What is liquefied petroleum gas (LPG)

LPG is short for liquefied petroleum gas and is the flammable hydrocarbon gases propane and butane. There are a number of fuel gases that fall under the LPG products label, including propane, butane and isobutane, as well as mixtures of these gases.

LPG gas is colourless and odourless until an odourant is added for safety reasons. When compressed, LPG takes a liquid form. When released in a controlled manner and burnt it has a high energy content. LPG can be conveniently stored and transported and is an excellent fuel for heating, cooking, and many other applications.

What is LPG made up of?

Liquefied petroleum gas (LPG) is made up of carbon and hydrogen atoms forming propane and butane. Flammable hydrocarbon gases (LPG) are liquefied through pressurisation and commonly used as fuel. LPG is stored in vessels ranging from small gas bottles to larger gas cylinders and tanks used at home or industrial premises.

When used in vehicles for propulsion LPG is generally called Autogas.
In small portable cylinders, LPG is sometimes referred to as BBQ gas, Patio gas or camping gas.
Isobutane is the other common LPG gas, used as a refrigerant in ground source heat pumps, fridges, freezers and for various manufacturing processes.
Isobutane is usually sold in cylinders for use in campervans, caravans and motorhomes.

Where Does LPG Come From?

LPG components are found naturally in combination with other hydrocarbons and fossil fuels, typically crude oil and natural gas. LPG is produced during natural gas processing and oil refining. When isolated, LPG can be liquefied through pressurisation and stored in gas cylinders or gas tanks.

Refining LPG from oil wells

A gas/oil mixture is piped out of oil wells and into a gas trap, which separates the stream into crude oil and ‘wet’ gas, which contains LPG and liquefied natural gas. The heavier crude oil sinks to the bottom of the trap and is then pumped into an oil storage tank and transported to refineries. LPG is one of the refined products derived from crude oil distillation.

How LPG is used

LPG is used for cooking, heating, hot water, autogas, aerosol propellant, air conditioning refrigerant and backup generator applications. LPG for home use is typically supplied in large cylinders or supplied via tanker lorry to an on-site gas tank.

LPG has many additional uses for caravans, motorhomes, boats, camping and even hot air balloons. Business, industrial and agricultural uses for LPG include processes such as kilns, ovens, steam boilers and LPG-powered powered forklifts.

LPG vaporisation

LPG liquid turns back into gas vapour at boiling point when you release some of the pressure in the gas bottle by turning on your gas appliance. Vaporisation also makes the gas bottle feel colder than the ambient temperature and even colder the more gas you are using. The LPG gas vapour is held at the top of the bottle and the liquid LPG is at the bottom.

The level of fill in the gas cylinder decreases as LPG is being used, as this affects the rate of vaporisation. As the liquid level falls in the cylinder, the surface area in contact with the cylinder walls is reduced. This results in a reduction of latent heat available, so the rate of vaporisation decreases. The off-take rate of any cylinder or bulk tank slowly decreases as the liquid level falls, until eventually the liquid is completely vapourised, and the vapour pressure is reduced to below the regulator working pressure.

LPG Gas chemical formula

The LPG (propane) chemical formula is C3H8. Butane and Isobutane both have the same chemical formula, C4H10, as isobutane is an isomer of butane.

Eco-friendly clean burning LPG

LPG is an eco-friendly energy choice, as it is a low-carbon, low-sulphur fuel. LPG components result in lower carbon dioxide (CO2) emissions than other energy sources. LPG can help lower greenhouse emissions during the transition to renewable energy sources.

There are many places across the UK and Europe where you can fill up with LPG. Click here for more information

Refilling is quick and easy.
Click here to download a simple PDF fact sheet on how to refuel your gas tanks or refillable bottles

All of our LPG systems can be taken on the Eurotunnel as they have a simple isolation valve that can be operated to turn off the supply before boarding.

2.5.1 The Carriage of gas containers must be declared to Eurotunnel by the Customer.  All gas containers carried on passenger Shuttles will be checked by LeShuttle;

2.5.2 Cylinders and tanks, and appliances powered by gas must be switched off or disabled during Carriage;

2.5.3 Leaking or inadequately secured cylinders, tanks or appliances will not be accepted for Carriage;

2.5.4 Empty or part empty cylinders will be considered to be full unless they have been purged (cleaned). There is no restriction on the number of empty and cleaned cylindersthat may be carried.  To be accepted for Carriage the Customer must produce a cleaning certificate;

2.5.5 Flammable gas containers, cylinders and appliances containing LPG, LNG, CNG or BP Gas Light, or any other flammable gas must be declared by the Customer;

2.5.6 The maximum permitted volume and quantity of flammable gas cylinders and tanks per Vehicle is:

• For portable containers (cylinders/bottles, etc): Maximum of 47kg per cylinder and no more than 50kg per Vehicle if more than 1 container;
• For fixed containers (tanks): Maximum of 47kg per container and no more than 50kg per Vehicle if more than 1 container;
• Fixed containers must be no more than 80% full. The capacity of the container will be checked by LeShuttle staff.Portable gas containers (cylinders/bottles, etc.)

  Portable Gas Cylinders

  For the purposes of this text, this means cylinders/bottles containing flammable gas that can be moved from the vehicle for replacement or re-filling. The quantity of gas is limited to 47kg (or approximately 93 litres) maximum for a single container and to 50kg (or approximately 99 litres) maximum in the case of several containers.

  Fixed Gas Containers i.e Tanks

  For the purposes of this text, this means fixed containers that are permanently installed or fixed in a vehicle and are refillable from outside the vehicle.

  The quantity of gas is limited to 47kg (or approximately 93 litres) maximum for a single container and to 50kg (or approximately 99 litres) maximum in the case of several containers. Each container must be no more than 80% full.

  The quantity will be checked via the gauge or remote indicator but if neither are present, the vehicle will be refused.

   

  All information provided is from the LeShuttle website and correct as of August 2023. We Provide no responsibility for the information obtained from their website.

LPG Adaptors

ACME thread Adaptor

Also known as: ACME thread, ACME adapter or ACME nozzle
This connector has a thread fitting onto which the petrol pump is screwed before the trigger is pulled to establish a seal before fuel transfer.
For use in the following countries:
Australia, Austria, Belgium, Chile, Germany, Ireland, Liechtenstein, Luxembourg, Switzerland, United Kingdom, United States of America.

EURO Adaptor

Also known as: Euro nozzle
The Euroconnector has been introduced in Spain with great success and is currently being introduced in the U.S. replacing dish and ACME connections.
For use in the following countries:
Portugal & Spain

DISH Adaptor

Also known as: Italian adapter, DISH coupling, Italian dish, Dish adapter, French Adapter

For use in the following countries:

Albania, Algeria, Austria, Belarus, Bosnia, Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, France, Greece, Hungary, India, Italy, Kosovo, Latvia, Lithuania, Macedonia, Malta, Moldova, Montenegro, Norway, Poland, Portugal, Romania, Russia, San Marino, Serbia, Slovakia, Slovenia, Sweden, Switzerland, Turkey, Ukraine.

The information contained in this document is intended to give guidance and believed to be accurate and represent good practice at the time of publication. No responsibility or liability is accepted for any loss or damage arising out of the information given. It is important that all users adhere to all legal requirements, regulations, CoP`s and standards, particularly, those relating to Gas safety including the country you are visiting.

PROPANE/BUTANE LPG MIXES IN EUROPE

The table shown below contains a list of countries and most common propane/butane mixtures for that country. Mixtures may vary between fuel stations.

Why is this information important???? An example would be if you filled up with LPG in the summer months which would possibly have a high Butane content, in the colder months in the UK you would not be able to use the gas you have filled up with as it will not gas off due to low temperature!

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

When filling with LPG at a filling station using the Dish type fill adaptor, you may find that when the pump head is locked into the adapter, it leaks LPG from around the adapter and pump head connection.

This is NOT caused by a faulty Fill Adapter, or the adapter is egg shaped as stated on some forums! But a worn rubber gasket in the pump head itself (thats the bit you hold that attaches to your vehicle which is connected to to the dispenser by a thick black filler hose). This is quite a common fault especially in France usually in the summer months. 

Our suggestion is to find an alternative garage to dispense gas from, mainly for safety reasons as you must not adapt the filler dispenser on the garage forecourt.

When changing gas cylinders over it is always a good idea to use a leak detection fluid to make sure you have a gas tight connection. After you have changed the cylinders over, turn the gas on and spray or brush a leak detection fluid over the joints form cylinder to regulator, you should wait 30 seconds whilst watching for bubbles to increase in size. If no bubbles are detected you have a good joint, should you find bubbles forming then turn the gas cylinder off and remake the joint. Also, if you are using a cylinder regulator hose connection that has a rubber seal, ensure that it is intact and in good condition.

Always use a Leak detection spray that is designed for the job to the correct standard EN 14291:2004

If you find that you are in need of leak detection fluid but cannot obtain any due to your location, DO NOT USE diluted washing up liquid! Washing up liquid is a corrosive fluid and will damage brass fittings and valves within a short period of time.
In an emergency case you can use diluted hand soap as a leak detection fluid, again this is not the correct solution but will help you get by to find your leak. After using wash the area with clean water and dry off.

If you cannot find a leak but can still smell gas, turn the gas cylinder or tank off and have the installation inspected by a qualified engineer before re-using.

Put some Leak detector fluid or soapy water made with liquid hand soap in a spray bottle or a dish.

Turn on the gas bottle without turning on any appliances.  This pressurises the system.

Next, spray the entire valve, regulator and hose assembly with the leak detector fluid or soapy water solution.

Alternatively, you can apply the soapy water with a paint brush, basting brush or it can even be sponged on.

Bubbles will form if there is a gas leak, and you may also smell the gas.

You need to test the entire assembly from the gas bottle valve all the way to where the gas hose attaches to the regulator.

When done, rinse with clean water to remove the leak detector fluid or soap solution.

Remember to test with Leak detector spray or soapy water solution every time you re-connect your gas bottle.

If you find a leak, turn off the gas bottle immediately!

Do not turn the gas cylinder or underslung tank on or attempt to use any appliances until the problem is rectified.

Do Not Use washing up liquid solution to find leaks, it is corrosive and will damage valves hoses.

A pressure relief valve is the single most critical safety feature on an LPG cylinder or underslung tank. It is incorporated within the main valve fitting on a cylinder or a separate valve on an underslung tank, usually covered with a red cap.

A Pressure relief valve is designed to relieve excess gas pressure in the cylinder or underslung gas tank that might result from overfilling or exposure to excessive heat or fire.

The function of a pressure relief valve is to keep a cylinder or tank from rupturing in the unlikely event of excessive pressure build-up.

The pressure relief valves are held in the closed position by the force of a powerful spring inside, and as long as the pressure remains below a certain level the valve will stay closed.
The normal opening pressure of a release valve is Between 26 & 27 Bar in pressure.

What happens when the valve operates?

Having the pressure relief valve releasing gas is a rare event. In normal operation you should never experience venting. If the pressure rises beyond the force of the spring, the valve will open to vent the excess pressure. If this happens, you may hear a hissing sound and see cold gas vapour being released, also the smell of gas. Once sufficient pressure is released, the valve closes.

If this ever happens, just stay clear of the area and let the gas dissipate. Do not use your mobile phone, any electrical devices or other ignition sources near a venting gas cylinder or tank.

If this happens contact a certified gas engineer who is conversant with gas tanks and cylinders and advise them of the release.

LPG, Propane & Butane when produced are clear and have no smell, making them difficult to detect in the event of a leak! So before the gas is loaded into tankers Ethyl Mercaptan is added which is commonly referred to as a stench agent, this helps detect gas in the event of a leak. The smell is very destinctive and is often described as being like rotten cabbage or eggs.

Ethyl mercaptan in propane is also known as Ethanethiol. It is a sulfur compound with the chemical formula CH₃CH₂SH that is a clear liquid with a very strong and distinctive odour.

The Ethyl Mercaptan odourant is slightly less volatile than the LPG/Propane in which it is dissolved. As the LPG/Propane vapour is used by the appliance, the odourant is also removed in the process. Due to its lower volatility, there is a slightly higher concentration of odourant as the last of the Propane liquid is converted to vapour and used.

The odourant is noticeable at very low concentrations by its use, so this small increase in concentration can be very apparent and you may smell more of the stench agent when the cylinder is about to run out.

If you can smell gas, turn the gas cylinder or tank off and have the installation inspected by a qualified engineer before re-using.

The calorific value of LPG can be worked out using the following calculations:

• 1 Litre of propane = 7.08 kWh (kilowatt hours) or 24000 BTU/h
• 1kg of propane = 14.019 kWh (kilowatt hours) or 47300 BTU/h

To convert from m³ or ft³ into litres use the following calculations:

• To convert m³ of vapour to litres of liquid; multiply by 3.85
• To convert ft³ of vapour to litres; multiply by 0.1034

1kg of LPG = 1.969 litres

So a 6kg propane cylinder would carry 11.814 litres. At 15 degrees C

A POL gas fitting (POL fitting) is an LPG gas connection fitting typically used on LPG (propane) gas cylinders. POL fittings can be found on larger size gas bottles used on static caravans. POL is the acronym for the company that first made the valve fittings – Prest-O-Lite.

The female POL gas bottle fitting (POL fitting) is incorporated into a POL valve fitting on the LPG-propane cylinder, utilising a left-handed or reverse thread. The male POL gas fitting is used on pigtail hoses, gas regulators and other hose style connectors.

Alugas are the only lightweight all alloy refillable LPG upright cylinders, that are fixed in place and are designed for the leisure market.
Click here to download our PDF Alugas Information Sheet

Underslung or underfloor LPG gas tanks are available in a range of sizes from 8kg up to 46kg. The underslung tank or "Caratank" is a unique bulk underfloor LPG tank suited ideally to motorhome users and catering trailers alike.
Click here to download our PDF Caratank Information Sheet.

If you are wondering if a particular LPG refillable cylinder will fit in your locker or what its weight is? Click the link below to view or download our PDF comparison sheet. CLICK HERE

You must not fill an LPG tank or cylinder system with CNG due to the very high storage pressures typically 206 – 248 Bar (3000-3600Psi). Compare that to a standard LPG tank or cylinder, rental type or refillable and you will have an average cylinder pressure of approximately 7 Bar with a maximum permitted pressure of 26 Bar.
No Adaptors must be used, or changes to the cylinder to accept CNG!!!

The simple answer is yes you do need ventilation in a locker containing gas cylinders!

Gas locker accessible from the outside of the vehicle and cannot be accessed from within the habitable area:

Permanent ventilation of any LPG cylinder compartment shall be provided to the exterior of the vehicle through the floor. If the ventilation is provided at low level, the free area shall be at least 2 % of the compartment floor area with a minimum of 10 000 mm2.

It shall not be possible for any part of the ventilation area to be obstructed by an LPG cylinder.

Gas locker accessible from the inside of the vehicle:

The access from the habitable area to the LPG cylinder compartment is only provided via a sealed door or hatch. The height of the bottom edge of the door opening is at least 50 mm, measured from the bottom of the LPG cylinder compartment.

The compartment can contain a maximum of two cylinders, each having a capacity of not more than

11 kg, if the ventilation requirements are met at 2% or 10000 mm2 of the locker floor area. As described for an external locker. A vehicle exhaust is more than 300 mm from the locker floor and only Extra low voltage is allowed for gas controls.

A locker can contain two cylinders with a combined capacity of 7kg, the ventilation can be reduced via one vent if the vent has a minimum internal diameter of 20mm. Low level only and must fall below the vehicle floor.

If there is a fire, please call 999 immediately and inform the operator that it is an LPG fire.

In a gas emergency, act as quickly as possible and take the following safety steps;

Internal gas leak:

LPG is heavier than air, so it’s essential to open all doors and windows to ventilate the property.

If your property has a basement or cellar, open all doors and windows and leave the property.

Internal and external gas leaks:

Do not turn on/off any electrical switches.

Extinguish all naked flames, do not smoke, strike matches or do anything which could cause ignition.

If there are any electrical security entry phones/locks, please open doors manually.

If you are unsure call the emergency services!!!