Housekeeping is a named control measure under the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) for any site where combustible dust builds up — because an accumulated layer disturbed into a cloud, in the presence of an ignition source, is how dust explosions happen. HSE guidance identifies flour, custard powder, instant coffee, sugar, dried milk, potato powder and soup powder among the combustible dusts requiring this control, and gives specific housekeeping methods to reduce the risk.
What does DSEAR actually require?
DSEAR implements the requirements of the EU 'ATEX 137' workplace directive in Great Britain. Employers must find out what dangerous substances are present and what the risks are, classify areas where an explosive atmosphere may occur into hazardous zones and control ignition sources within them, put control measures in place to eliminate or reduce the risk, and prepare emergency plans and training for staff who work with the substances.
Equipment used inside a classified zone is separately covered by the 2016 Equipment and Protective Systems (EPS) Regulations, which implement the equipment-focused 'ATEX 114' directive — a different regulation to DSEAR, covering the kit rather than the workplace.
Which dusts does this apply to?
HSE's own guidance for the food industry names flour, custard powder, instant coffee, sugar, dried milk, potato powder and soup powder as combustible dusts capable of forming an explosible cloud. The same principle extends to wood dust, some plastics and metal powders, and other fine, combustible particulate generated by an industrial process — any site producing this kind of dust needs a DSEAR assessment, not just food manufacturers.
What housekeeping does HSE guidance actually specify?
HSE's guidance is specific rather than general: maintain scrupulous cleanliness using a fully-earthed, centralised piped vacuum cleaning system, and avoid sweeping brushes and compressed air for anything other than genuinely non-dusty cleaning tasks — both can lift a settled layer straight back into an explosible cloud rather than removing it.
High-level horizontal surfaces where dust can silently accumulate — the tops of plant, ductwork, beams and racking — should be eliminated or sloped where possible, and where they cannot be, they need to be on a documented cleaning schedule rather than left until they are visibly coated.
Why does the concentration of a dust cloud matter?
HSE guidance notes that dangerous dust concentrations sit in a range of roughly 75 to over 1,000 grams per cubic metre of air — a cloud dense enough that an observer struggles to make out solid shapes at 60 centimetres. That is a genuinely thick cloud, but a comparatively small, disturbed accumulation of fine dust is enough to reach it, which is why routine, correctly-chosen housekeeping matters more than an occasional deep clean.