Combustible Dust FAQ

What counts as combustible dust?

Any fine solid particulate that can burn when suspended in air. In Ontario facilities that usually means wood, flour, grain, sugar, starch, milk powder, aluminium, magnesium, steel fines, polymer powders or rubber crumb. Materials that are inert in bulk can still be hazardous as fines.

How much accumulation is too much?

Less than you would expect. A thin layer across a large area of overhead steel adds up to a substantial quantity of fuel once it is disturbed all at once. What matters is total accumulation across the building, not depth at any one point.

Why does overhead dust matter more than floor dust?

Because that is where nobody is looking. Floor-level housekeeping deals with what people can see. The layers on rafters, beams, ductwork and cable trays sit undisturbed for years, and they are the fuel for a secondary explosion if a smaller event shakes them loose.

How often should we clean overhead surfaces?

It depends on how fast your process generates dust. Food production, bakeries and manufacturing plants are often quarterly. Warehouses are typically every six to twelve months. The reliable way to set a schedule is to measure actual accumulation at your site rather than guess.

Is overhead cleaning a legal requirement in Ontario?

Ontario employers have a general duty to identify and control workplace hazards, and fire code requirements apply to accumulation of combustible materials. Insurers and food safety auditors increasingly ask for evidence of overhead cleaning. We are a cleaning contractor rather than a compliance authority, so for a formal determination you should consult a qualified fire protection professional.

Can we just blow the dust down with compressed air?

No. Compressed air takes settled dust and puts it into the air, which creates the dispersion a dust explosion requires. Brushing it down does the same thing more slowly. HEPA-filtered vacuum extraction captures the dust instead.

Can we keep operating while you clean?

Usually yes. Most of our work happens around operating hours, overnight or at weekends. Whether a specific area can stay in use during cleaning depends on the material and the access method, and we establish that at the site assessment.

What documentation do we get afterwards?

Before-and-after imagery captured on camera from the pole head, showing the surfaces that were cleaned. That is what you hand to an auditor, an inspector or an insurer.