LPG Gas Bottle Clearance Distances: The Complete AS/NZS 5601.1 Guide for Gas Fitters

By Shelton Allenberg · QBCC Licensed Plumber & Gas Fitter (Lic. 15371578) · Gold Coast, QLD · Published 2026-07-27

Getting LPG cylinder clearances wrong is one of the most common non-compliances picked up during gas installation audits. The distances seem simple on paper, but on a real job site — with split systems, NBN boxes, pool pumps, and stormwater grates all competing for wall space — it gets complicated fast.

This guide covers every clearance distance required under AS/NZS 5601.1:2022 (Section 5.3) and AS/NZS 1596:2014 for residential LPG cylinder installations in Australia. We've included a compliance diagram you can reference on site.

LPG Cylinder Clearance Diagram

The diagram below shows all minimum clearance distances from the centre line of an LPG cylinder to surrounding hazards, openings, and ignition sources:

All horizontal measurements are taken from the centre line of the LPG cylinder. Diagram for reference only — always verify against the current edition of AS/NZS 5601.1.

Complete Clearance Distance Table

The following table summarises every minimum clearance distance for residential LPG cylinder installations under AS/NZS 5601.1:2022 and AS/NZS 1596:2014:

What Counts as an Ignition Source?

This is where most non-compliances occur. Gas fitters often think of ignition sources as open flames, but the definition under AS/NZS 1596:2014 is far broader. An ignition source is any device or equipment capable of producing a spark, arc, or surface temperature sufficient to ignite an LPG-air mixture.

The following are all classified as ignition sources and must maintain the 1.5m (exchange) or 3.5m (tanker fill) exclusion zone:

• Electrical switches and switchboards — including light switches on external walls
• Power points and GPOs — even if nothing is plugged in
• Air conditioning condensing units — the outdoor split system unit contains a compressor motor
• Heat pump hot water systems — the compressor unit is an ignition source
• Pool pumps and filtration equipment — electric motors produce sparks
• NBN connection boxes and Telstra NTDs — classified under AS 60079 as potential ignition sources
• Outdoor lighting — including sensor lights and decorative garden lighting
• Irrigation solenoids — the electromagnetic coil can produce a spark
• Bug zappers and insect lights — produce continuous arcing
• Gas appliances — hot water systems, BBQs, patio heaters, pool heaters
• Electric vehicle chargers — contactors and relays inside the unit
• Solar inverters — if mounted on an external wall within the zone

Why LPG Clearances from Drains Matter

LPG (propane/butane) is approximately 1.5 times heavier than air. In the event of a leak, the gas doesn't rise and dissipate — it sinks to ground level and flows into any below-ground depression. A stormwater grate, sewer inspection opening, or even a garden drainage channel can accumulate enough LPG to create an explosive atmosphere underground.

The 1.0m clearance to drains and pits is measured horizontally from the centre line of the cylinder to the nearest edge of the drain opening. This applies to:

• Stormwater grates and pits
• Sewer inspection openings (IOs)
• Garden drainage channels
• Basement window wells or light wells below ground level
• Any uncovered opening below the level of the cylinder relief valve

Exchange vs Tanker Fill: Why the Different Zones?

The 1.5m exclusion zone applies to standard exchange cylinder installations (where the gas supplier swaps empty 45kg bottles for full ones). The larger 3.5m zone applies to in-situ tanker fill installations where a bulk delivery tanker fills the cylinders on site.

The reason for the larger zone is simple: during tanker filling, there's a brief moment when the hose connection is made and broken where a small amount of LPG vapour is released. The 3.5m zone accounts for the potential vapour cloud during this operation.

If your customer wants automatic tanker delivery (which is more convenient and eliminates running out of gas), you need to plan the cylinder location with the larger 3.5m exclusion zone from the start. Retrofitting is often impossible once the house is built and electrical/HVAC equipment is installed.

Cylinder Placement Rules

Beyond clearance distances, AS/NZS 5601.1:2022 specifies several placement requirements:

• Upright and stable: Cylinders must stand vertically on a solid, level base (concrete slab or pavers). Never on grass, soil, or timber decking.
• Well ventilated: Cannot be in an alcove, enclosure, under a building, or under stairways. Natural ventilation must allow any leaked gas to dissipate freely.
• Not in traffic areas: Must be protected from vehicle impact if near driveways or parking areas.
• Relief valve unobstructed: The pressure relief valve at the top of the cylinder must have a clear discharge path — no walls, fences, or overhanging structures within the discharge zone.
• Line of sight for tanker: If tanker-filled, the driver must have clear line of sight from the delivery point to the cylinders while filling.

NBN Boxes: The Newest Compliance Headache

Since the NBN rollout, one of the most common compliance issues is the proximity of NBN connection boxes (or older Telstra NTDs) to gas cylinder installations. These boxes are classified as potential ignition sources under AS 60079 because they contain electronic components.

The WA Department of Mines, Industry Regulation and Safety issued a specific bulletin confirming that NBN and Telstra boxes must maintain the full 1.5m exclusion zone from gas cylinders. This applies regardless of whether the box is "low voltage" — the current standard prohibits installation inside the exclusion zone.

If you encounter an existing installation where the NBN box is within 1.5m of the gas bottles, the correct action is to notify the homeowner and recommend either relocating the gas bottles or having the NBN box relocated by a licensed cabler.

State-Specific Requirements

While AS/NZS 5601.1:2022 is the national standard, each state's technical regulator may impose additional requirements:

• Queensland (QBCC): Gas fitting work is Notifiable Work — lodge Form 4 with QBCC within 5 business days of completion. New gas installations require a compliance certificate.
• Victoria (ESV): Gas installations must be accepted by Energy Safe Victoria before commissioning. Compliance certificates required.
• South Australia (OTR): The Office of the Technical Regulator enforces the standard. Gas Bulletin #55 provides additional guidance on the 2022 changes.
• Western Australia (Building & Energy): Specific bulletins on ignition sources near LP gas cylinders. More prescriptive on NBN/Telstra clearances.
• New South Wales (Fair Trading): Gas work must be done by a licensed gasfitter. Compliance certificates lodged with Fair Trading.

Common Non-Compliances on Site

Based on audit data and field experience, these are the most frequent clearance violations gas fitters encounter:

1. Split system condenser within 1.5m — installed after the gas bottles, often by a different trade
2. NBN box within 1.5m — installed during the NBN rollout without checking gas clearances
3. Stormwater grate within 1.0m — common on narrow side passages where the house slab is close to the boundary
4. Sensor light above bottles — mounted on the same wall section as the cylinder bracket
5. Cylinders on grass or soil — no concrete pad, bottles sinking and tilting
6. Cylinders in an alcove — between a fence and wall with inadequate ventilation
7. Pool pump within 1.5m — common in rear yards where both the pump and bottles are on the same wall

What To Do When You Can't Achieve Clearances

On tight sites (townhouses, narrow lots, zero-lot-line builds), achieving all clearances simultaneously can be challenging. Here are your options:

• Relocate the cylinders: Move to a different wall or position that achieves all clearances.
• Fire-rated barrier: AS/NZS 1596:2014 allows a 2-hour fire-rated masonry wall between the cylinder and the hazard if the 1.5m distance cannot be achieved. The wall must extend at least 300mm above and to each side of the exclusion zone.
• Relocate the ignition source: If the gas bottles were there first, the other trade may need to move their equipment.
• Convert to exchange: If the site can't accommodate the 3.5m tanker fill zone, switching to exchange cylinders (1.5m zone) may solve the problem.
• Underground or remote tank: For new builds, an underground LPG tank or remote above-ground tank with piped supply may be the only compliant option.

Frequently Asked Questions

Can I install gas bottles under a carport or covered area?

Only if the area is open on at least two sides and provides adequate natural ventilation. A fully enclosed carport or garage is not permitted. The cylinder must also maintain all other clearances from ignition sources, openings, and drains within the covered area.

Does the 1.5m clearance apply to a switched-off powerpoint?

Yes. The clearance applies to the electrical fitting itself, regardless of whether it's switched on or off. A powerpoint contains internal contacts that can arc when a plug is inserted or removed.

What about a gas BBQ near the bottles?

A gas BBQ with a pilot light or piezo igniter is an ignition source. It must maintain the full 1.5m (exchange) or 3.5m (tanker fill) clearance from the LPG cylinder installation. This catches many homeowners who place their BBQ right next to the gas bottles for convenience.

Do these clearances apply to small 9kg camping bottles?

The clearances in AS/NZS 5601.1 apply to permanently installed LPG cylinder systems (typically twin 45kg). Portable cylinders connected to portable appliances (BBQs, camping stoves) are covered by the appliance manufacturer's instructions and general safety guidance, but the same principles of keeping away from ignition sources and drains apply.

Is a solar inverter an ignition source?

Yes. Solar inverters contain relays and contactors that can produce arcs during switching operations. If mounted on an external wall, they must maintain the 1.5m exclusion zone from LPG cylinders.

This article is general guidance only and does not constitute legal advice. Always verify compliance requirements with your state's technical regulator and the current edition of AS/NZS 5601.1 before commencing work. Information current as of July 2026.