LPG...

LPG is an abbreviation for "Liquid Petroleum Gas". LPG can be delivered in lorries to areas and/or homes that can't have a mains gas supply, e.g. mobile homes, boats caravans and houses in remote areas. The most famous brand name is Calor Gas. There are several competing suppliers but Calor are still the best known. 

There are two LPG gases, propane and butane. (Mains gas is methane and generally termed 'natural gas'.) Propane is the most popular as butane stops working at storage temperatures below about 0 degrees C, as the liquid gas needs to be above -1 degrees C to make it change from liquid into vapour. (Propane will do this at storage temperatures down to -45 degrees C.)

There are two ways to use/store LPG. In portable steel 'bottles' or in a fixed, larger capacity storage tank. 

LPG differs from mains gas in several important ways. it has different combustion characteristics from natural gas so LPG appliances have to be set up differently. Most appliances can be converted to run on LPG by changing the gas jets and/or burner assemblies. Some appliances are designed for only one type of gas or the other. There is a data plate on all gas appliances stating the type of gas they are set up to use. Some modern boilers can be adjusted from one type to the other purely in the electronics software. 

While natural gas is lighter than air, LPG is heavier. This is more significant than first appears as while natural gas escaping from a leak tends to disperse into the atmosphere, LPG tends to flow down to the floor and form pools of gas unnoticed. For this reason it is illegal to install LPG appliances in cellars or below ground level, or to fit storage cylinders close to drain openings.

This also means a gas leak in a boat is particularly dangerous as the gas flows downwards and accumulates in the space under the floor, below water level. In a caravan a drain hole through the floor can be provided to allow any leaked gas to escape but not in a boat!

The additional regulations governing installation of LPG storage, pipework and appliances means there are separate qualifications for installers of LPG in houses, caravans, park homes and boats. If you need an LPG appliance installed or serviced, check with Gas Safe Register that your installer holds the correct LPG qualification for your type of installation.

I am qualified to work on LPG appliances in houses, park homes and boats. (Bear in mind I'm a boiler fault tracing specialist not an installer though!)