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LEV testing - composites
Laying up fibreglass and working with composite resins is everyday work in many workshops - boat building, repairs, manufacturing - and it releases something that is anything but everyday: styrene and resin fumes that are a genuine respiratory hazard. The extraction that controls them, and the test that proves it works, is what protects the people doing the work.
The short answer
Working with composite and fibreglass resins - polyester resin in particular - releases styrene and other resin fumes into the air, which are irritating and harmful to breathe, affecting the airways and more. It is a real health hazard behind an ordinary-seeming process. Local exhaust ventilation controls the fumes by capturing them at source, at the lay-up or working area, before workers breathe them - and because it controls a health hazard, the LEV must be examined and tested to confirm it is genuinely doing so. The extraction protects the workers; the test proves it.
An everyday process, a real hazard
Composite and fibreglass work - laying up glass fibre with resin, moulding composites, repairing fibreglass - is common, everyday work in many trades, from boat building to vehicle repair to manufacturing. Because it is so routine, the hazard it carries can be underestimated. But working with composite resins, particularly the polyester resins widely used in fibreglass, releases fumes into the air - notably styrene, the reactive solvent in polyester resin - and those fumes are a genuine health hazard, not just an unpleasant smell.
So an ordinary-seeming process carries a real airborne hazard. The strong smell of resin work is itself a sign of the fumes being released, and while the smell is the obvious part, the health effects are the serious part. Styrene and resin fumes are harmful to breathe, and the workers doing the lay-up or working close to the resin are exposed to them directly and repeatedly. Recognising that this everyday work releases a genuine respiratory hazard is the starting point for seeing why it needs proper control - the routine nature of the process does not make the fumes any less harmful.
What the fumes do
The fumes from composite and fibreglass work are harmful in real ways. Styrene, the main concern in polyester resin, is an irritant - it irritates the eyes, nose, throat and respiratory system, so exposure causes irritation of the airways. Beyond irritation, styrene has broader health effects with significant exposure, and it carries a workplace exposure limit precisely because it is a substance whose airborne concentration needs controlling. So the fumes are not merely unpleasant but a substance with defined health effects that exposure should be kept within limits, and reduced, to avoid.
So the workers doing resin work are exposed to a fume that harms the airways and has wider health effects, repeatedly, as part of their normal work. That is exactly the kind of situation - a harmful airborne substance released by a process, with workers exposed to it - that requires control to protect health. The everyday familiarity of resin work can obscure this, but the fumes are a genuine occupational health hazard, and the exposure has to be controlled to keep the workers safe. The harm the fumes do is the reason the control is necessary.
LEV controls it at source
The control for resin fumes, as for other harmful airborne substances, is local exhaust ventilation capturing them at source before workers breathe them. Composite and fibreglass work releases the fumes at the point of work - the lay-up area, the mould, the workpiece being worked on - and LEV captures them there, drawing the fume-laden air away before it disperses into the air the worker breathes. Extraction at the working area is how the styrene and resin fumes are captured at the point they are generated, keeping them out of the worker's breathing zone.
Because styrene has a workplace exposure limit and the fumes are harmful, the aim is to control the exposure - keeping it within the limit and reducing it as far as reasonably practicable. Effective source-capture LEV at the resin working areas is central to that, capturing the fumes where they are released. So the extraction is the primary defence for workers doing composite and fibreglass work - controlling the fumes at source, which is where they can be captured before they become an inhaled hazard. It is the control that stands between the workers and the repeated exposure to harmful resin fumes their work involves.
Testing keeps it controlled
As with any LEV, the resin fume extraction only protects the workers if it is genuinely capturing the fumes - which is what testing confirms. The extraction degrades like any system: capture is lost, ducts foul, fans tire, and the system can quietly fall below the level needed to control the fumes, with no obvious sign. A thorough examination and test measures and observes whether the system is genuinely capturing the styrene and resin fumes at source as it should, catching any shortfall before it becomes exposure. The law requires this testing because the protection cannot be assumed.
So the LEV test is what keeps the resin fume control real, by confirming the extraction is doing its job. A tested system proven to be capturing the fumes is genuinely controlling the exposure that harms the workers' airways; an untested one might be failing to, silently, leaving the workers exposed to a harmful fume without anyone knowing. For workers doing composite and fibreglass work, repeatedly exposed to styrene and resin fumes, that confirmation is what ensures the primary defence is actually working. The extraction controls the fumes, and the test proves it does - which is what protects the people doing the work.
The takeaway
Composite and fibreglass work releases styrene and resin fumes into the air - a genuine respiratory hazard behind an everyday process. Styrene irritates the airways and has wider health effects, carrying a workplace exposure limit precisely because its airborne concentration needs controlling, and the workers doing the lay-up are exposed to it directly and repeatedly. The routine nature of the work does not make the fumes any less harmful.
Local exhaust ventilation controls the fumes by capturing them at source, at the working area, before workers breathe them - the primary defence for people doing resin work. And LEV testing keeps that defence real: it confirms the extraction is genuinely capturing the fumes, catching any silent shortfall before it becomes exposure. For workers repeatedly exposed to harmful resin fumes, controlling the fumes and testing the control is exactly what protects them - the extraction doing the work, and the test proving it does.
Questions
Fumes - notably styrene, the reactive solvent in polyester resin used in fibreglass, along with other resin fumes. These are released into the air during lay-up and resin work, and are a genuine respiratory hazard, harmful to breathe, not just an unpleasant smell.
It is an irritant - irritating the eyes, nose, throat and respiratory system, so exposure irritates the airways - and it has broader health effects with significant exposure. It carries a workplace exposure limit because its airborne concentration needs controlling.
Because composite and fibreglass work is common, everyday work in many trades, so the hazard it carries can be overlooked. But the routine nature of the process does not make the fumes any less harmful - the workers doing the lay-up are exposed to a genuine health hazard repeatedly.
By capturing them at source - at the lay-up area, mould or workpiece where the fumes are released - drawing the fume-laden air away before it disperses into the air the worker breathes. Extraction at the working area keeps the styrene and resin fumes out of the breathing zone.
Because it only protects the workers if it is genuinely capturing the fumes, and it degrades - capture lost, ducts fouled, fans tired - often with no obvious sign. Testing confirms the extraction is genuinely capturing the fumes at source, catching any shortfall before it becomes exposure.
The workers doing the lay-up or working close to the resin, who are exposed to the styrene and resin fumes directly and repeatedly as part of their normal work. Boat building, fibreglass repair and composite manufacturing all involve this exposure, which the LEV is there to control.
We test the extraction controlling styrene and resin fumes in composite and fibreglass work - confirming it genuinely captures the fumes at source, so the workers doing the lay-up are protected.
