Compressed gases are used in workplaces everywhere, and in Australia they are classified as Dangerous Goods. Extreme care must be taken when storing and handling gas cylinders, and it is important to know the different cylinder types and the unique risks they present.
This blog is the first in a series of blogs that outline the safe storage and handling of gas cylinders. This blogs will introduce you to three types of cylinders common to workplaces across Australia and the different risks they present. These include:
- High Pressure Industrial Gas Cylinders
- Acetylene Cylinders
- LPG Cylinders
Because it’s an introduction only, we strongly encourage you to keep reading through our full blog series on gas cylinders; it’s an excellent way to gain a greater understanding of your legal obligations without having to interpret long, detailed legislation or complex Australian Standards.
TIP: if you need to know how to manage the risks relating to storing the different types of gas cylinders at your workplace, download our free eBook Gas Cylinder Storage: Compliance and Safety Requirements today.
1. High Pressure Industrial Gas Cylinders
High pressure industrial gas cylinders are made from both aluminium or steel, and enable compressed gases to be safely used and transported. Common industrial gases like Nitrogen, Helium, Hydrogen, Oxygen and Carbon Dioxide are all stored inside these cylinder types.
Gases under high pressure can present serious health and safety hazards when not stored and handled correctly. So it’s essential to understand both the health hazards (toxic gases, corrosive gases, asphyxiants) of the gases you use, as well as the physiochemical hazards of the cylinders themselves.
While many compressed gases are flammable, corrosive and self-reactive, even non-flammable and non-toxic gases can become dangerous when cylinders become loose, heated or start to disperse gas in an uncontrolled manner. Many workplace accidents and fatalities have resulted from unsecured cylinders releasing gas in an uncontrolled manner. This can turn the gas cylinder into a torpedo-like projectile.
Risks associated with high pressure industrial gas cylinders
- Oxidizing gases can cause combustible substances to spontaneously ignite, they need to be separated from flammables, heat and ignition sources.
- Fires and explosions associated with flammable gases, they must be stored correctly away from heat, oxidisers and ignition sources.
- Gas leaks from damaged or faulty cylinders, valves and connections can create unsafe exposure levels to toxic, corrosive and flammable gases. Cylinders and manifolds should be inspected, maintained and serviced regularly by qualified technicians.
- High pressure industrial gas cylinders are heavy and very awkward to manoeuvre. Apart from manual handling injuries, dropping or causing cylinders to strike each other can damage valves and cause gases to rapidly disperse. Staff need to be well trained in manual handling techniques and in many instances, you’ll need to purchase industrial lifting and carrying devices.
- Gas cylinders can easily fall or be knocked over causing air contamination and dangerous free flow. Cylinders should be secured on trolleys or stored in gas bottle cages.
2. Acetylene Cylinders
Acetylene is an excellent fuel for heating because it is very efficient and it burns extremely hot. Used for industrial welding and cutting, acetylene mixed with oxygen is the only flammable gas capable of welding steel.
But acetylene is a very unstable gas, and capable of undergoing a dangerous chemical reaction known as decomposition. Decomposition generates a lot of heat, which can cause acetylene to ignite spontaneously. If pure acetylene is dispensed into the atmosphere at a pressure greater than15psi, it can violently decompose and explode by itself without a spark or flame.
Because of the high risk of decomposition, acetylene cannot be stored in the same way as other gases. Instead, this gas must be dissolved in a solvent (usually acetone) and supplied in special cylinders containing a porous filler material called a monolithic porous mass.
Risks associated with Acetylene cylinders
As you might expect, acetylene cylinders require additional precautions and care.
- Decomposition can be triggered by a flash-back from welding and cutting equipment. Employees should be properly trained in safe welding and cutting techniques.
- Acetylene can decompose when exposed to intense heat, cylinders should be stored in a fireproof area away from heat sources.
- To prevent the acetone and acetylene from separating, acetylene cylinders must be kept upright at all times.
- Acetylene reacts explosively with pure copper, brass, silver and mercury, so alloy valves and reticulation systems must only contain small percentages of these metals.
- Employees must use extreme care when handling these cylinders as rough handling or heating due to shock may result in a delayed explosion. Make sure they are not dropped or even allowed to strike one another.
- Valves must be opened slowly to prevent rapid dispensing of the gas. If acetylene flows too quickly it can create static electricity sparks or solvent loss. Either event will result in decomposition and an explosion.
3. Liquified Petroleum Gas (LPG) Cylinders
LPG is used in many workplaces for cooking, heating, cutting and fuelling vehicles like forklifts. But LPG is highly flammable as well as being an asphyxiant, so extreme care must be taken when handling and storing the gas cylinders. Because LPG is so common — we are so used to taking those cylinders camping or attaching them to our outdoor BBQ’s at home — sometimes we don’t give this Dangerous Good the respect is deserves.
Risks associated with LPG Cylinders
In addition to the risks associated with high pressure industrial gases, LPG also has the following risks and hazards.
- LPG is extremely flammable and cylinders can explode if involved in a fire. Use and store LPG cylinders away from heat, oxidisers and ignition sources. LPG can ignite from burning cigarettes, open flames, spark producing switches/tools, heaters, naked lights, pilot lights, mobile phones etc, even the remote control from your car’s central locking system.
- LPG is denser than air, so it will collect in low lying areas like pits and basements presenting an asphyxiation, fire or explosion hazard. Keep cylinders, valves and regulators well maintained and regularly serviced to avoid leaks. Turn off valves when the cylinder is not being used and make sure that fittings like welding torches are removed when the cylinder is not being used or in storage.
- LPG is an asphyxiant so it must be used in well ventilated areas. Don’t use or store the gas in confined spaces, closed rooms or areas that are not ventilated.
Storing and handling gas cylinders must be carefully managed to meet the requirements of both the Australian Standard AS 4332—2004 The storage and handling of gases in cylinders as well as the National Code of Practice Storage and Handling of Workplace Dangerous Goods. If you need clear and actionable advice for managing the risks associated with storing gas cylinders why not download our free eBook Gas Cylinder Storage: Compliance and Safety Requirements.