Storing Petroleum

Merseyside Fire and Rescue Authority is the Petroleum Licensing Authority and therefore has responsibility for the enforcement of petroleum regulations at petrol filling sites across Merseyside.

Petrol is a highly flammable liquid and designated as a dangerous substance. At room temperature its vapours are heavier than air.

Petrol vapour when mixed with air can form an explosive atmosphere at very low concentrations; and has a Flammability range of 1.3% – 7.1%

The Lower Explosive Limit (LEL) is a concentration of 1.3%.

That is to say; where petrol vapours amount to 1.3% concentration in an atmosphere and an ignition source is present, an explosion will occur. Where the concentration is less than 1.3% the mixture is described as ‘too lean’ and even if an ignition source is present, the vapours will not ignite.

The Upper Explosive Limit (UEL) is a concentration of 7.1%

That is to say; where petrol vapours amount to upto 7.1% concentration in an atmosphere and an ignition source is present, an explosion will occur. Where the concentration is greater than 7.1% the mixture is described as ‘too rich’ and even if an ignition source is present, the vapours will not ignite.

The storage of petrol other than at licensed sites should therefore be kept to an absolute minimum and should never be stored in a house or living accommodation.

Domestic Storage

Legislation dictates that where petrol is stored for domestic purposes then storage must be in approved containers that are appropriately labelled and stopped and that the total amount stored should not exceed two 5 litre plastic containers or 10 litre metal containers. The total amount stored should not exceed 20 litres in total. It is important that even small amounts of petrol are stored safely and securely in a well ventilated area away from heat and ignition sources.