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LEV testing - the skin side of COSHH
It is easy to think of hazardous substances mainly in terms of what workers breathe - and LEV is all about that airborne route. But substances harm the skin too, and occupational dermatitis is one of the most common work-related illnesses there is. It is the skin side of COSHH - a route that LEV does not address, and that needs its own controls.
The short answer
COSHH covers exposure to hazardous substances by all routes, not just inhalation - and the skin is a major one. Occupational contact dermatitis is one of the most common work-related illnesses: it comes in two forms, irritant contact dermatitis (from repeated contact with irritants like detergents, solvents, soaps, weak acids and alkalis, dusts, and wet work) and allergic contact dermatitis (from becoming sensitised to a specific substance). Because it is a skin-route harm, LEV - which controls the airborne route - does not address it. Dermatitis needs its own controls: avoiding skin contact, gloves and protective equipment, and skin care. It is a reminder that controlling hazardous substances means all routes of exposure, not only what workers breathe.
Not only what workers breathe
When we think about hazardous substances at work, the airborne route tends to dominate - the dusts, fumes and vapours workers breathe in, which LEV is designed to control. But inhalation is not the only way a hazardous substance harms the body. The skin is a major route of exposure too: substances that contact the skin can damage it directly, and some can be absorbed through it. So controlling hazardous substances properly means attending to the skin route as well as the airborne one - and the harm that comes through the skin is real and common, not a marginal concern.
This matters because a focus on the airborne route alone can leave the skin route neglected. A workplace that has good LEV controlling what workers breathe might still be exposing their skin to harm, because the two are different routes needing different controls. LEV, for all its importance, deals only with the airborne route; it does nothing for skin exposure. So the skin side of hazardous substances - and occupational dermatitis, the illness it most commonly causes - deserves attention in its own right, as a part of controlling hazardous substances that the airborne focus can overlook. COSHH covers all routes of exposure, and the skin is one that must not be forgotten.
What occupational dermatitis is
Occupational dermatitis is inflammation of the skin caused by contact with substances at work, and it is one of the most common work-related illnesses there is - occupational contact dermatitis being the most frequent occupational skin disease. It typically affects the hands, which are most in contact with substances, causing dryness, redness, itching, cracking and soreness that can become severe and persistent. It is not a trivial condition: it can be painful, disabling for work that needs the hands, and difficult to resolve once established, sometimes ending careers in affected trades. Its commonness and its impact make it a significant occupational health issue.
It comes in two main forms. Irritant contact dermatitis results from repeated contact with substances that irritate the skin - detergents, solvents, soaps, weak acids and alkalis, dusts, and notably wet work, where prolonged or frequent wetting of the skin (or frequent hand washing) itself damages the skin's protective barrier. Allergic contact dermatitis is different: it results from the skin becoming sensitised to a specific substance, so that once sensitised, further contact triggers a reaction. Both are caused by contact between the skin and substances at work, and both are covered by COSHH as harm from hazardous substances - just harm through the skin rather than the lungs. Understanding these two forms is understanding the skin side of hazardous-substance exposure.
Why LEV does not address it
The key point connecting dermatitis to LEV is a negative one: LEV does not address skin exposure. LEV controls the airborne route - it captures dust, fume and vapour so workers do not breathe them - which is essential for the inhalation hazard but does nothing for substances that contact the skin. A worker can be well protected from breathing a substance by good LEV while their skin is still exposed to it through direct contact. So LEV, however effective at its job, is simply not the control for the skin route; dermatitis is a hazard it leaves untouched, because it is a different route of exposure.
This is an important corrective to any assumption that controlling the airborne hazard controls the substance entirely. It does not - it controls one route. The skin route needs its own controls: avoiding skin contact with the substance in the first place, wherever possible; gloves and protective equipment suited to the substance where contact cannot be avoided; and skin care, including proper washing and the use of skin creams, to protect and maintain the skin's barrier. These are quite different from LEV, addressing contact rather than inhalation. So a workplace controlling a hazardous substance properly needs both: LEV for what workers might breathe, and skin-contact controls for what might reach their skin. Neglecting the skin controls because the LEV is good leaves the dermatitis risk uncontrolled.
Controlling all routes
The broader lesson is that controlling hazardous substances under COSHH means controlling all routes of exposure, not just the one LEV handles. COSHH is about protecting workers from harm by hazardous substances however that harm occurs - through the lungs, the skin, or otherwise - so a proper COSHH approach considers every route a substance can harm by and controls each appropriately. For the airborne route, that is often LEV; for the skin route, it is avoiding contact, protective equipment and skin care. A complete control approach addresses both, because a substance that harms by both routes is only partly controlled if only one route is addressed.
So occupational dermatitis stands as a reminder that hazardous-substance control is broader than the airborne focus that LEV embodies. LEV is vital for what it does, but what it does is control inhalation - and a workplace that stops there has left the skin route, and the very common harm of dermatitis, uncontrolled. Recognising dermatitis as the skin side of COSHH prompts the fuller approach: assess how a substance can harm, including through the skin, and control each route. This does not diminish LEV, which remains essential for the airborne hazard; it places it correctly as one part of controlling hazardous substances, alongside the skin-contact controls that address the route LEV cannot. Controlling the whole exposure - all routes - is what COSHH actually requires, and dermatitis is the reminder not to forget the skin.
The takeaway
COSHH covers exposure to hazardous substances by all routes, and the skin is a major one - occupational contact dermatitis is one of the most common work-related illnesses. It comes in two forms: irritant contact dermatitis, from repeated contact with irritants like detergents, solvents, soaps, weak acids and alkalis, dusts and wet work; and allergic contact dermatitis, from becoming sensitised to a specific substance. Both harm the skin through contact, and both are covered by COSHH as harm from hazardous substances.
Crucially, LEV does not address this - it controls the airborne route, capturing what workers might breathe, and does nothing for what contacts their skin. So dermatitis needs its own controls: avoiding skin contact, gloves and protective equipment, and skin care to protect the skin's barrier. A workplace controlling a hazardous substance properly needs both LEV for inhalation and skin-contact controls for the skin. Occupational dermatitis is the reminder that controlling hazardous substances means all routes of exposure, not only what workers breathe - which is what COSHH actually requires.
Questions
Yes. COSHH covers exposure to hazardous substances by all routes, not just inhalation - and the skin is a major one. Substances that contact the skin can damage it directly or be absorbed through it, so controlling hazardous substances properly means attending to the skin route as well as the airborne one.
Inflammation of the skin caused by contact with substances at work - one of the most common work-related illnesses, and the most frequent occupational skin disease. It typically affects the hands, causing dryness, redness, itching, cracking and soreness that can become severe, persistent, and difficult to resolve once established.
Irritant contact dermatitis, from repeated contact with substances that irritate the skin - detergents, solvents, soaps, weak acids and alkalis, dusts, and wet work, where prolonged wetting or frequent hand washing damages the skin's barrier; and allergic contact dermatitis, from the skin becoming sensitised to a specific substance so further contact triggers a reaction.
Because LEV controls the airborne route - it captures dust, fume and vapour so workers do not breathe them - and does nothing for substances that contact the skin. A worker can be well protected from breathing a substance by good LEV while their skin is still exposed to it. Dermatitis is a different route that LEV leaves untouched.
The skin route needs its own controls: avoiding skin contact with the substance wherever possible; gloves and protective equipment suited to the substance where contact cannot be avoided; and skin care, including proper washing and skin creams, to protect and maintain the skin's barrier. These address contact rather than inhalation, unlike LEV.
That controlling hazardous substances under COSHH means controlling all routes of exposure, not just the airborne one LEV handles. A substance that harms by both breathing and skin contact is only partly controlled if only one route is addressed - so a proper approach needs both LEV for inhalation and skin-contact controls for the skin.
LEV controls what workers breathe - one route of a hazardous substance. Our thorough examination keeps that control working, as part of a COSHH approach that must also address the skin route LEV cannot.
