HSE Guidelines to Safe Storage of LPG Cylinders
Liquefied Petroleum Gas (LPG) includes commercial butane, commercial propane and mixtures thereof as defined in British Standard BS:4250.
In general, the precautions to be taken in handling LPG are similar to those applying to petroleum spirit but in particular, all persons concerned with the handling of LPG should be familiar with the following properties.
- LPG is normally stored as a liquid under pressure.
- Leakage, especially of liquid, may release large volumes of flammable gases.
- A very small proportion of LPG released into air can give rise to an explosive mixture.
- LPG vapour is heavier than air and may flow along the ground or through drains and be ignited at a considerable distance from the source of leakage. In still air, any vapour will disperse slowly.
- LPG liquid, by its rapid vaporisation and consequent lowering of the temperature, can cause severe frost burns if it comes into contact with the skin.
- For general purposes, LPG is odorised before distribution so that its distinctive smell can give warning of a gas escape.
General Storage Information
- It is preferable that all LPG is stored in the open air but where this is not practicable, particularly for cartridges (small disposable containers), the quantities stored within the buildings should be restricted to those shown in Table 1 below.
- Access to all storage places by unauthorised persons should be prevented and such places should be marked with notices prohibiting smoking and the use of naked flames.
- Refillable LPG cylinders are considered to be full whatever the state of their contents.
- LPG should not be stored in the vicinity of cylinders containing other gases or hazardous substances without specialist advice.
- The position chosen for storage should always be level and concreted, paved or compacted to provide a load-bearing surface. Outdoor storage areas should be slightly graded for drainage of surface water.
- LPG should NEVER be stored below ground level in cellars or basements.
- There should be no openings into buildings, cellars or pits within 2m of an LPG storage area or the separation distance given in Table 1, whichever is greater. If there is an unavoidable opening within 2m, the opening should be securely covered and fitted with a suitable water seal to prevent the entry of vapour.
- The storage area should be kept free from weeds, long grass and accumulations of readily combustible material at all times.
- Cylinder stacks and cylinder areas situated outdoors are unzoned provided they comply with the requirements contained within this leaflet and are now not classified as hazardous places under DSEAR whereas previously they were zone 2.
Storage of Cylinders on Vehicles or Trailers
- No cylinder of LPG Gas shall be stored in an enclosed vehicle other than a cylinder which is specifically designed to keep fuel for the motive power of the vehicle. Such cylinders should not be included in storage quantities.
- Cylinders kept on a vehicle or a trailer should be treated as a single stack and the appropriate separation distance should be applied.
- For the carriage of cylinders in closed vans see UKLPG Code of Practice No. 27.
Storage of Empty Cylinders
- For the purpose of defining separation distances, all LPG Gas cylinders are to be considered as full whatever the state of their contents.
- Nominally empty cylinders should be segregated from full ones and an appropriate indication made so that they can be readily distinguished from each other.
- Cylinders should be inspected regularly for leakage.
- Never attempt to find a leak by means of a naked flame.
- Leaks can be detected by :-
- Sense of smell
- The sound of escaping gas
- By condensation or frosting round the leak
- Leaks may be confirmed by brushing soapy water over the suspected leak source.
- The provision of automatic flammable gas detection equipment should be considered for enclosed storage locations.
It is recommended that the fire authority should be consulted in case of all storage in excess of 1000 kg regarding fire fighting equipment, water supplies, means of access for fire fighting appliances, protection of fire fighting personnel and arrangements generally to ensure an early call to the Fire Brigade in the event of a
fire breaking out.
Fire extinguishers should be and should be selected installed and maintained to BS 5306 Part 3. Dry Powder fire extinguishers should have a rating of at least 223B and comply with BSEN 3. The dry powder extinguisher(s), should be located in easily visible positions near exits, at perimeter of the store and in safe positions on access routes between stacks. Under 400kg of LPG requires 1 x 9kg Dry Powder Extinguisher. Over 400kg of LPG requires 2 x 9kg Dry Powder Extinguishers plus 1 per additional 10,000kg in excess of 5,000kg (e.g. 25,000 kg = 4).
|Types of Building
Shops or Offices
|Maximum quantity of LPG cylinders or cartridges||Remarks|
|(a) With residential accommodation||15kg||Unless 60 minutes fire resisting separation is provided between the two occupancies with no direct access between, when up to 70kg may be stored.|
|(b) Without residential accommodation||70kg||Not more than 5 cylinders or 20 if the maximum capacity is 3kg. No cylinder must exceed 20kg capacity.|
|(c) Demonstration area (outside designated area)||50kg||Not more than 4 cylinders and 6 cartridges|
Emergency Contact Numbers:
Code of Guidance for the Storage of LPG: