With reference to the Control of Substances Hazardous to Health (COSHH), it is easy to overlook the fact that ‘substances’ extends beyond liquids and chemicals to gases, fumes and even airborne dust.
Local exhaust ventilation (LEV) systems for extracting fumes from processes such as cutting, grinding, sawing, spraying, welding, sanding and chemical handling, must therefore comply with COSHH, which is a legal requirement in the UK. And yet some LEV test houses report failure rates of 60-80%, indicating an industry-wide lack of awareness regarding LEV system requirements for COSHH compliance.
According to Adrian Sims, director of LEV testing specialist Vent-Tech and fellow of both the Institute of Plant Engineers (IPE) and Institute of Local Exhaust Ventilation Engineers (ILEVE), companies achieve COSHH compliance for their LEV systems by following HSE guidance HSG258: Controlling airborne contaminants at work.
“It’s the equivalent of the Highway Code,” he says. “As a road user, you follow the guidance document - the Highway Code - to ensure compliance with the law, namely the Road Traffic Act. Likewise, for your LEV system to comply with the law [COSHH], you follow HSG258.”
COSHH Regulation 9 states that LEV systems must undergo thorough examination and testing (TExT) at least every 14 months to ensure good working order and the effective control of exposure to hazardous substances. However, it seems there is little policing of this legal requirement.
“It’s true that no formal checking for compliance exists,” admits Sims. “However, if a problem occurs, such as an employee health issue, the HSE could ask to see your COSHH compliance. If you don’t have it, you’re on thin ice.”
PUT TO THE TEST
A thorough examination by Vent-Tech of all LEV system components - including hoods, filters and ducts - typically involves four stages. Step one is a visual check. Is everything in order? Are any components missing, are filters clogged or fans running backwards, for example?
“Moving air is quite a noisy process, so we often find companies only use their LEV system when absolutely necessary, which is when they inadvertently deteriorate,” says Sims. “If a system fails its visual inspection, we can’t move forward to stage two: qualitive testing.”
This phase involves pass or fail tests for fume and airborne dust levels. HSE guidance document EH40/200 lists workplace exposure limits for use with COSHH. The inhalable dust threshold, for example, is 10 mg/m³ of air, averaged over an 8-hour working shift.
Successfully negotiating qualitive tests allows progression to step three: quantitative testing. This data gathering stage includes the measurement of face velocity (how quickly a fume hood sucks in air), duct velocity, and pressures at the hood, fan and filters. Further measurements can include amperage loading on the motor, noise levels and lux levels.
“The inspector will often compare data sets with those recorded in the LEV system commissioning report, industry standards and HSE guidelines,” explains Sims. “A drop-off in numbers could indicate an issue.
“As a final step we issue a report that identifies any system faults and provides recommendations. It includes a certificate indicating whether your LEV system is safe to use. The employer, under COSHH Regulation 6, has a legal duty to read the report and carry out any remedial actions.”
HIRED HAND
LEV testing for COSHH compliance is not only necessary for permanent factory installations, but anywhere workers might potentially suffer expose to a health risk from airborne contaminants. It therefore includes those hiring LEV equipment.
However, Ted Taylor, senior technical consultant at fume extraction and dust control equipment hire specialist RVT Group, delivers a word of caution: “Not all hire companies offer TExT certificates, which can be worrying for those running a site. You need to ask: does the machine you’re hiring have clean filters; are the filters working properly; do the filters contain someone else’s hazardous materials now brought to your site?”
Site managers should check that hire companies have stringent maintenance and repair processes in place to ensure hire equipment is thoroughly inspected and ready for use. LEV testing is again a four-step process at RVT Group: cleaning and maintenance; electrical safety tests; performance tests; and final checks and certification.
“It’s the responsibility of the site operator to ensure the LEV hire equipment is in good order before use, with any concerns raised immediately,” says Taylor. “Ask the hire company to provide a TExT certificate, equipment instructions and maintenance guidance.”
PERSON OF INTEREST
Somewhat surprisingly, it seems LEV testing companies do not require any official accreditations or HSE approval. The only stipulation is the need for a ‘competent person’. According to the HSE, a competent person is someone who has sufficient training, experience, knowledge or other qualities to provide proper assistance.
According to Sims, a new UK association for LEV is currently in formation and should be operational shortly. Among its remits will be the introduction of a ‘competency’ scheme, with participants signing up to a charter of good practice.
In all cases, plants have a legal duty to ensure contractors are competent. They should ask to see evidence of relevant knowledge, experience and qualifications, such as P601, P602, P603, P604 modules from the British Occupational Hygiene Society. Membership of ILEVE is a further indicator of competence. Also, ask whether the contractor can provide references or independent third-party assessments.
“The duty holder should be asking these pertinent questions, rather than appointing an LEV testing provider based on little more than an attractive website,” states Sims.
PASS JUDGEMENT
Providing testimony to the general lack of industry awareness on this topic, Vent-Tech has failed between 60% and 80% of all LEV systems its inspectors have tested since the company’s formation in 2001. “Common reasons for failure include incorrect use, insufficient training, and lack of servicing and maintenance,” he says.
Due to their nature of operation, LEV systems vibrate and typically extract abrasive, corrosive, hot substances, all of which indicates a need for care.
“We also offer service contracts, but the number of LEV system tests we perform doesn’t tally with the amount of service visit requests - nowhere near - which again tells its own story.”
PICTURE OF HEALTH
Beyond the legal issues, an even more important factor is at stake when it comes to ensuring COSHH-compliant LEV systems: worker health. The International Agency for Research on Cancer classifies welding fumes, for example, as Group 1 carcinogens.
The same applies to wood dust, with the HSE stating there is no known safe level of exposure to either. Indeed, the HSE estimates around 12,000 lung disease deaths each year carry links to past exposures at work, which shines a spotlight on the importance of LEV testing for COSHH compliance.
“And there are many associated issues,” adds Sims. “The healthcare costs, for example, are enormous. We also see many workers leaving occupations where risks are evident, which is hardly helping the skills shortage.”
Ultimately, regular LEV system testing is a legal requirement and a vital step in safeguarding employee health and wellbeing. Those failing to ensure COSHH compliance could face both financial and moral consequences.