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LEV testing - competence
The law does not just require an LEV examination - it requires it to be done by a competent person. That word carries real weight: an examination is only as good as the competence behind it, and a valid one needs genuine, recognised competence, not just someone with a meter.
The short answer
An LEV thorough examination and test must, by law, be carried out by a competent person - someone with the knowledge, training and experience to examine and test LEV properly. Competence for this is defined by recognised criteria: the HSE's guidance (HSG258) sets out what competence looks like, and the BOHS P601 qualification is the recognised standard for competence in LEV examination in the UK. A valid examination needs that genuine competence, because an examination is only as reliable as the competence of the person carrying it out.
The law requires competence
The legal requirement for LEV is not simply that it is examined and tested, but that this is done by a competent person. That distinction matters: the law specifies competence because an examination is only meaningful if the person doing it knows how to do it properly - how to assess whether the system is genuinely controlling exposure, what to measure and observe, and how to interpret the results. An examination by someone without that competence is not a valid examination in any real sense, because it cannot reliably determine whether the LEV works.
So the question of who can carry out an LEV examination is not just about having access to instruments - it is about competence. Anyone can point a meter at a hood, but a proper thorough examination requires understanding the system, the contaminant, the required performance, and how to assess all of it - which is competence, not equipment. The law requiring a competent person is recognising that the value of an examination lies entirely in the competence behind it. Understanding what that competence means is understanding who is actually qualified to examine LEV validly.
What competence means
Competence for LEV examination means having the knowledge, training and experience to examine and test the system properly. It requires understanding how LEV works and how to assess whether it is controlling exposure - knowing what to measure (capture velocities, airflows, pressures), what to observe (whether the contaminant is actually captured), what the results should be for the contaminant, and how to judge whether the system is performing. It also requires the ability to identify faults and their causes, and to report the findings meaningfully.
This is a genuine body of expertise, not a casual skill. A competent examiner brings knowledge of the principles of LEV and airborne contaminant control, training in the methods of examination and testing, and the experience to apply them to real systems and interpret what they find. That combination is what allows a valid, reliable examination - one that genuinely determines whether the LEV controls exposure. Competence is the whole basis of a worthwhile examination, which is why it is defined and required rather than left to chance. The examination's reliability rests entirely on the examiner having this real competence.
The recognised standard
Competence for LEV examination is not left vague - it is defined by recognised criteria. The HSE's guidance HSG258, Controlling Airborne Contaminants at Work, sets out what competence in LEV examination looks like, providing the framework for what a competent examiner should know and do. And the recognised qualification that demonstrates this competence in the UK is the BOHS P601 - the British Occupational Hygiene Society's qualification in the thorough examination and testing of LEV systems, which is the standard the industry points to for LEV examiner competence.
So there is a clear, recognised benchmark for who is competent to examine LEV: an examiner meeting the HSG258 competence criteria, with recognised training such as the BOHS P601 qualification, is demonstrably competent to carry out the thorough examination and test. This gives a concrete answer to the question of competence rather than leaving it to judgement - the P601 is the recognised standard for competence in LEV examination. An examiner holding it, and the competence it represents, is one whose examination can be relied upon as genuinely valid.
Why it matters to you
The reason competence matters to you, as the operator relying on the examination, is twofold. First, a competent examination is a valid one - it genuinely determines whether your LEV is controlling exposure, so you can rely on the result. An examination by someone not truly competent might miss a system that is failing, leaving you with a false assurance and workers exposed, or might not properly assess the system at all. The competence behind the examination is what makes its conclusion trustworthy - and the conclusion is the whole point of having it done.
Second, a competent examination is a defensible one. The law requires the examination by a competent person, so having it done by a recognised, competent examiner is what satisfies that requirement - an examination by someone lacking the competence the law requires may not properly discharge the duty. So using a genuinely competent examiner, with recognised competence such as the P601 qualification, protects you on both fronts: it gives you a reliable answer about your LEV, and it satisfies the legal requirement for a competent examination. Choosing competence is choosing an examination you can both rely on and stand behind.
The takeaway
An LEV thorough examination must, by law, be carried out by a competent person - and that is not just anyone with a meter, but someone with the genuine knowledge, training and experience to examine and test LEV properly. Competence is defined by recognised criteria: the HSE's HSG258 sets out what it looks like, and the BOHS P601 qualification is the recognised standard for LEV examiner competence in the UK.
That competence matters because an examination is only as reliable as the competence behind it. A competent examination is valid - it genuinely determines whether your LEV controls exposure, so you can rely on the result - and defensible, satisfying the legal requirement for a competent person. An examination by someone lacking that competence may miss a failing system or fail to discharge the duty. So who is competent to examine LEV is not a technicality but the whole basis of a worthwhile examination: a genuinely competent examiner, with recognised competence such as P601, is what makes the examination one you can trust and stand behind.
Questions
By law, a competent person - someone with the knowledge, training and experience to examine and test LEV properly, not just anyone with a meter. Competence is defined by recognised criteria, with the BOHS P601 qualification the recognised standard in the UK.
Having the knowledge (how LEV works and how to assess it), training (in the methods of examination and testing), and experience (applying them to real systems) to genuinely determine whether the LEV controls exposure - knowing what to measure and observe and how to interpret it.
The British Occupational Hygiene Society's qualification in the thorough examination and testing of LEV systems - the recognised standard the industry points to for LEV examiner competence in the UK. An examiner holding it is demonstrably competent to carry out the examination.
HSG258, the HSE's guidance Controlling Airborne Contaminants at Work, sets out what competence in LEV examination looks like - the framework for what a competent examiner should know and do. Meeting its competence criteria is part of being a competent examiner.
Because an examination is only as reliable as the competence behind it. A competent examination genuinely determines whether your LEV controls exposure, so you can rely on it; one by someone not truly competent might miss a failing system, leaving a false assurance.
Yes - the law requires the thorough examination and test to be carried out by a competent person. Using a recognised, competent examiner (with competence such as the P601 qualification) is what satisfies that requirement; one lacking that competence may not properly discharge the duty.
We carry out LEV thorough examinations with genuine, recognised competence - so your examination is valid, reliable, and satisfies the legal requirement for a competent person.
