Nearly every workplace has potentially dangerous liquids, including fuels, paint thinners, solvents, cleaners, waxes and adhesives, according to the Canadian Centre for Occupational Health & Safety.
Classifying liquids as either flammable or combustible depends on the liquid’s flashpoint. CCOHS states that a liquid’s flashpoint is based on the lowest temperature at which it gives off enough vapor to start burning at its surface. Flammable liquids have flashpoints lower than 100° F, whereas combustible liquids have flashpoints greater than 100° F but lower than 200° F.
A mixture of vapor and air must be ignited for a flammable or combustible liquid fire to start. According to CCOHS, common ignition sources include:
- Sparks from electrical equipment
- Sparks, arcs and hot surfaces resulting from welding operations
- Static electricity sparks
- Flames from portable torches and heating units
- Hot surfaces, including boilers, furnaces, steam pipes, electric lamps, irons, electric coils and hot bearings
- Embers from incinerators, fireboxes and furnaces
To avoid a fire, eliminate ignition sources. Do not smoke or operate spark-producing machinery near these liquids, and use only explosion-proof equipment in hazardous areas.
When working with flammable and combustible liquids, a well-ventilated workplace is crucial. CCOHS notes that a properly working ventilation system will be able to remove flammable vapors, reducing the chance of ignition.
Have an assessment performed by a qualified person to determine if your systems, including how you store, handle and dispose of flammable and combustible liquids, is adequate, CCOHS recommends.