Page 356 - IGC BOOK

Storage of Flammable Liquids

Many work activities require a limited quantity of flammable liquids to be held in the workplace, and
these may be stored in suitable cabinets or bins of fire-resisting construction that are designed to
retain spills.

Definitions
Combustible: A liquid with a flash point over 100°F (38°C) is considered combustible.

• Examples: diesel fuel, motor oil.
• Hazard: May produce ignitable vapors at elevated temperatures.

Flammable: A liquid with a flash point under 100°F is considered flammable.

• Examples: gasoline, acetone, toluene, diethyl ether, alcohols.
• Hazard: May produce ignitable vapors at normal ambient temperatures.

FLASH POINT

The flash point of a liquid is the lowest temperature at which flammable vapour will form at the
surface that can be ignited by the application of an external ignition source. Sustained combustion
does not continue (the vapour burns briefly and then goes out).

The lower the flash point, the lower the temperature at which it is possible to ignite the liquid.

Some of these liquids have very low flash points and so are labeled as ‘highly flammable’ or
‘extremely flammable’:

• Category 3 ‘flammable liquids’ have a relatively low flash point (between 23°C and 60°C).
• Category 2 ‘highly flammable liquids’ have a low flash point (<23°C) and boiling point >35°C.
• Category 1 ‘extremely flammable liquids’ have a low flash point (<23°C) and boiling point <35°C.

Employers should determine the extent of the flammable atmosphere that could result from leaks
and ensure all potential ignition sources are excluded.

Cabinets and bins storing flammable substances should be located in well-ventilated areas that are:

• Away from the immediate processing area where possible; and
• Do not jeopardize the means of escape from the area.

Flammable liquids should be stored separately from other dangerous substances that may increase
the risk of fire or compromise the integrity of the container, such as oxidisers.

The recommended maximum quantities that may be stored in cabinets and bins are:

ENSIGN | Unit IG2 – Element 10 –Fire 11