Gas cylinder mounting and restraints

LP Gas cylinders are a common feature on Australian recreational vehicles, providing an efficient and practical energy source for cooking, heating, and refrigeration – especially in unpowered camping locations. However, they also pose significant risks if the gas system or its components malfunction.

Gas cylinders store gas in liquid form under high pressure. Any damage or breach to a cylinder or its immediate connections can lead to the uncontrolled release of gas and, in the presence of an ignition source, potential explosions. Gas installation standards have been developed to minimize and, where possible, eliminate these risks.

Rules and regulations

Recreational vehicle gas installations are required to comply with Australian Standard AS/NZS 5601.2:2020 Gas Installations, Part 2: LP Gas Installations in Caravans and Boats for Non-Propulsive Purposes. Section 3.2 of this standard sets out the installation requirements for gas cylinders mounted on a recreational vehicle.

Importantly, the gas cylinder mounting requirements of the standard apply to any gas cylinder mounted on a recreational vehicle. This includes, but is not limited to:

  • Cylinders mounted externally on the A-frame.
  • Cylinders mounted inside a gas compartment.
  • Cylinders connected to fixed piping.
  • Spare cylinders stowed or mounted for transport.

Secure mounting

Cylinders must be secured in place by attachments that withstand a load equal to four times the weight of the full cylinder and its fittings, in all directions. (Refer clause 3.2.1.)

Externally-mounted cylinder restraints must consist of metallic components. Restraints located completely within a cylinder compartment or locker may be constructed from other materials. However, these must still be able to withstand the required loads (as described above).

Some elements of a good restraint system:

  • Strong attachment to the vehicle structure – secure bolts, sufficient welding.
  • Ensure any plastic mounts are sturdy – no flex.
  • Secure grip around the cylinder – tight straps, sufficient strap width or multiple straps.
  • Restrain only one (1) cylinder in each retention strap.
  • Secure the base of the cylinder against movement – non-slip materials, recessed cavity, locating rings or fittings around the base.

Some things to avoid:

  • Self-drilling screws, tack welds.
  • Webbing straps encircling more than one cylinder.
  • Webbing straps that cannot be tightened around the cylinder body.
  • Flexible plastic mountings.
  • Metal-on-metal contact with the cylinder surface – mounting straps, webbing ratchet fittings.
  • Unsecured base of cylinder.

The cylinder mounting can be very simply tested by attempting to push or rock the gas cylinders by hand. A good restraint system should prevent movement of the cylinders, either horizontally along the base/floor, or in a tilting motion.

Protection of cylinder

Gas cylinder mountings, while ensuring sufficient strength, must not excessively load or damage the cylinder. This is especially important to consider in vehicle installations, where there is considerable vibration exposure due to road inputs through the vehicle.

When metallic components are used in the cylinder restraints, an insulating strip must be present between the surface of the cylinder and the restraints. For example, a rubber strip between a metallic clamping band and the cylinder.

The mounting system must also ensure there is no physical contact between adjacent cylinders.

Spare cylinders

Any cylinder that is stowed in or on a recreational vehicle is deemed to be installed for the purposes of compliance with the gas standard. Therefore, it must meet the same mounting requirements, even if the cylinder is not connected to appliances or piping when stowed. (Refer clause 3.1.10.)

Summary

Regardless of its location, any gas cylinder that is stowed or mounted on a recreational vehicle must be securely restrained against movement and protected from damage.

Further details can be found on the RV Gas Ready website.

This article was prepared by the RVMAP Compliance Team, which includes some of the most experienced, caravan-specific inspectors in the country. Any questions regarding this information can be emailed to [email protected].

Disclaimer: The information provided in this document is general and is provided in good faith. Readers must make their own investigations or seek specific advice on their particular individual circumstances. Caravan Industry Association of Australia Limited, its employees, contractors and agents are not liable in any way including, without limitation, for negligence, in connection with this document or for any errors in or omissions from this document, or any new understanding of the law whether arising from any legislative instruments or the decision of any court or tribunal, whether before or after this document was prepared, first published, distributed or used.