A Marriage Where Sparks Never Fly
Brass + Cotton = LPG Safety
Have you ever wondered why almost all LPG valves and fittings are made from brass?
Safety is the reason but the “why” requires a bit of explanation...
What is Brass?
Brass is the broad term for a range of copper-zinc alloys.
Depending on the composition, the physical properties of the metal can vary.
This includes strength, machinability, ductility, wear-resistance, hardness, colour, anti-microbial, electrical conductivity, thermal conductivity and corrosion resistance.
Two qualities, the ability to form castings and great machinability, make brass the perfect choice for manufacturing precision valves and fittings.
Does Brass Spark?
Sparks generated by “friction” can commonly occur when other metals impact on each other or on other materials such as steel or concrete.
A mechanical or frictional spark is generated.
Unlike ferrous metals – metals containing Iron – which will generate sparks upon impact, brass does not spark on impact.
Brass is considered to be "non-sparking".
Brass also tolerates low temperatures.
This is important because LPG vapourisation can cause gas bottles and valves to become very cold.
Brass does not become brittle at low temperatures, unlike mild steel.
The need to avoid sparks in a flammable environment, such as around LPG gas vapour, is easy to understand.
The fact that brass does not spark makes it ideal for the coupling of LPG valves and hoses.
The perfect everyday examples are BBQ gas valves, regulators and autogas filling guns.
During the connection of these common LPG fittings, it is not at all unusual for the fittings to bang into each other.
Being made from brass means that these impacts do not generate any sparks, preventing possible ignition, if flammable gas vapour were to be present.
Anti-Static Cotton Clothing
In addition to using brass, LPG workers wear 100% cotton clothing to avoid generating static electricity.
Inasmuch as a single spark could cause ignition, if LPG vapour were present, the prevention of static electricity is a high priority.
A common complaint people have in the winter is that they get “zapped” when touching objects.
This is typically because they have dry skin and they are wearing polyester clothing.
The zap they feel is static electricity.
One of the best combinations for creating static electricity is dry human skin rubbing against polyester material.
Dry human skin has a great tendency to giving up electrons, becoming highly positive (+) in charge.
On the other hand, polyester is a material that attracts electrons when brought in contact with other materials.
It tends to gain a negative (−) electrical charge. The combination results in static electricity and sparks.
In addition, people working with LPG are always encouraged to touch a grounded surface before working on LPG connections.
This discharges any possible static electicity in a safe manner.
Here is a bit of brass related trivia…
Brass is Anti-Bacterial
Brass can help in the fight against hospital acquired infections, such as MRSA and other “Super Bugs”.
It has been shown that these pathogens, which can be spread by physical contact, will die in a few hours on brass and copper surfaces.
Stainless steel and plastics do not share this unique characteristic.
Brass is Recyclable
The recycling of brass is common around the world. Its high value provides great incentive to recycle.
Old gas valves and fittings are all recycled.
Making products from recycled brass is much more economical than using virgin brass.
Brass is a Bad Match for Acetylene
Talk about explosive marriages! Brass is not quite perfect.
Brass coming in direct contact with acetylene may form explosive acetylides.
Acetylene also forms explosive compounds with copper, copper salts, mercury/mercury salts, silver/silver salts and nitric acid.
Needless to say, the valves and fittings on acetylene cylinders are not made from brass.
The LPG industry is fine tuned for safety.
The use of brass fittings and cotton clothing are just two of the many safety precautions taken with LPG gas.
If it was possible for a company to be "Obsessive-Compulsive" about anything, it would be the Elgas concern for safety.
Nothing is more important than the safety of our customers, employees and the community.
Comments, questions or feedback?
The information in this article is derived from various sources and is believed to be correct at the time of publication. However, the information may not be error free & may not be applicable in all circumstances.