» What is propane?
Propane is predominantly stored in red Calor LPG cylinders / bottles and bulk storage tanks. Like butane, propane is an LPG (Liquefied Petroleum Gas), existing as a vapour (gas) at ambient temperature and pressure conditions, yet easily liquefied by cooling or applying moderate pressure.
Propane, a saturated hydrocarbon gas with the chemical formula C3H8, belongs to the Alkanes (previously known as Paraffins) family of hydrocarbon gases.
» Boiling Point
A far lower boiling point than butane makes propane the more appropriate Calor LPG for outdoor use during colder months, and can be used all year round.
» Commercial Propane
Commercial propane, the form generally supplied in the UK, consists of propane along with concentrations of other hydrocarbon gases, such as propene and butanes.
The specification of commercial propane is defined in BS 4250, the British Standard ‘Specification for commercial butane and commercial propane’.
» Volume
The ability to liquefy under modest pressure distinguishes propane from natural gas.
An approximate expansion ratio of 274:1 means one volume of liquid propane produces 274 volumes of gas vapour. This greatly reduced volume is easily stored and transported in specially constructed pressure vessels (e.g. Calor LPG cylinders).
» Density
Propane vapour is 1.55 times denser than air, meaning it sinks to a low level when released in the atmosphere.
For this reason, propane cylinders cannot be stored below ground or near drains or cellar openings. Propane-fuelled appliances must not be installed within cellars or basements.
» Flammability
Propane mixed with correct proportions of air produces a highly flammable mixture, with a flammability range of between 2% and 10%, by volume of gas in air. Outside this range the mixture is either too lean or rich to propagate a flame.
» Calorific Value
The Calorific Value (CV) of a fuel mixture is the amount of energy released when a known fuel quantity undergoes combustion.
Propane has a CV of 95.8MJ/m3 whereas natural gas has a CV of 38MJ/m3, giving it a far greater heat energy release per unit volume, as well as a difference in air requirement and other combustion characteristics.
This means propane-fuelled appliances must have adequate means of ventilation, to ensure complete fuel combustion.
Regular servicing by suitably qualified individuals will ensure these requirements are met and appliances perform correctly and safely.
» Volatility
Propane is more volatile than butane. A boiling point of approximately -42.1ºC and a vapour pressure of around 7 bar / 100 psi (at 15ºC), means it is not adversely affected by the UK’s colder weather. This makes propane the ideal choice for heating, cooking and industrial applications.
» Odour
Propane is a colourless and odourless gas. For safety reasons a stenching agent of mercaptans (mainly ethyl mercaptan) and organic sulphides is added to propane, to ensure any leakage is easily detected by the distinctive and unpleasant smell.
» Your Gas Needs
If you are unsure which Calor LPG cylinder / bottles to use, please consult our simple guide to selecting the right one.
Persons involved in the storage and handling of propane cylinders should have adequate information, training and supervision.
