or other information, and an assessment of control effectiveness. It also describes the information an examiner needs and what the written record should contain. Following this structure makes the result more useful than a stand-alone pass label.

Keep evidence of what happened

Keep the latest thorough examination and test report available at the workplace. It should identify the system, the process and hazardous substances, its intended performance, the methods and measurements used, the result, any repairs or adjustments and any critical defects. Keep the record and records of repairs resulting from it for at least five years.

A clear maintenance log shows that findings were acted on rather than filed away. Keep repair dates, replacement parts, routine check results and any retest. A test label can help operators see the test date, next due date and a failed status, but labels are HSE guidance rather than a specific legal requirement. The report remains the main record.