This page explains the harm flour dust can cause for bakers. There is guidance on how to control the risks, including using low-dust flour.
Risks from flour dust
Flour dust is a hazardous substance as defined under the Control of Substances Hazardous to Health (COSHH) Regulations.
It can cause:
- asthma if a worker becomes sensitised, resulting in breathlessness, tightness in the chest, wheezing and bronchitis
- irritation to the eyes (conjunctivitis) resulting in watering, painful eyes
- irritation to the nose (rhinitis), resulting in a runny nose
- occupational dermatitis, resulting in redness, itching and blistering of the skin
Baker’s asthma
Breathing in traditional wheat flour dust at work is one of the main causes of baker’s asthma. This can become a disabling disease, affecting not only a baker’s health but also their ability to continue working.
Employers must therefore take action and reduce exposure to flour dust to as low a level as is reasonably practicable.
Flour dust has been set a workplace exposure limit (WEL):
- a long-term exposure limit of 10mg/m3 (averaged over 8 hours)
- a short-term exposure limit of 30mg/m33 (averaged over 15 minutes)
However, flour dust is an asthmagen and exposure should therefore be reduced as far below the WEL as is reasonably practicable.
By adopting good control practice, HSE considers that less than 2mg/m3 (averaged over 8 hours) is usually achievable. Guidance on engineering controls and good working practices to prevent dust becoming airborne is available from the Federation of Bakers.
Some bakery additives/bread improvers contain enzymes (for example fungal alpha amylase) which are potent sensitisers, so exposure to them should be minimised. This may be achieved by using improvers in liquid, paste or dust suppressed powder form.
Low-dust flour can reduce asthma risks
If a bakery cannot use non-stick surfaces and must use flour as a lubricant to stop dough sticking to tables and conveyors, a low-dust flour can be used in sieves and dredgers and has been seen to generate less dust than normal flour when handled.
HSE testing of low-dust flour
The Health and Safety Executive (HSE) carried out independent dustiness testing of 2 low-dust wheat flours provided by British suppliers, which were processed using different methods. One has an oil ingredient added to make it less dusty, the other has gone through a hydro-thermal refining process where the finer flour particles are removed.
The laboratory testing allowed HSE to compare their dustiness against normal wheat flour that doesn’t contain additives.
The following photos show the dust levels generated during manual sieving. The amount of dust is highlighted using a strong light beam to show that using low-dust wheat flours significantly reduces the flour dust generated.
This process is also explained in HSE’s video of testing low-dust flour.
The reductions in flour dust exposures for sieving tasks were as much as 47-86% with the low-dust flours, compared with normal flour.
These next photos show dust levels generated when tipping flour into a container or filling a dredger for automated flour dusting. There was a reduction in flour dust exposures of 67-78% when tipping low dust flours compared with tipping normal flour.
How using low-dust flours will help you protect your workers
Using low dust flours will reduce airborne dust breathed in by bakers during their routine tasks of applying flour to work benches to mould dough and using sieves and dredgers. With less flour being wasted they may reduce flour usage, which means less clean-up time and effort.
Used in conjunction with careful handling techniques, low-dust flours may remove the need for wearing respiratory protective equipment (RPE) or using extraction.
These benefits will significantly help employers to comply with the law and help bakers stay healthy.
Find out more
HSE’s asthma website has a case study on how a bakery used low-dust flour to reduce asthma risk.
There is general guidance on health risks such as rhinitis and dermatitis in food industry occupational health risks.