Flammable liquids and gases

A flammable substance, is a substance that has a flash point below 55°C, and the flash point is the lowest temperature at which a small flame causes the vapour above the liquid to ignite under defined test conditions.

The classes of flammable liquids in South Africa

These are defined in the standard SABS 0400 Code of Practice for the Petroleum Industry. Flammable liquids are classified as follows:

• Class 1A : Liquids with a flash point below 23°C and a boiling point below 35°C
• Class 1B :Liquids with a flash point below 23°C and a boiling point above 35°C.
• Class 1C :Liquids with a flash point at or above 23°C but below 38°C
• Class 11 : Liquids with a flash point at or above 38°C but below 60.5°C
• Class 111A : Liquids with a flash point at or above 60.5°C but below 93°C
• Class 111B : Liquids with a flash point at or above 93°C

Storage areas for flammable liquids and gases

Flammable materials should not be stored along escape routes in a building. The storage area should :

• Have Non-combustible walls - made of brick or metal,

• Shelving, and packaging should be non-combustible,

• Be closed with a non-flammable door (metal) and should be kept locked,

• In a large store with a floor area of more than 10m² there must be a second door in the opposite walls as an additional escape door and should be able to be opened from the inside.

• A concrete floor should to retain the flammable liquids in the event of leakage.

• Have a bund or pan to contain the liquids to prevent the spread of burning flammable liquids,

• Ventilated to prevent vapour accumulation.
• Lighting of the flameproof type with enclosed wiring. Switches and other electrical equipment should be outside the storage area.
• Have a 9kg dry powder extinguisher mounted outside the store.
• Signs indicating "No Smoking" and "No Open Flames"
• People should not work in the store unless the doors are fully open and unobstructed.