LPG FAQ

Liquefied Petroleum Gas

LPG is Liquefied Petroleum Gas. It consists of hydrocarbons Propane and Butane or a mixture of the two. LPG is a byproduct of both natural gas processing and oil refining. It's stored and transported as a liquid but turns into gas when released. This happens due to pressure and temperature changes.

Propane must be distributed in steel cylinders that can withstand high pressure while Butane and Propane mixes can be distributed in aluminium cartridges.

1. Make sure to read the Safety Data Sheets and safety information on the cylinder / cartridge itself.

2. LPG in its natural stage is odorless, however when stored and transported in cartridges / cylinders, an odor is inserted. In case of a leak, you will be able to smell the odor.

3. Store and transport the cartridge / cylinder in an upright position. During storage, make sure it's well ventilated.

4. When you are done working, always make sure to shut off the valve of your torch and disconnect it from your gas cartridge / cylinder for maximum safety.

4. If you are operating a business (for example a workshop) and have many cartridges / cylinders, follow your local regulations regarding signage and storing of dangerous goods. This is important in case of a fire / accident. The fire services will be able to identify which type of gas is stored and will proceed accordingly.

The main difference between a cartridge and a cylinder is the gas mixture, material and pressure.

A cartridge is made out aluminium and contains a mix of propane and butane and is pressurized up to 12,5 bar (181 PSI) at 50° Celsius (122° Fahrenheit).

A cylinder is made out of steel and contains pure propane or propene and is pressurized up to 27 bar (391 PSI) at 50° Celsius (122° Fahrenheit).

Propane, propene, and butane are all hydrocarbon gases, but they have distinct chemical structures and properties:

Propane (C3H8)

Propane is an alkane with three carbon atoms and eight hydrogen atoms. Its chemical formula is C3H8. Propane has the following characteristics:

  • Boiling point of -42° Celsius (-43,6° Fahrenheit), making it suitable for use in cold climates.
  • Easily liquefied under pressure, allowing for convenient storage and transport.

Propene (C3H6)

Propene, also known as propylene, is an alkene with three carbon atoms and six hydrogen atoms. Its chemical formula is C3H6. Propene differs from propane in that it has a double bond between two of its carbon atoms.

Butane (C4H10)

Butane is an alkane with four carbon atoms and ten hydrogen atoms. Butane has the following properties:

  • Boiling point between -1° Celsius (30° Fahrenheit) to 1° Celsius (34° Fahrenheit) higher than propane.
  • Easily liquefied and vaporized at room temperature.

Key Differences

  1. Chemical structure: Propane has three carbon atoms, propene has three carbon atoms with a double bond, and butane has four carbon atoms
  2. Boiling point: Propane has a lower boiling point -42° Celsius (-43,6° Fahrenheit) compared to butane -1° Celsius (30° Fahrenheit), making propane more suitable for colder climates.
  3. Applications: While both propane and butane are used as fuels, propane is more commonly used for outdoor and cold-weather applications, whereas butane is often used in portable devices and as a propellant.
  4. Energy content: Butane has a higher energy content per unit volume compared to propane, but propane is more efficient in combustion.

These differences in chemical structure and properties make each gas suitable for specific applications in various industries and everyday use.

Disposable Gas Cartridges / Cylinders are one time use meaning that once they are consumed you can no longer use them or refill them. It's in fact illegal to try and refill them because they are not designed for it.

Refillable Gas Cylinders are designed to be refilled. Depending on the country, check your local regulations if you are allowed to do it yourself or use a professional gas filling provider.

This varies from different countries and the type of gas cartridge / cylinder.  Check with your local municipal to act accordingly.

It depends on your application, weather conditions and the type of torch handle / burner and regulator connection.

For regular weather conditions in combination with blowtorches:

Powergas - EU 7/16" valve. This is a Propane / Butane mix and suitable for general heating applications such as soldering.

Ultragas - EU 7/16" valve. This is also a mixture a Propane / Butane mixture for general heating applications such as soldering. However, the Ultragas has a built-in sponge that allows the torch to be used upside down with no flare-ups in case you are in tight spaces and can't use the torch in it's upright position. Read the instruction manual of your hand-held torch for more information.

For cold weather conditions in combination with blowtorches:

Propane - UNEF 1" valve. This contains pure Propane and operates at a higher pressure meaning it's suitable for demanding applications like brazing. Propane  allows the torch to be used upside down with no flare-ups in case you are in tight spaces and can't use the torch in it's upright position and has a lower ignition point so it can be used during colder weather.

MAPP - UNEF 1" valve. This contains pure Propene and operates at a higher pressure meaning it's suitable for demanding applications like brazing. Propene  allows the torch to be used upside down with no flare-ups in case you are in tight spaces and can't use the torch in it's upright position and has a lower ignition point so it can be used during colder weather. Propene is more effective at reaching it's peak temperature compared to Propane.

Refillable Propane Cylinders - M14 x 1,5 valve. This cylinder contains pure Propane and operates at a higher pressure meaning it's suitable for demanding applications like brazing. Propane allows the torch to be used upside down with no flare-ups in case you are in tight spaces and can't use the torch in it's upright position and has a lower ignition point so it can be used during colder weather. This cylinder can be refilled. Consult with your local regulations about refilling.

For all weather conditions in combination with torch systems:

Refillable Propane Cylinders - M14 x 1,5 valve. Larger refillable cylinders ranging from 350 - 2000 grams that are suitable for torch systems. Contains Propane and mostly used by professional users in their daily applications such as soldering, brazing, sheet metal brazing. These cylinders can be refilled. Consult with your local regulations about refilling.

Yes, LPG can be harmful to your health if not handled properly:

  • Inhalation of high concentrations can cause dizziness, headaches, or even suffocation (it displaces oxygen).
  • Leaks in enclosed spaces can lead to fire or explosion risks.
  • Prolonged skin contact with liquid LPG can cause cold burns (frostbite).

Used safely and with good ventilation, LPG is safe. Always follow safety guidelines.

If you are selling LPG and need storage, we recommend you to check with your local municipal since you might need a permission to store and sell LPG. This varies from countries and also regions, therefore please consult with your local municipal.

If you are a user that uses LPG with a torch system or handle, make sure to read the Safety Data Sheet and safety instruction on the cartridge / cylinder.

Some general rules are:

1. Store and transport the cartridge / cylinder in a upright position. During storage, make sure it's well ventilated.

2. When you are done working, always make sure to shut off the valve of your torch and disconnect it from your gas cartridge / cylinder for maximum safety.

3. If you are operating a business (for example a workshop) and have many cartridges / cylinders, follow your local regulations regarding signage of dangerous goods. This is important in case of a fire / accident, the fire services will be able to identify which type of gas is stored and will proceed accordingly.

The theoretical temperature of a flame is approx. 1 925º Celsius (3 497º Fahrenheit). In practice, this temperature is not reached when heating an object. The flame temperature depends on the size of the object, the type of flame, the size of the burner and how long the object in question is heated. Depending on your applications and the object you are trying to heat, it's important to adapt accordingly and consult with the supplier of the material.

Gas Expansion & Pressure Drop

Inside the cartridge or cylinder, LPG is stored as a liquid under pressure. When you open the valve, the pressure drops, and liquid LPG rapidly evaporates into gas. This phase change absorbs heat from the surroundings, including the metal container.

Heat Absorption from the Cylinder Walls

As the gas evaporates, it draws heat away from the metal walls of the cartridge or cylinder, making them feel cold to the touch. In extreme cases (high flow rate or continuous use), frost can form on the outside because moisture in the air condenses and freezes on the cold surface.

The transportation of LPG is regulated by ADR which handles the transportation, packaging and labeling of dangerous goods.

If you sell LPG, it's important that you are in line with ADR regulations. Click here to read more.

If you are a professional user of LPG, read the Safety Data Sheet that contains information for transport and storage.

We recommend that you contact a professional gas filling supplier. They also do a safety check on your cylinder when refilling.

Disposable Cartridges / Cylinders do not have an expiration date.

Refillable Cylinders usually undergo a regular safety inspection when you refill at your gas filling supplier.

LPG is considered a relatively clean-burning fuel compared to other fossil fuels.

It produces fewer carbon dioxide (CO₂) emissions than coal, gasoline, or diesel when burned. It emits less particulate matter (PM), nitrogen oxides (NOₓ), and sulfur oxides (SOₓ), reducing smog and air pollution. It burns efficiently with minimal residue, reducing waste and pollution.

It’s a byproduct of crude oil / natural gas processing and therefore does not have an incremental impact on greenhouse gas emissions.

However, it’s still a fossil fuel and does contribute to carbon emissions. We therefore always recommend shutting off the torch when not in use to reduce carbon emissions.

Yes. Our gas cartridges / cylinders are manufactured according to certain regulations.

Gas Cartridges: EN 417
Gas Cylinders: ISO 11118

A Safety Data Sheet (SDS) is a document that provides detailed information about the properties, hazards, handling, and safe use of a chemical product. It is essential for workplace safety and regulatory compliance, especially for hazardous substances like fuels, adhesives, and industrial chemicals. 

Key Sections of an SDS: 

  1. Identification – Product name, manufacturer details, and recommended uses. 

  2. Hazard Identification – Potential risks, such as flammability, toxicity, or environmental hazards. 

  3. Composition/Ingredients – Chemical components and concentrations. 

  4. First-Aid Measures – Steps to take in case of exposure through inhalation, skin contact, or ingestion. 

  5. Fire-Fighting Measures – Suitable extinguishing methods and precautions for fires involving the substance. 

  6. Accidental Release Measures – Procedures for containment and cleanup of spills or leaks. 

  7. Handling and Storage – Safe handling practices and storage conditions. 

  8. Exposure Controls & Personal Protection – Recommended protective gear (e.g., gloves, goggles, respirators). 

  9. Physical and Chemical Properties – Information such as boiling point, flashpoint, and appearance. 

  10. Stability and Reactivity – Potential reactions, incompatibilities, and decomposition risks. 

  11. Toxicological Information – Health effects and exposure risks. 

  12. Ecological Information – Environmental impact and biodegradability. 

  13. Disposal Considerations – Proper disposal methods and regulations. 

  14. Transport Information – Shipping classifications and safety precautions. 

  15. Regulatory Information – Compliance with national and international safety laws. 

  16. Other Information – Additional safety details or revisions. 

SDS are a requirement globally when selling / distributing hazardous substances. 

A UFI code (Unique Formula Identifier) is a 16-character alphanumeric code used in the European Union to uniquely identify hazardous chemical mixtures. It is part of the EU’s CLP Regulation (Classification, Labeling, and Packaging) and is required for products classified as hazardous under Annex VIII of the CLP Regulation.

Our SDS are based on the regulation 1907/2006 annex II and 1272/2008 where EU 2020/878 is included.

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