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LEV testing - COSHH assessments
A COSHH assessment often gets reduced to a form filled in and filed - a box ticked. But done properly, it is a genuine look at the hazardous substances in your work, who is exposed, and how to control them. Understanding how a COSHH assessment should actually be done, rather than merely completed, is what makes it protect people instead of just satisfying paperwork.
The short answer
A COSHH assessment, done properly, works through the hazardous substances in your work systematically: identify the substances and the hazards they present; work out who could be exposed, how, and how much; evaluate the risk that exposure creates; decide the control measures needed to prevent or adequately control it, working down the hierarchy of control from elimination through engineering controls like LEV to protective equipment; record the assessment and the controls; and review it when things change. The point is not to complete a form but to genuinely understand and control the risk - so the assessment is a real piece of thinking about the substances and their control, not a document produced for its own sake.
Not a form to file
The COSHH assessment has a reputation as paperwork - a form to fill in and file so that a box is ticked and the requirement met. This reputation is the enemy of doing it properly, because an assessment approached as a form to complete tends to become exactly that: a document produced to exist, rather than a genuine examination of the risk. And an assessment that is merely a completed form does little to protect anyone, because the protection comes from the thinking, not the paper. So the first thing to understand about how a COSHH assessment should be done is that it is a real assessment - a genuine look at the hazardous substances and their control - not a form-filling exercise.
The distinction matters because COSHH requires the assessment as the foundation of controlling exposure, and that foundation has to be real to bear weight. The purpose of the assessment is to understand the risk well enough to control it properly - which requires actually thinking about the substances, the exposures and the controls, not just recording generic statements on a form. An assessment done as real thinking produces genuine understanding and appropriate controls; one done as paperwork produces a document and little else. So doing a COSHH assessment properly means approaching it as the substantive exercise it is meant to be, with the form as the record of that thinking rather than the point of it.
Identify and evaluate
A proper COSHH assessment starts by identifying the hazardous substances involved in the work - the chemicals used, and the dusts, fumes, vapours or other hazardous things generated by the processes - and understanding the hazards each presents. This means knowing what the substances are and how they can harm health, drawing on the information available about them, such as safety data sheets for chemicals and knowledge of what processes generate. You cannot assess a risk you have not identified, so this identification of the substances and their hazards is the essential first step.
Next comes working out the exposure and evaluating the risk. This means considering who could be exposed to each substance, how they could be exposed - breathing it in, skin contact, and so on - and how much, given how the work is done. From this, the assessment evaluates the risk: how likely and how serious harm is, given the hazard and the exposure. This is the analytical heart of the assessment - understanding not just that a substance is hazardous but what actual risk it poses to the actual people doing the actual work, which depends on the exposure as much as the hazard. A substance can be hazardous but well contained, or moderately hazardous but heavily encountered; the assessment works out the real risk in the real situation, which is what the controls then have to address.
Decide the controls
With the risk understood, the assessment decides the control measures needed to prevent or adequately control exposure - and this should follow the hierarchy of control, working from the most effective options down. The first question is whether the hazardous substance or the exposure can be eliminated - the process changed so it is not used or generated at all - or substituted with something safer. These are the best controls, because they remove or reduce the hazard at its root, and a proper assessment considers them first rather than jumping straight to managing the exposure.
Where elimination and substitution are not reasonably possible, the assessment moves to engineering controls - measures like LEV that capture or contain the substance at source - then to ways of working that reduce exposure, and finally to personal protective equipment as the last line. LEV features here as a key engineering control for airborne substances, decided upon where capturing the contaminant at source is the appropriate way to control exposure. The assessment thus determines, for each risk, the appropriate controls by working down the hierarchy - and this is where the assessment translates into actual protection, because the controls it specifies are what will keep people safe. Deciding controls properly, following the hierarchy, is what makes the assessment produce genuine protection rather than a generic list of precautions.
Record, use and review
The assessment must be recorded - and this is where the form legitimately comes in, as the record of the real assessment that was done. Recording the assessment captures what substances were identified, what risks were found, and what controls were decided, so there is a documented basis for the controls in place and evidence that the assessment was carried out. But the record is the output of the assessment, not its substance: it documents the thinking that was done, rather than substituting for it. A good record reflects a real assessment; a form filled in without the underlying thinking records nothing of value.
Crucially, the assessment is not a one-off - it must be used and reviewed. Used, in that the controls it specifies are actually put in place and maintained, including keeping engineering controls like LEV working and tested, so the assessment translates into real protection rather than sitting on a shelf. Reviewed, in that it is revisited when things change - a new substance, a changed process, new information about a hazard - so it stays current rather than becoming outdated. An assessment that is done well but never acted on or updated loses its value; one that drives the controls and is kept current genuinely protects people over time. So doing a COSHH assessment properly extends beyond the initial exercise to using it and keeping it live - which is what makes it an ongoing protection rather than a document that was once produced.
The takeaway
A COSHH assessment done properly is a genuine examination of the hazardous substances in your work, not a form filled in and filed. It works through the risk systematically: identify the substances and their hazards; work out who is exposed, how, and how much; evaluate the actual risk in the real situation; and decide the controls needed, following the hierarchy of control from elimination and substitution through engineering controls like LEV to protective equipment as a last line. The point is to understand and control the risk, with the form as the record of that thinking rather than its substance.
And the assessment has to be used and kept live - the controls it specifies actually put in place and maintained, including keeping LEV working and tested, and the assessment reviewed when things change. An assessment approached as paperwork protects no one; one done as real thinking, driving real controls, and kept current genuinely protects people. So how a COSHH assessment should actually be done comes down to treating it as the substantive exercise it is meant to be - a real look at the substances and their control - which is what turns it from a box ticked into protection that works.
Questions
A genuine examination of the hazardous substances in your work and how to control them - identifying the substances and their hazards, working out who is exposed and how, evaluating the risk, and deciding the controls needed. Done properly it is real thinking about the risk, not a form filled in and filed.
Because the protection comes from the thinking, not the paper. An assessment approached as a form to complete becomes a document produced to exist, which protects no one. COSHH requires the assessment as the foundation for controlling exposure, and that foundation has to be real - actual thinking about the substances, exposures and controls - to bear weight.
Identify the hazardous substances involved and the hazards each presents, drawing on information like safety data sheets. Then work out who could be exposed, how, and how much, given the work; and evaluate the risk - how likely and serious harm is, given the hazard and the exposure. This establishes the real risk in the real situation.
Follow the hierarchy of control from most effective down: first consider eliminating the substance or substituting something safer; then engineering controls like LEV that capture it at source; then ways of working that reduce exposure; and finally protective equipment as a last line. The assessment determines the appropriate controls for each risk this way.
Yes - the record captures what substances were identified, what risks were found, and what controls were decided, documenting the basis for the controls and evidencing the assessment. But the record is the output of a real assessment, not a substitute for it: a form filled in without the underlying thinking records nothing of value.
No. It must be used - the controls it specifies actually put in place and maintained, including keeping LEV working and tested - and reviewed when things change, such as a new substance or a changed process. An assessment never acted on or updated loses its value; one that drives the controls and stays current genuinely protects people over time.
Where your COSHH assessment specifies LEV as the control, our thorough examination keeps that control working and proven - the part of using the assessment that turns it into real, maintained protection.
