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LEV testing - bakeries
Flour dust is a respiratory sensitiser - a leading cause of occupational asthma, and something a bakery has a legal duty to control. Reducing exposure means tackling the dusty tasks with low-dust methods, capturing the dust with local exhaust ventilation, keeping good housekeeping, and using RPE where needed. Here is a practical how-to for cutting flour dust exposure in a bakery. This is general information, not a substitute for a COSHH assessment.
The short answer
Flour is everywhere in a bakery, and so is flour dust - but flour dust isn't harmless. It's a respiratory sensitiser and one of the most common causes of occupational asthma (baker's asthma), so a bakery has a legal duty under COSHH to control it and keep exposure as low as reasonably practicable. Here's a practical how-to for reducing flour dust exposure. This is general information, not a substitute for a COSHH assessment. Why it matters, briefly. Flour dust is a respiratory sensitiser: repeated breathing of it can sensitise a baker's airways, leading to baker's asthma - which, once someone is sensitised, means they react to even small amounts and often can't keep working with flour. It's a COSHH-controlled substance with a workplace exposure limit, and because it's a sensitiser, exposure should be kept as low as reasonably practicable, not just below the limit. So reducing flour dust is a real health duty (covered in the bakeries-flour-dust-in-older-premises page). Target the dusty tasks. Flour dust is raised by specific tasks, so that's where to focus. The dusty jobs: tipping and weighing flour (especially emptying sacks, which releases clouds of dust); sieving flour; adding flour to mixers; dusting work surfaces, benches, peels and dough with flour; and cleaning up (particularly dry-sweeping, which re-raises settled flour). So reducing exposure means tackling these tasks - the points where dust is generated and where bakers breathe it. Reduce the dust made: low-dust methods. First in the hierarchy, reduce the dust generated in the first place, using low-dust methods. Handle flour carefully: tip it gently rather than dropping it from height (dropping flour throws up clouds), and pour rather than shake or throw it. Use low-dust techniques and equipment where available: some processes, dispensing methods and even ingredient forms are lower-dust than others. And avoid unnecessarily dusty practices: over-dusting benches and dough, throwing flour, or vigorous handling that isn't needed. Making less dust at source is the most effective control because it reduces the problem before it starts - less dust made means less to capture, clean and breathe. Capture the dust: LEV. Then capture the dust that is made, at source, with local exhaust ventilation (LEV). Extraction at the dusty points - the tipping and weighing station, the mixer, the sieving point - draws the flour dust away as it's generated, before it reaches the baker's breathing zone or spreads through the bakery. LEV is the key engineering control for capturing the dust that low-dust methods don't prevent. And crucially, this LEV must be kept working - maintained and thoroughly examined and tested regularly (typically at least every fourteen months) - to confirm it's still capturing the dust (a degraded extraction stops protecting bakers). So LEV captures the dust at source, and testing keeps it proven. Good housekeeping. Clean up spilt and settled flour properly - and this is where a common mistake happens. Never dry-sweep or blow down with an airline (compressed air) to clean up flour, because both just throw the settled flour dust back into the air, re-creating the exposure. Instead, clean up by vacuum (a suitable vacuum) or damp methods where appropriate, so the flour is removed, not re-suspended. Keeping surfaces and floors free of flour build-up, cleaned the right way, is part of controlling the exposure. RPE and health surveillance. Use respiratory protection (RPE) - suitable, face-fit-tested masks - where the other controls don't fully control the exposure (some dusty tasks), or as a backup, but as an addition to the source controls (which protect everyone), not a substitute. And consider health surveillance for bakers: monitoring for early signs of sensitisation or respiratory effects, so anyone developing a problem is caught early (and it flags if the controls aren't working). This backs up the exposure reduction. The takeaway. So reducing flour dust exposure in a bakery means: recognise it as a sensitiser to control under COSHH (as low as reasonably practicable); target the dusty tasks (tipping, weighing, sieving, dusting, cleaning); reduce the dust made with low-dust methods (careful handling, low-dust techniques, no unnecessary dustiness); capture what's made with LEV (kept working and tested); clean up properly (vacuum, never dry-sweep or blow down); and add RPE and health surveillance. The heart of it is making less dust and capturing what's made - reduce and capture, at the dusty tasks. This is general information, not a substitute for a COSHH assessment. This is general information.
Key points
Target the dusty tasks
Flour dust is raised by specific tasks, so reducing exposure starts with knowing where to focus. The dusty jobs in a bakery: tipping and weighing flour (especially emptying sacks, which releases clouds of dust); sieving flour; adding flour to mixers; dusting work surfaces, benches, peels and dough with flour; and cleaning up (particularly dry-sweeping, which re-raises settled flour into the air). These are the points where dust is generated and where bakers, working right at them, breathe it in.
So reducing exposure means tackling these tasks specifically, rather than treating the whole bakery uniformly. The dust comes from identifiable sources, so the controls (low-dust methods, LEV) are aimed at those sources - the tipping and weighing station, the mixer, the sieving point, the dusting bench. Knowing where the dust is raised lets the effort be targeted where it counts. This is the same principle as any dust control: identify the sources, then control them. So target the dusty tasks - where the flour dust is raised - is the starting point: focus on tipping, weighing, sieving, dusting and cleaning. Reducing the dust made at those tasks is next. So focus the effort on the dust-raising tasks. This is general information, not a COSHH assessment. This is general information.
Reduce the dust made
First in the hierarchy of control, reduce the dust generated in the first place, using low-dust methods - because the most effective control is to make less dust, not just to capture more. Handle flour carefully: tip it gently rather than dropping it from height (dropping flour throws up clouds of dust), and pour rather than shake or throw it. Use low-dust techniques and equipment where available: some processes, dispensing methods and ingredient forms are lower-dust than others.
And avoid unnecessarily dusty practices: over-dusting benches and dough (using more flour than needed), throwing flour, or vigorous handling that isn't necessary. Small changes in how flour is handled can make a real difference to how much dust goes into the air. Making less dust at source is the most effective control because it reduces the problem before it starts - less dust made means less to capture, less to clean up, and less to breathe. It also makes the other controls (LEV, housekeeping) more effective, because they're dealing with less dust. So reducing the dust made comes first, and underpins everything else. So reduce the dust made - low-dust methods and careful handling - is the first and most effective control: make less dust at the dusty tasks. Capturing what's still made is next. So make less dust in the first place. This is general information, not a COSHH assessment. This is general information.
Capture the dust with LEV
Then capture the dust that is made, at source, with local exhaust ventilation (LEV). Extraction at the dusty points - the tipping and weighing station, the mixer, the sieving point - draws the flour dust away as it's generated, before it reaches the baker's breathing zone or spreads through the bakery. LEV is the key engineering control for capturing the dust that low-dust methods don't prevent, removing it at source so bakers don't breathe it.
And crucially, this LEV must be kept working to keep protecting bakers. As an LEV controlling a sensitiser, it must be maintained and thoroughly examined and tested regularly (typically at least every fourteen months) to confirm it's still capturing the dust. This matters because extraction degrades unnoticed - a weakening fan, a clogging filter - and stops capturing the dust while still appearing to run, leaving bakers exposed to a sensitiser without any obvious sign. So the LEV isn't fit-and-forget: it's maintained and tested to prove it's still working (covered in the bakery-flour-dust-how-an-lev-test-keeps-lungs-safe page). So capture the dust with LEV - extraction at source, kept working and tested - is the key engineering control: draw the dust away at the dusty tasks, and keep that extraction proven. Housekeeping and RPE back it up (next). So capture the dust at source with tested LEV. This is general information, not a COSHH assessment. This is general information.
Clean up properly
Clean up spilt and settled flour properly - and this is where a common and important mistake happens. Never dry-sweep or blow down with an airline (compressed air) to clean up flour, because both just throw the settled flour dust back into the air, re-creating the very exposure you're trying to reduce. Dry-sweeping stirs the settled flour into a cloud; blowing down blasts it into the air even more.
Instead, clean up by vacuum (a suitable vacuum) or by damp methods where appropriate, so the flour is removed rather than re-suspended. Keeping surfaces, benches and floors free of flour build-up - cleaned the right way - is part of controlling the exposure, not just tidiness, because settled flour gets re-disturbed (by movement, draughts, activity) and re-breathed. So good housekeeping, done by the right method, keeps the settled-dust exposure down and stops undoing the other controls. This is a simple rule that's easy to get wrong out of habit (grabbing a broom or an airline), so it's worth emphasising: vacuum or damp-clean, never dry-sweep or blow down. So clean up properly - vacuum, never dry-sweep or blow down - is the housekeeping control: remove settled flour without re-suspending it. RPE and health surveillance complete the picture. So clean up flour without throwing it back in the air. This is general information, not a COSHH assessment. This is general information.
RPE and health surveillance
Use respiratory protection (RPE) - suitable, face-fit-tested masks - where the other controls don't fully control the exposure (some dusty tasks may leave residual exposure), or as a backup layer. But RPE is an addition to the source controls (low-dust methods, LEV), which protect everyone in the area, not a substitute for them - it protects the individual wearer where the source controls can't fully do the job. So the layered approach is: reduce the dust, capture it at source, and use RPE for the residual, in that order of preference.
And consider health surveillance for bakers: monitoring for early signs of sensitisation or respiratory effects (through respiratory questionnaires and, as advised, lung-function tests), so anyone developing a problem is caught early - when action can protect them before it becomes established baker's asthma. Health surveillance also flags if the controls aren't working (if bakers are showing effects, the exposure controls, including the LEV, may need reviewing). So it backs up the exposure reduction, both protecting individuals and checking the controls (covered in the how-to-build-a-health-surveillance-programme page). So RPE and health surveillance - back up the controls, and catch harm early - complete the approach: RPE for residual exposure, and health surveillance as the safety net. Together with reducing and capturing the dust, they keep bakers' exposure as low as reasonably practicable. So add RPE where needed, and surveil bakers' health. This is general information, not a COSHH assessment. This is general information.
Questions
Because it's a respiratory sensitiser and a leading cause of occupational asthma (baker's asthma) - once sensitised, a baker reacts to even small amounts and often can't keep working with flour; it's COSHH-controlled with an exposure limit, and being a sensitiser, exposure must be kept as low as reasonably practicable. Flour dust needs reducing in a bakery because it's a respiratory sensitiser and one of the most common causes of occupational asthma. Repeated breathing of flour dust can sensitise a baker's airways, leading to baker's asthma - and once someone is sensitised, they react to even small amounts of flour dust, and often can't keep working with flour, so it can end their career. It's a serious, potentially career-ending health hazard, not a trivial nuisance. Flour dust is a COSHH-controlled substance with a workplace exposure limit, so a bakery has a legal duty to control exposure to it. And because it's a sensitiser, exposure should be kept as low as reasonably practicable - not just below the exposure limit - since for a sensitiser, lower is safer all the way down. So reducing flour dust is a real health-and-legal duty: to protect bakers from a sensitiser that causes an incurable, career-ending occupational asthma, and to meet the COSHH requirement to control exposure as low as reasonably practicable. This is why a bakery invests in low-dust methods, LEV, housekeeping and the rest to cut the dust. So it needs reducing because it's a sensitiser causing baker's asthma. So because it's a sensitiser that causes baker's asthma. This is general information, not a COSHH assessment. This is general information.
Tipping and weighing flour (especially emptying sacks, which releases clouds), sieving, adding flour to mixers, dusting surfaces, benches and dough, and cleaning up (especially dry-sweeping, which re-raises settled flour) - these are where the dust is generated and where bakers breathe it, so control focuses there. The dusty tasks that raise flour dust in a bakery are specific, and knowing them helps target the control. They are: tipping and weighing flour - especially emptying sacks, which releases clouds of dust; sieving flour; adding flour to mixers; dusting work surfaces, benches, peels and dough with flour; and cleaning up - particularly dry-sweeping, which re-raises settled flour dust into the air. These are the points where flour dust is generated and where bakers, working right at them, breathe it in. So reducing exposure means tackling these tasks specifically - the controls (low-dust handling methods and local exhaust ventilation) are aimed at these sources: the tipping and weighing station, the mixer, the sieving point, the dusting bench. Knowing where the dust is raised lets the effort be focused where it counts, rather than treating the whole bakery uniformly. This is the same principle as any dust control - identify the sources, then control them. So the effort concentrates on the dust-raising jobs, from tipping and sieving to dusting and cleaning. So they're tipping, weighing, sieving, mixing, dusting and cleaning. So tipping, sieving, dusting, mixing and cleaning up. This is general information. This is general information.
By using low-dust methods - handling flour carefully (tipping gently, not dropping from height, pouring not throwing), using low-dust techniques and equipment where available, and avoiding unnecessarily dusty practices like over-dusting or throwing flour; making less dust at source is the most effective control, before capturing what's made. A bakery makes less flour dust by using low-dust methods - reducing the dust generated in the first place, which is the most effective control (better than just capturing more). The main approaches: handle flour carefully - tip it gently rather than dropping it from height (dropping flour throws up clouds), and pour rather than shake or throw it; use low-dust techniques and equipment where available - some processes, dispensing methods and ingredient forms are lower-dust than others; and avoid unnecessarily dusty practices - over-dusting benches and dough (using more flour than needed), throwing flour, or vigorous handling that isn't necessary. Small changes in how flour is handled can make a real difference to how much dust goes into the air. Making less dust at source is the most effective control because it reduces the problem before it starts - less dust made means less to capture, clean up and breathe - and it makes the other controls (LEV, housekeeping) more effective by giving them less to deal with. So reducing the dust made comes first in the hierarchy, underpinning the capture and cleaning that follow. So use careful, low-dust handling to make less dust at source. So by careful, low-dust handling of flour. This is general information, not a COSHH assessment. This is general information.
Because dry-sweeping and blowing down with an airline just throw the settled flour back into the air, re-creating the exposure you're trying to reduce; clean up flour by vacuum or damp methods instead, so it's removed rather than re-suspended - settled flour that's re-raised gets breathed again. Flour shouldn't be cleaned up by dry-sweeping or blowing down with an airline because both just throw the settled flour dust back into the air, re-creating the very exposure you're trying to reduce. Dry-sweeping stirs the settled flour up into a cloud; blowing down with compressed air blasts it into the air even more forcefully. Either way, flour that had settled (and was at least out of the air) is re-suspended for bakers to breathe - undoing the dust control and exposing everyone to a cloud of the sensitiser. Instead, clean up spilt and settled flour by vacuum (a suitable vacuum, which removes the flour without re-suspending it) or by damp methods where appropriate. Keeping surfaces, benches and floors free of flour build-up - cleaned the right way - is part of controlling the exposure, because settled flour gets re-disturbed (by movement, draughts, activity) and re-breathed. So the cleaning method matters: vacuum or damp-clean, never dry-sweep or blow down. This is a simple rule that's easy to get wrong out of habit (grabbing a broom or airline), so it's worth emphasising. So because sweeping and blowing re-suspend the flour - vacuum instead. So because they throw the settled flour back into the air. This is general information. This is general information.
Yes - as an LEV controlling a sensitiser (flour dust causes baker's asthma), it must be maintained and thoroughly examined and tested regularly (typically at least every 14 months) to confirm it's still capturing the dust, because extraction degrades unnoticed and then leaves bakers exposed to a sensitiser. Yes - bakery flour dust extraction needs testing, because it's an LEV controlling a sensitiser. Flour dust causes baker's asthma (a serious, often career-ending occupational asthma), so the extraction that captures it is protecting bakers from a real health hazard. Under COSHH, LEV controlling exposure to a hazardous substance must be maintained and thoroughly examined and tested regularly - typically at least every fourteen months - to confirm it's still capturing the dust. This matters because extraction degrades over time without obvious signs: a weakening fan, a clogging filter, a blocked duct can all reduce the capture, and the system stops protecting bakers while still appearing to run. Because the dust is a sensitiser, that unnoticed under-protection is a real risk - bakers could be being sensitised without anyone realising. So the LEV can't be fit-and-forget; it has to be maintained and tested to prove it's still capturing the flour dust. The test measures the airflow and capture and checks the system, confirming it's still doing its job (covered in the bakery-flour-dust-how-an-lev-test-keeps-lungs-safe page). So yes - bakery flour dust LEV must be maintained and tested regularly. So yes; it's a sensitiser-control LEV needing regular testing. This is general information. This is general information.
Follow the hierarchy: target the dusty tasks; reduce the dust made with low-dust methods; capture what's made with LEV (kept working and tested); clean up properly (vacuum, never sweep or blow down); and add RPE and health surveillance - all to keep exposure as low as reasonably practicable for a sensitiser. The overall approach to cutting flour dust exposure follows the hierarchy of control, aimed at keeping exposure as low as reasonably practicable (because flour dust is a sensitiser). Target the dusty tasks: focus on where flour dust is raised (tipping, weighing, sieving, adding to mixers, dusting, cleaning). Reduce the dust made: use low-dust methods first - careful handling (tipping gently, not dropping from height), low-dust techniques and equipment, and avoiding unnecessarily dusty practices - because making less dust is the most effective control. Capture what's made: use local exhaust ventilation (LEV) to draw the dust away at source, kept working and thoroughly examined and tested regularly (typically at least every fourteen months) to confirm it's capturing. Clean up properly: by vacuum or damp methods, never dry-sweeping or blowing down (which re-suspend the dust). And add RPE (suitable, face-fit-tested, for residual exposure) and health surveillance (to catch early sensitisation and flag failing controls). So the approach is reduce, capture, clean and protect, at the dusty tasks - with reducing the dust and capturing what's made at its heart. So it's a layered approach of reduce, capture, clean and protect. So reduce, capture with tested LEV, clean up, and protect. This is general information, not a COSHH assessment. This is general information.
Reducing flour dust rests on capturing it at the dusty tasks with LEV that actually works - flour dust being a sensitiser that causes baker's asthma; we thoroughly examine and test bakery LEV, confirming it still captures the flour dust and protects bakers, as COSHH requires for keeping exposure as low as reasonably practicable. Ask us to test your LEV. This is general information.
