About LPG

Liquefied Petroleum Gas (LPG or LP gas) is a fossil fuel used for heating appliances, cooking and vehicles. When used for vehicles it is often referred to as autogas. 

LPG remains a liquid under pressure (when contained in a cylinder/tank) and this pressure depends on the type of LPG  and temperature surrounding the cylinder. Once pressure is released the liquid will revert back to vapour. 

 

Around two thirds of LPG is extracted directly from the Earth. Some interesting facts below...

Safety: Please take care when using LPG, contact with the skin will cause burns. More information below about LPG and safety. 

Appearance: LPG as a liquid is colourless and as a vapour and cannot be seen.

Smell: LPG has no distinct smell so for safety reasons a stenching agent is added during production to give an unplesant smell to aid detection. 

Flammable: LPG is highly flammable when mixed with air. 

Vapourisation: 1 litre of liquid LPG will produce approximately 250 litres of flammable gas vapour.

Vapour Density: LPG vapour is heavier than air. Any escapes will find its way to the lowest level where it can remain and form a flammable mixture. Therefore LPG vessels must be sited away from drains and appliances must not be sited in basements or cellars. Cylinders in boats, motorhomes/caravans must be stored in purpose built sealed gas lockers with the appropriate venting for gas to escape in the event of a gas leak. 

Liquid Density: LPG is lighter than water and therefore floats on top of it in a similar way to oil and petrol. Care must be taken with LPG dropping into drains or basements.

Expansion: When LPG heats up it expands very rapidly. In order to allow for expansion LPG cylinders and tanks are only filled by volume to a maximum of 80% of the total volume of the retaining vessel.

Boiling Point: The boiling point is the temperature below which LPG will not vaporise to form a gas vapour.
The boiling point of Commercial Propane is approximately – 42oC.
The boiling point of Commercial Butane is approximately – 2oC.
Commercial Butane can be affected by cold weather resulting in poor pressure and should not be used outdoors in winter months. Commercial Propane is not adversely affected by cold weather in the UK and is an ideal fuel source for heating, cooking and industrial applications. 

Chemical Reaction: Ensure use of specific LPG hoses and replacement dates are adhered to. LPG is aggressive to non-metallic materials so it is important to use correct equipment . 

Toxic: Non-toxic but in very high concentrations LPG vapour acts as an anesthetic and subsequently an asphyxiate by diluting or decreasing the available oxygen.

Ventilation: Due to fuel/ air mix it is important that LPG appliances are serviced regularly and installed by a LPG engineer to ensure they burn efficiently with adequate ventilation. 

Commercial Propane = 23:1
Commercial Butane = 30:1

 

LPG Propane/Butane mixture

The below data can be used only as a guide on how the mix of LPG can differ per country. The mixture of propane/butane can also vary station to station.

Countries

LPG Grades

Reported Propane/Butane mixture

Austria

A

from 100%/0% to 80%/20%

Belgium

A

60%/40% all year

Czech Republic

A-C

60%/40% in winter,
40%/60% in summer

Denmark

A

70%/30% from 1/09 to 31/05

Finland

A

95%/5% from 1/09 to 31/05

France

A-C

grade A from 1/11 to 31/03,
grade C in summer

Germany

A-E

grade B from 01/12 to 31/03,
grade E in summer

Greece

D

20%/80% all year

Hungary

C

40%/60% all year

Ireland

A

98%/2% all year

Italy

A-C,
D-E

from 90%/10% to 20%/80% from 1/11 to 31/03,
grade D or E in summer

Poland

A-D

grade A from 1/11 to 31/03,
grade D in summer

Portugal

A

92%/8%

Slovenia

C

35%/65%

Spain

C

35%/65% from 1/11 to 31/03

Turkey

B

50%/50% from 1/11 to 31/03,
30%/70% in summer

United Kingdom

A

98%/2% all year

 

The LPG grades are defined by the temperature at which they reach the minimum pressure of 150 kPa.

 

Temperature

Possible Propane/Butane mixtures

grade A

-10°C

from 100%/0% to 60%/40%

grade B

-5°C

from 60%/40% to 40%/60%

grade C

0°C

from 40%/60% to 30%/70%

grade D

+10°C

from 30%/70% to 10%/90%

grade E

+20°C

from 10%/90% to 0%/100%

 

LPG or Autogas in the UK is predominately propane (same mixture of a red exchange propane gas bottle), which is usually a minimum of 90% propane. This will allow you appliances and heating to work in the same way as using a red propane bottle. 

Propane's boiling point  is -42 degrees celsius which is the important temperature for the users of the gas as your red propane gas cylinder will work more effectively in much colder weather compared to blue butane gas bottles. Knowing that you fill your refillable bottle mainly with propane in the UK your good to go down to around -30 to -35 celsius.

In Europe LPG/ autogas can vary in its mix (please see table above). They generally change the autogas depending on the time of year, so there is more propane in winter and less in summer.

Irrelevant of the mix your gas appliances will generally work OK as their is a blend/mix of both LPG gases.