Gas Cylinder mounting and restraints
General Requirements
The requirements for correct installation of gas cylinders in a Recreational Vehicle installation are found in AS/NZS 5601.2:2020 Section 3.
Location
LP gas cylinders must be mounted:
- In a cylinder compartment or locker;
- On the drawbar or similar protected position on a caravan or camper trailer;
- Externally on the chassis of a caravan, under the skirt/bodywork.
The mounted location must be a well-ventilated area.
In general, gas cylinders must not be installed inside an RV living space. If this is unavoidable, additional storage requirements must be followed (refer clause 3.3.4.).
Restraints – Mountings
Gas cylinders must be mounted in attachments that can withstand a load equal to 4 times the weight of the full cylinder and fittings in all directions. The design, construction and fixing of the mounting system must demonstrate sufficient strength for this requirement and must not cause undue loading or damage to the cylinder.
- Ensure that any welded attachments and screw fixings are robust.
Note: Self-drilling Tec screws and tack welds are not recommended – they are unlikely to provide sufficient strength. - Ensure that any anchor straps hold the gas cylinder securely, preventing movement.
- Consider conducting load testing to verify the performance of your system.
All components of a cylinder mounting assembly are required to be metallic, except if the mounting system is entirely housed inside a gas compartment/locker.
To prevent corrosion of the gas cylinder materials, a rubber strip (or similar non-metallic protection) must be provided between the surface of the gas cylinder and the anchor straps.
A good example of a mounting system is shown in Figure 3.2.2 and includes the following:
- Metallic components
- Restraints that tighten firmly around the cylinder.
- Insulating strip between the cylinders and the restraints.
- At least 2 metallic supports connecting the cylinder restraints to a base plate or similar structure.
- Locating structure that prevents movement of the cylinder – eg locating rings in the base plate.
The requirements for securing gas cylinders against movement apply equally to gas cylinders located in a gas compartment/locker as to those mounted externally.
Clearances
Ignition sources must be kept clear of any gas cylinder, in line with the controlled area defined in Figure 3.1.8(A).
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Openings into the RV and air intakes to appliances must also be clear of any gas cylinder. This includes vents, openable windows, doors, unsealed compartments and any air intake of an appliance, regardless of fuel type.
The minimum clearances are defined in Figure 3.1.8(D). In summary, there must be at least 1000mm from the cylinder centreline to any opening, unless the opening is more than 150mm above the top of the cylinder valve.
Spare Cylinders
Any unconnected or spare gas cylinders must be stowed in the same way as for connected cylinders. This includes mounting methods, clearances and location requirements.
Orientation
A gas cylinder must be installed upright. This is important to ensure the correct function of the pressure release valve in case of excess pressure building up inside the cylinder. It also ensures that the vaporisation of the LP gas occurs efficiently to supply the installation and appliances.
Cylinders installed on a caravan drawbar should be orientated so that the relief valves discharge in a direction that is away from both the caravan and the towing vehicle.
Refer clause 3.1.4