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LEV testing - welding fume
Buying welding fume extraction is a start - but it's only a start. Since welding fume was reclassified as a human carcinogen, effective control is required for all welding, and that takes more than owning an extraction unit: it has to be used properly, maintained, tested, backed up with RPE, and applied to outdoor welding too. Here is what really managing welding fume involves, beyond the purchase. This is general information.
The short answer
It's easy to think that managing welding fume means buying an extraction unit - tick the box, kit bought, job done. But that's a serious under-estimate. Since welding fume was reclassified as a human carcinogen, the bar for controlling it has risen, and an extraction unit only helps if it's used, maintained, tested and backed up properly. Here's what really managing welding fume involves, beyond the purchase. This is general information. Why the bar is high: welding fume is a carcinogen. First, the context that raises the stakes. Welding fume has been reclassified as a human carcinogen: the HSE, following the international (IARC) classification, now treats all welding fume - including mild-steel fume, not just stainless or exotic alloys - as capable of causing cancer, principally lung cancer (and it also causes occupational asthma, bronchitis and metal fume fever). As a result, the HSE requires effective control of fume for all welding, and general ventilation is not considered sufficient - engineering control (LEV) is needed for welding indoors, with RPE where that's not enough. So this isn't a minor nuisance to half-manage; it's a carcinogen that must be effectively controlled for all welding. That's why buying extraction is only the start. Use it properly. Extraction only controls the fume if it's actually used - and used properly. That means: positioning it to capture the fume at source (welding fume rises on the hot plume, so the extraction hood or nozzle has to be placed to catch that rising fume, close to the work); moving or adjusting it as the work moves (fixed extraction with moving work soon isn't capturing anything); and switching it on every time. Extraction sitting unused in the corner, or a hood left the wrong side of the work, or a portable unit not moved to follow the weld, controls nothing - however good the kit. So a big part of management is ensuring the extraction is genuinely used, in the right place, every time. Maintain it. Extraction has to be maintained to keep capturing the fume. Filters clog (welding fume is fine and loads filters), the fan wears, ducts can block - so the unit's performance degrades unless it's maintained: filters changed or cleaned, the system kept in good order. A neglected extraction unit stops capturing the fume while still appearing to run, leaving the welder exposed to a carcinogen. So maintenance is essential, not optional. Test it. As an LEV controlling a carcinogen, the extraction has to be thoroughly examined and tested regularly - typically at least every fourteen months - to confirm it's still capturing the fume. This matters because extraction degrades unnoticed, and you can't see whether fine fume is being captured; the test is what proves the control is still working (covered in the lev-testing-for-welding-fume page). So testing is part of managing the fume, not an extra. Back it up with RPE. Where the extraction alone doesn't adequately control the fume - some welding positions and tasks are hard to extract fully - suitable respiratory protection (RPE) is needed on top. RPE has to be adequate for welding fume and, for tight-fitting masks, face-fit tested to the wearer. RPE protects the individual welder where the extraction (which protects the area) can't fully do the job. So managing the fume often means extraction plus RPE, not one or the other. Train and supervise welders. All of this depends on the welders. So training and supervision are part of management: welders need to understand why the fume matters (it's a carcinogen) and how to use the controls properly (position the extraction, wear the RPE, follow good practice), and supervision needs to ensure the controls are actually being used. Kit that the welders don't use, or use wrongly, doesn't protect them - so the human side is as important as the equipment. Don't forget outdoor welding. A common gap: outdoor welding still needs controlling. Welding outdoors still produces the carcinogenic fume, and the welder still breathes it (often bending over the work, right in the plume), so outdoors isn't automatically safe. Outdoor welding needs appropriate control too - typically RPE (since fixed extraction may be impractical), or portable extraction where feasible. So managing welding fume covers all welding, not just the indoor bench with the extraction unit. The takeaway. So managing welding fume properly, beyond just buying extraction, means: recognise it's a carcinogen requiring effective control for all welding; use the extraction properly (positioned, moved, switched on); maintain it; test it (as an LEV controlling a carcinogen); back it up with RPE where needed; train and supervise the welders; and control outdoor welding too. Buying the extraction is necessary but nowhere near sufficient - the management is the ongoing system that makes the fume actually controlled, and proven to be, for every weld. This is general information. This is general information.
Key points
Why the bar is high
The context that raises the stakes: welding fume has been reclassified as a human carcinogen. The HSE, following the international (IARC) classification, now treats all welding fume - including mild-steel fume, not just stainless or exotic alloys - as capable of causing cancer, principally lung cancer. Welding fume also causes occupational asthma, chronic bronchitis and metal fume fever. So it's a serious health hazard, and the cancer classification put it beyond doubt.
As a result, the HSE requires effective control of fume for all welding, and general ventilation is not considered sufficient - engineering control (local exhaust ventilation, LEV) is needed for welding indoors, with RPE where that's not enough. So the bar for controlling welding fume is high: it's not a minor nuisance to half-manage, but a carcinogen that must be effectively controlled for all welding, indoors and (appropriately) out. This is exactly why buying an extraction unit is only the start - effective control requires the extraction to actually work and be used, backed by RPE, for every weld. So why the bar is high - welding fume is a human carcinogen - sets the stakes: effective control is required for all welding, so management has to be thorough. What that management involves follows. So all welding fume is a carcinogen needing effective control. This is general information. This is general information.
Use it properly
Extraction only controls the fume if it's actually used, and used properly - a point easily missed once the kit is bought. Using it properly means: positioning it to capture the fume at source - welding fume rises on the hot plume, so the extraction hood or nozzle has to be placed to catch that rising fume, close to the work; moving or adjusting it as the work moves - fixed extraction with moving work, or a portable unit not repositioned to follow the weld, soon isn't capturing anything; and switching it on every time.
Extraction sitting unused in the corner, a hood left the wrong side of the work, or a nozzle too far from the weld controls nothing - however good the equipment. This is one of the most common failures: good extraction that isn't used, or used in the wrong position, so the fume escapes past it. So a big part of managing the fume is ensuring the extraction is genuinely used, in the right place, for every weld - which depends on the welders (training and supervision, covered below) as much as the kit. Capture at source (in the plume) is the key: the fume has to go into the extraction, not past it. So use it properly - positioned, moved, and switched on - is the first management task beyond buying: make sure the extraction actually captures the fume, every time. Maintaining it is next. So the extraction only works if it's used right, every weld. This is general information. This is general information.
Maintain it and test it
Extraction has to be maintained to keep capturing the fume. Filters clog (welding fume is fine and loads filters over time), the fan wears, ducts can block - so the unit's performance degrades unless it's maintained: filters changed or cleaned, the system kept in good order. A neglected extraction unit stops capturing the fume while still appearing to run, leaving the welder exposed to a carcinogen without any obvious sign. So maintenance is essential, not optional.
And as an LEV controlling a carcinogen, the extraction has to be thoroughly examined and tested regularly - typically at least every fourteen months - to confirm it's still capturing the fume. This matters because extraction degrades unnoticed, and you can't see whether the fine fume is being captured; the test is what proves the control is still working (covered in the lev-testing-for-welding-fume-what-good-capture-looks-like page). Maintenance keeps the extraction working; testing confirms it is. Both are part of managing the fume - a bought extraction unit that's never maintained or tested can quietly stop protecting the welder, which for a carcinogen is a serious failure. So maintain it and test it - keep it capturing, and prove it does - is the second management task: sustain and verify the extraction's performance. RPE as backup is next. So maintain the extraction and test it to prove it works. This is general information. This is general information.
Back it up with RPE and training
Where the extraction alone doesn't adequately control the fume - some welding positions and tasks are hard to extract fully - suitable respiratory protection (RPE) is needed on top. RPE has to be adequate for welding fume and, for tight-fitting masks, face-fit tested to the individual wearer. RPE protects the individual welder where the extraction (which protects the area) can't fully do the job - so managing the fume often means extraction plus RPE, not one or the other, especially given the fume is a carcinogen where residual exposure matters.
And all of this depends on the welders, so training and supervision are part of management. Welders need to understand why the fume matters (it's a carcinogen) and how to use the controls properly - positioning the extraction in the plume, wearing and fitting the RPE, following good practice (like not putting their head in the plume). And supervision needs to ensure the controls are actually being used, every time. Kit that welders don't use, or use wrongly, doesn't protect them - so the human side (understanding, correct use, supervision) is as important as the equipment. So back it up with RPE and training - protect the welder, and make sure controls are used - is the third management task: add RPE where needed, and ensure the welders understand and use the controls. Outdoor welding is the last, often-forgotten piece. So add RPE where needed, and make sure welders use it all. This is general information. This is general information.
Don't forget outdoor welding
A common gap in managing welding fume: outdoor welding still needs controlling. It's tempting to assume that welding outdoors is fine because the air is open - but welding outdoors still produces the carcinogenic fume, and the welder still breathes it, often bending over the work with their head right in the rising plume. So outdoors isn't automatically safe - the welder can still be heavily exposed to the fume close to the weld, regardless of the open air around them.
So outdoor welding needs appropriate control too. Since fixed extraction is often impractical outdoors, this typically means suitable RPE (adequate for welding fume, face-fit tested) for the welder, or portable extraction where feasible. The key point is that outdoor welding isn't exempt from the need to control the fume - the carcinogenic fume and the welder's exposure to it are the same outdoors as in, at the point of welding. So managing welding fume covers all welding - the indoor bench with the extraction unit, and the outdoor job with RPE - not just the obvious indoor case. Overlooking outdoor welding is a real gap that leaves welders exposed to a carcinogen. So don't forget outdoor welding - outdoors isn't automatically safe - completes the management: control the fume for all welding, indoors and out. So managing welding fume means controlling it everywhere it's produced. So control outdoor welding fume too - it isn't exempt. This is general information. This is general information.
Questions
Because extraction only controls the fume if it's used properly, maintained, and tested - and often needs RPE on top and to cover outdoor welding too; welding fume is now a carcinogen requiring effective control for all welding, so owning a unit that's unused, unmaintained or untested doesn't protect welders. Buying welding fume extraction isn't enough because owning the equipment doesn't, by itself, control the fume - the extraction only protects welders if it's actually used properly, maintained, and tested, and backed up where needed. Welding fume has been reclassified as a human carcinogen (all welding fume, including mild steel), so effective control is required for all welding, and general ventilation isn't sufficient. Against that bar, a bought extraction unit fails to protect welders if: it's not used, or used in the wrong position (a hood the wrong side of the rising plume captures nothing); it's not maintained (clogged filters and a worn fan stop it capturing); it's not tested (so its degradation goes unnoticed, since you can't see whether fine fume is captured); RPE isn't added where the extraction alone can't fully control the fume; welders aren't trained to use it; or outdoor welding is overlooked. So managing welding fume is an ongoing system - use, maintain, test, protect, train, cover all welding - of which buying the extraction is only the necessary first step. So buying it is necessary but nowhere near sufficient. So because it must be used, maintained, tested and backed up to actually work. This is general information. This is general information.
Yes - the HSE, following the international (IARC) classification, treats all welding fume, including mild-steel fume, as a human carcinogen capable of causing cancer (principally lung cancer); it also causes asthma, bronchitis and metal fume fever, so effective control is required for all welding, with general ventilation not sufficient. Yes - all welding fume is now classified as a human carcinogen. The HSE, following the international (IARC) classification, treats all welding fume as capable of causing cancer - and crucially, this includes mild-steel fume, not just fume from stainless steel or exotic alloys as was once thought. The principal cancer risk is lung cancer (with a possible link to kidney cancer). Welding fume also causes other serious health effects: occupational asthma, chronic bronchitis, and metal fume fever. Because of the carcinogen classification, the HSE requires effective control of fume for all welding, and general ventilation is not considered sufficient - engineering control (local exhaust ventilation, LEV) is needed for indoor welding, with RPE where that's not enough, and control is needed for outdoor welding too. So the reclassification raised the bar: welding fume is a carcinogen that must be effectively controlled for every weld, regardless of the metal or the duration. This is the reason managing welding fume properly (beyond just buying extraction) matters so much. So yes - all welding fume, including mild steel, is a carcinogen. So yes; the HSE treats all welding fume as carcinogenic. This is general information. This is general information.
Positioned to capture the fume at source - in the rising plume, close to the work - moved or adjusted as the work moves, and switched on every time; extraction unused, left the wrong side of the work, or too far from the weld captures nothing, so proper use (which depends on the welders) is essential, not just owning the kit. Welding fume extraction should be used properly by positioning it to capture the fume at source, moving it with the work, and switching it on every time. Positioning: welding fume rises on the hot plume, so the extraction hood or nozzle has to be placed to catch that rising fume, close to the work - in the plume, not to the side of it or too far away. Moving it: as the work moves, the extraction has to be moved or adjusted to keep capturing (fixed extraction with moving work, or a portable unit not repositioned to follow the weld, soon captures nothing). Switching it on: every time, for every weld. The reason this matters is that extraction unused (sitting in the corner), in the wrong position (a hood the wrong side of the work), or too far from the weld controls nothing - however good the equipment. Proper use is one of the most common failure points: good extraction defeated by poor use. And it depends on the welders, so training and supervision are needed to ensure the extraction is genuinely used, in the right place, every time. So proper use means capturing the fume at source, following the work, always on. So position it in the plume, move it with the work, always on. This is general information. This is general information.
Often yes - where the extraction alone doesn't adequately control the fume (some positions and tasks are hard to extract fully), suitable, face-fit-tested RPE is needed on top; the extraction protects the area, RPE protects the individual welder for the residual fume, and for a carcinogen residual exposure matters. Often yes - welders still need RPE where the extraction alone doesn't adequately control the fume. Some welding positions and tasks are hard to extract fully (awkward positions, confined spaces, work where the extraction can't be positioned ideally), so even with extraction in use, some fume can reach the welder. Because welding fume is a carcinogen, that residual exposure matters, so suitable respiratory protection (RPE) is needed on top of the extraction to protect the welder from what the extraction doesn't catch. The RPE has to be adequate for welding fume and, for tight-fitting masks, face-fit tested to the individual wearer (so it seals properly). The relationship is: the extraction protects the area (capturing the bulk of the fume at source), and RPE protects the individual welder for the residual fume the extraction can't fully control. So managing the fume often means extraction plus RPE together, not one or the other - the extraction reducing the fume, the RPE covering the remainder. Whether RPE is needed, and what, depends on how well the extraction controls the fume for the specific work. So often yes - RPE backs up the extraction for residual fume. So often yes, where extraction alone isn't enough. This is general information. This is general information.
Yes - welding outdoors still produces the carcinogenic fume, and the welder still breathes it (often with their head in the rising plume), so outdoors isn't automatically safe; it needs appropriate control, typically suitable face-fit-tested RPE (since fixed extraction is often impractical), or portable extraction where feasible. Yes - outdoor welding needs fume control, and assuming it doesn't is a common and dangerous gap. It's tempting to think welding outdoors is fine because the air is open, but welding outdoors still produces the carcinogenic fume, and the welder still breathes it - often bending over the work with their head right in the rising plume, close to the weld. So the welder can be heavily exposed to the fume at the point of welding, regardless of the open air around them. Outdoors isn't automatically safe. So outdoor welding needs appropriate control too. Since fixed extraction is often impractical outdoors, this typically means suitable RPE (adequate for welding fume, and face-fit tested) for the welder, or portable extraction where feasible. The key point is that outdoor welding isn't exempt from the need to control the fume - the carcinogenic fume and the welder's close exposure to it are the same outdoors as indoors, at the point of welding. So managing welding fume properly covers all welding, including outdoor jobs - overlooking them leaves welders exposed to a carcinogen. So yes - outdoor welding needs control, usually RPE. So yes; outdoors still produces the carcinogenic fume. This is general information. This is general information.
An ongoing system, not a purchase: recognising it's a carcinogen needing control for all welding; using the extraction properly (positioned, moved, on); maintaining and testing it; backing it with RPE where needed; training and supervising welders; and controlling outdoor welding too - buying the extraction is only the necessary first step. Really managing welding fume involves an ongoing system, not a one-off purchase. It means: recognising the stakes - welding fume is a human carcinogen (all welding fume, including mild steel), so effective control is required for all welding, with general ventilation not sufficient; using the extraction properly - positioned to capture the rising fume at source, moved with the work, and switched on every time (unused or misplaced extraction controls nothing); maintaining it - keeping the filters, fan and ducts in order so it keeps capturing; testing it - as an LEV controlling a carcinogen, having it thoroughly examined and tested regularly (typically at least every fourteen months) to confirm it still captures the fume; backing it up with RPE - suitable, face-fit-tested protection where the extraction alone doesn't adequately control the fume; training and supervising welders - so they understand why it matters and use the controls properly, every time; and not forgetting outdoor welding - which still produces the carcinogenic fume and needs controlling. So buying the extraction is the necessary first step, but the management is the ongoing system - use, maintain, test, protect, train, cover all welding - that makes the fume actually controlled and proven to be. So it's an ongoing system of use, maintenance, testing, RPE, training and full coverage. So an ongoing system, not just a purchase. This is general information. This is general information.
Welding fume is a carcinogen, so its extraction must actually capture the fume and keep doing so - buying it isn't enough; we thoroughly examine and test welding fume LEV, confirming it still captures the fume as it should, one essential part of managing welding fume properly, as the carcinogen classification demands. Ask us to test your LEV. This is general information.
