Spotting a huge spider or a menacing-looking rat is scary, but so too is a sudden blackout or a light fitting crashing to the floor in the dead of night. But do you know what’s even scarier when you’re at home? The whiff of gas.
A gas leak is one of those situations where knowing exactly what to do could genuinely save your life. With approximately 5 million Australian households using natural gas and over 11 million gas appliances in homes across the country, understanding gas safety isn’t just helpful, it’s essential.
This guide explains how to spot the warning signs of a gas leak, the immediate steps to take to keep everyone safe, who to call, and also covers the causes, health risks, prevention tips, costs, and legal responsibilities every Australian household should know.
What Causes a Gas Leak?
A gas leak occurs when gas unintentionally escapes from pipes, appliances, or cylinders due to damage, corrosion, poor installation, or external factors.
Common causes include:
- Old, rusted or damaged pipes
- Gas appliances with worn seals, loose fittings or faults
- Poor or unlicensed installation work
- Underground movement from roots, soil shifting or construction
- Extreme weather events causing pipe cracks
- Accidental damage during excavation or renovation work
Before any excavation work, always contact Before You Dig Australia to prevent damaging underground gas lines and ensure safety compliance.
A potential gas leak should always be taken seriously and investigated immediately. Even small leaks are extremely dangerous, which is why prevention and fast action matter.
How to Spot a Gas Leak
To detect a gas leak, always be alert for the strong, distinctive odour added to natural gas and LPG, which is designed to help you quickly identify a potential leak and prevent accidents.
Do you smell rotten eggs? That could be the additive called mercaptan which is deliberately added to LPG and natural gas to alert you. Natural gas is actually odourless on its own, so this added smell is your first and most important warning system. If you smell gas inside your home, treat it as a serious safety concern and take immediate action.
Do you hear hissing or whistling, or see hazy air? Those are signs of gas escaping from an appliance, pipe or connection. A persistent hissing sound near gas lines often indicates high-pressure gas escaping, and these sounds may be especially noticeable during quiet moments.
Has part of your garden suddenly died off? That could be an underground gas line leak causing dead patches in your lawn and plants. One Sydney homeowner noticed their plants dying in a line across the front yard, which turned out to be a leaking underground pipe.
Do you feel unwell? A slow gas leak can be invisible but still dangerous. Common symptoms include headaches, dizziness, nausea, difficulty breathing or worse. The tricky part is that these symptoms can seem like a common cold or flu. The key difference? Gas leak symptoms often improve when you leave the house and worsen when you return.
Is your gas bill unusually high? A sudden spike in your gas bill without a change in usage may indicate a leak or inefficiency in your gas system that’s worth investigating.
What colour is your flame? A healthy gas appliance should have a blue flame. A yellow or red flame may signal incomplete combustion or a possible gas leak, and you should have the appliance serviced promptly.
Natural Gas vs LPG: Key Differences at a Glance
Understanding the type of gas in your home can help you respond appropriately during a leak and communicate clearly with emergency services.
| Feature | Natural Gas | LPG (Liquefied Petroleum Gas) |
|---|---|---|
| Weight | Lighter than air – rises and disperses | Heavier than air – sinks and pools |
| Where it collects | Ceilings, roof spaces, upper floors | Basements, cupboards, low-lying areas |
| Supply method | Mains pipeline connection | Cylinders or bottles |
| Shut-off location | Gas meter (usually front of property) | Cylinder valve |
| Ventilation priority | Open high windows and doors | Ventilate low areas first, then upper |
| Common uses | Cooktops, heating, hot water systems | BBQs, portable heaters, rural properties |
| Identification | Check your gas bill or meter | Look for gas bottles on property |
Both gas types use the same mercaptan odorant (that rotten egg smell), so detection methods remain similar. The key difference lies in how you ventilate your home during an emergency.
Natural gas is lighter than air, so it rises and disperses outdoors but can still trap and explode in enclosed ceiling spaces. In emergencies such as bushfires or gas leaks, turning off your natural gas supply can help prevent leaks and explosions.
LPG is heavier than air, collecting in basements, cupboards, garages, and low-lying areas, making it particularly dangerous indoors. Since it sinks, it can pool in dangerous concentrations under floorboards and in laundries, areas that natural gas would typically escape from.
Knowing which type you use (you’ll see it on your bill or cylinder) will help you report and describe issues clearly to emergency services, and know how to turn off your gas supply in an emergency.
Health Risks of a Gas Leak
Leaking gas doesn’t just smell bad, it’s bad for your health. Common short-term symptoms include:
- Headaches, nausea, dizziness
- Fatigue and confusion
- Irritated eyes, throat or chest
- Difficulty breathing
Prolonged exposure can lead to carbon monoxide poisoning, which is odourless, dangerous and even fatal. Carbon monoxide is produced when gas appliances don’t burn fuel completely, often due to poor installation or lack of maintenance.
If you ever feel ill indoors but better outside, that’s a major warning sign. The elderly, children, unborn babies, and people with heart disease and anaemia can be particularly susceptible to carbon monoxide poisoning.
Symptoms of Carbon Monoxide Poisoning
Carbon monoxide deserves special attention because it’s the silent killer. This colourless, odourless gas comes from faulty gas appliances and can be deadly. Watch for:
- Persistent headaches
- Drowsiness and fatigue
- Nausea and vomiting
- Shortness of breath
- Confusion or difficulty concentrating
- In extreme cases: loss of consciousness
To help with a diagnosis, let your medical professional know if you feel better when in the fresh air or if other members of the house, including pets, have similar symptoms.
Can Pets Detect a Gas Leak?
Your pets may actually notice a gas leak before you do. Animals have heightened senses and can react to environmental changes that humans might miss.
Signs your pet may be detecting a gas leak:
- Unusual restlessness, pacing, or agitation
- Reluctance to enter certain rooms they normally frequent
- Excessive sniffing around gas appliances or specific areas
- Whining, barking, or vocalising without apparent cause
- Lethargy, confusion, or appearing “off” (especially in smaller pets)
- Nausea or vomiting
Smaller animals like birds, cats, and small dogs are particularly vulnerable to gas exposure because of their faster respiratory rates and smaller body mass. Historically, canaries were used in coal mines precisely because they would show symptoms of gas exposure before humans, serving as an early warning system.
If your pet is behaving strangely and you notice any other potential signs of a gas leak, take their behaviour seriously. Evacuate with your pets immediately and have the situation assessed by professionals.
Outdoor Signs of a Gas Leak
Gas leaks aren’t confined to your kitchen or living room. If you’re concerned about handling gas leaks outside your home, watch for these warning signs outdoors:
- Dead or discoloured grass over buried pipelines
- Bubbling puddles or damp areas
- Gas smells around your meter
- Hissing or whistling from external pipes, cylinders or fittings
- Dust blowing from a hole in the ground
- White mist or fog in unexpected areas
Check your meter box for the main gas shut-off valve, which is usually located inside or near the meter box. Never ignore outdoor signs. Buried leaks are just as hazardous as indoor ones, and if you notice any of these signs outside your home, contact your gas distributor immediately.
Gas Leak in House: What To Do (10 Steps)
If you even suspect a leak, don’t panic, but act quickly and decisively. Here’s your step-by-step emergency response:
1. Act quickly and calmly – Stay level-headed and move with purpose. Panic can lead to mistakes.
2. Evacuate – Get all people and pets out immediately. Open windows and doors if time allows, but don’t delay your exit.
3. No flames or sparks – Don’t switch anything on or off. No stoves, no lights, no phones indoors. Even a small spark could ignite accumulated gas. If a gas fire is already present, do not attempt to extinguish it yourself. Move to safety immediately and let emergency services handle it.
4. Turn off the gas supply – If safe to do so, locate your gas meter (usually in a metal box at the front of your property) and rotate the valve 90 degrees to the horizontal “off” position. For LPG, close the cylinder valve. If you’re unsure or it feels unsafe, skip this step and evacuate.
5. Call emergency services – If you need police, fire or medical assistance right now, there’s no number to call except 000.
6. Non-emergency assistance – If you still think the police need to know about your situation but no one’s life is in immediate peril, the number to call is 131 444.
7. Call 1800 GAS LEAK – Report a gas leak, especially if you can still smell it in the street or beyond your own home, by calling 1800 GAS LEAK (1800 427 532). Don’t worry, you can call 24 hours a day, 365 days a year.
8. Call your gas provider – There are multiple gas providers in and around Sydney, so check a recent gas bill and call the one relevant to your property. If they have a customer service or emergency contact number, that’s the one to call.
9. Call local authorities – If you’re at a loss or need help from your local authorities or government agencies to report a gas problem, try the New South Wales Department of Planning, Industry, and Environment, or the Energy and Water Ombudsman NSW.
10. Call your neighbours – Warn those nearby in case they are also at risk, especially if you can smell gas in the street.
Important: Do not attempt to relight a pilot light or operate any gas appliance until the area has been declared safe by emergency services or a licensed gas fitter from your Australian gas provider.
Gas Leak Emergency Contacts by State
Having the right numbers saved in your phone before an emergency occurs can make all the difference. Here’s a quick reference for Australian gas emergency contacts:
| State/Territory | Gas Distributor Emergency Line | Network |
|---|---|---|
| NSW | 1800 GAS LEAK (1800 427 532) | Jemena, Australian Gas Networks |
| VIC | 132 771 (AusNet) / 132 691 (Multinet) / 1800 GAS LEAK (AGN areas) | Multiple distributors |
| QLD | 1800 GAS LEAK (1800 427 532) | Australian Gas Networks |
| SA | 1800 GAS LEAK (1800 427 532) | Australian Gas Networks |
| WA | 13 13 52 | ATCO Gas |
| ACT | 132 771 | Evoenergy |
| TAS | 1800 438 234 | Tas Gas Networks |
For all states, life-threatening emergencies: Call 000 immediately.
Non-emergency police assistance: Call 131 444.
Your gas distributor’s specific number should also appear on your gas bill. It’s worth saving this number in your phone contacts now, while you’re thinking about it. During an actual emergency, you won’t want to be searching through paperwork.
What Happens When a Gas Fitter Arrives?
Once you’ve reported a gas leak and a licensed professional arrives, here’s what you can expect during the inspection and repair process.
Step 1: Initial Safety Assessment The gas fitter will first confirm the area is safe to enter. They’ll use portable gas detection equipment to measure gas concentrations in the air and identify whether levels are within safe working limits.
Step 2: Source Identification Using specialised electronic detectors, the fitter will systematically check your gas meter, pipework, connections, and appliances to pinpoint exactly where the gas is escaping. This process may involve visual inspection, electronic gas “sniffing” along pipe runs, pressure testing of your gas system, and checking appliance connections and seals.
Step 3: Isolation and Repair Once located, the fitter will isolate the leak and carry out necessary repairs. This might involve replacing worn seals or washers, tightening loose connections, repairing or replacing damaged pipe sections, or servicing faulty appliances.
Step 4: System Testing After repairs, the entire system undergoes pressure testing to confirm no other leaks exist. The fitter will also check that all appliances are operating correctly, with proper flame colour (blue, not yellow) and adequate ventilation.
Step 5: Compliance Certificate For any significant gas work, your fitter will issue a gas compliance certificate. This document confirms the work meets Australian standards and is required for insurance purposes and future property sales.
Step 6: Safety Clearance Finally, the fitter will confirm when it’s safe to re-enter your home, provide ventilation recommendations, and answer any questions about ongoing maintenance or safety precautions.
How Long Should You Air Out Your Home After a Gas Leak?
Once a licensed gas fitter has repaired the leak and declared your home safe, you’ll still need to ventilate thoroughly before settling back in.
The timeframe depends on several factors:
For minor leaks (small connection issue, caught quickly): 15 to 30 minutes of cross-ventilation with all windows and doors open is typically sufficient.
For moderate leaks (noticeable smell throughout one room): Allow 1 to 2 hours of ventilation. Use fans to assist airflow if the area has been cleared by professionals.
For significant leaks (strong smell, multiple rooms affected, or leak went undetected for some time): Your gas fitter or emergency services may recommend 2 to 4 hours or longer. In some cases, they’ll use detection equipment to confirm gas levels have returned to safe concentrations before clearing re-entry.
Practical tips for airing out your home:
- Create cross-ventilation by opening windows on opposite sides of each room
- If you have ceiling fans, turn them on once the area has been cleared (not before)
- Pay extra attention to enclosed spaces like cupboards, laundries, and under-stair areas
- For LPG leaks, focus on ventilating low-lying areas where the heavier gas may have pooled
- Don’t rely on smell alone, as gas odour can linger even after concentrations drop to safe levels
When in doubt, ask your gas fitter for specific guidance. They can test the air quality and confirm when it’s genuinely safe to return.
Gas Appliances and Maintenance: Keeping Your Home Safe
Keeping your home safe starts with looking after your gas appliances. Schedule a licensed gas fitter to service your gas heater and other gas appliances every two years, following the manufacturer’s recommendations.
Clean your gas cooktops and ovens regularly to prevent the buildup of fat and burnt food, which can increase the risk of gas fires and leaks. Always check your gas meter and the area around it for any unusual smells.
If you notice the smell of rotten eggs or hear a hissing sound, you could have a gas leak. In these situations, never operate electrical equipment close to the suspected leak, as even a small spark can ignite the gas. If you suspect a problem, don’t try to fix it yourself. Call a licensed gas fitter immediately to ensure your gas safety and protect your home from potential leaks.
Your hot water system is another common source of gas issues, particularly if it hasn’t been serviced regularly. Gas hot water units should be inspected alongside your other gas appliances.
Preventing Gas Fires in Your Home
Gas fires can start quickly if you’re not careful with ignition sources like lighters, matches, or electrical appliances. Prevention is always better than dealing with an emergency.
Never leave cooking oil or fat unattended on the stove, as it can catch fire and turn a small fire into a major emergency. Keep a small fire extinguisher and a fire blanket in your kitchen, and make sure everyone in your household knows how to use them.
Always use your gas appliances for their intended purpose. Don’t use a gas oven or cooker to heat your home, for example, as this creates carbon monoxide risks and fire hazards.
If you suspect a gas leak, open doors and windows to ventilate the area, and avoid using electrical switches or naked flames. Never attempt to repair a gas leak yourself. Instead, call a licensed gas fitter to handle the situation safely.
Protecting Underground Gas Lines: Before You Dig Australia
Many gas leaks in Australia result from accidental damage during excavation work, whether it’s a major construction project or simply planting a new tree in your backyard.
Before any digging on your property, you’re legally required to check for underground services. This is where Before You Dig Australia (BYDA) comes in. It’s a free national service that provides information about underground utility locations, including gas lines, water pipes, and electrical cables.
When to use Before You Dig:
- Installing a new fence, deck, or pergola
- Planting trees or large shrubs
- Building a garden bed with deep excavation
- Pool or spa installation
- Any construction or renovation work involving ground disturbance
How it works:
- Visit byda.com.au or call 1100
- Submit an enquiry at least two business days before you plan to dig
- Receive plans showing approximate locations of underground services
- Take appropriate precautions when working near marked lines
Hitting a gas line can cause immediate leaks, property damage, service disruptions to your neighbours, and serious injury. It can also result in significant repair costs and potential legal liability. The few minutes it takes to lodge a BYDA enquiry is well worth the peace of mind.
How to Prevent Gas Leaks
Some simple maintenance now can prevent emergencies later:
- Service all gas appliances every two years by a licensed fitter
- Install gas detectors or carbon monoxide alarms in appropriate locations
- Keep ventilation areas around stoves, heaters and hot water systems clear
- Never do it yourself, as all gas work must be performed by a licensed professional
- Never use gas appliances in a confined space, as gas accumulation can lead to hazardous conditions
- Check gas connections on appliances like dryers and BBQs periodically
- Replace old or corroded gas hoses before they fail
Choosing the Right Gas Detector for Your Home
While your nose remains your first line of defence, a quality gas detector provides an extra layer of protection, especially for slow leaks that may not produce an immediately noticeable smell.
Types of gas detectors:
| Detector Type | What It Detects | Best For |
|---|---|---|
| Natural gas detector | Methane (natural gas) | Homes connected to mains gas |
| LPG detector | Propane/butane | Properties using bottled gas |
| Combination detector | Both natural gas and LPG | Homes with multiple gas sources |
| Carbon monoxide alarm | CO from incomplete combustion | All homes with gas appliances |
Placement recommendations:
- Natural gas detectors: Install high on walls or ceilings (gas rises)
- LPG detectors: Install low, around 30cm from the floor (gas sinks)
- Carbon monoxide alarms: Install at breathing height in bedrooms and living areas
- Place detectors near (but not directly on) gas appliances
- Avoid placement near windows, doors, or fans where airflow may affect readings
What to look for when buying:
- Australian certification (look for compliance markings)
- Battery backup in case of power outages
- Test button for regular functionality checks
- Clear, loud alarm that can wake sleeping occupants
- Digital display showing gas concentration levels (optional but helpful)
Budget models start around $30-50, while more advanced units with smart home connectivity can cost $100-200. Given that a detector could save lives and property, it’s a relatively modest investment for significant peace of mind.
Replace batteries annually (or as recommended) and test your detectors monthly. Most units have a lifespan of 5-7 years before they need replacing entirely.
Who Is Responsible for Gas Leak Repairs?
Gas leak responsibilities in Australia are clearly defined, and knowing who handles what can save confusion during an emergency.
| Party | Responsibility | What This Covers |
|---|---|---|
| Gas Distributor | Gas meter and distribution network | Street mains, pipework to your meter, meter repairs |
| Homeowner | All gas infrastructure from meter onwards | Internal pipes, appliances, connections, flues, servicing |
| Tenant | Reporting and safe evacuation | Notifying landlord/property manager, not touching appliances |
| Landlord | Providing safe, compliant gas systems | Installation, maintenance, servicing, repairs, compliance certificates |
If a leak occurs at your meter or in the street, your gas distributor handles repairs at no cost to you. However, if the leak is between your meter and your appliances (or from an appliance itself), you’ll need a licensed gas fitter, and the cost falls to the property owner.
For renters, your job is straightforward: report the issue to your landlord or property manager immediately, evacuate safely, and avoid attempting any repairs yourself. Under Australian tenancy laws, landlords must ensure all gas appliances and fittings are safe and properly maintained.
Not meeting these obligations can result in fines, insurance issues or tenancy breaches.
Gas Leak Costs in Australia
Not all leaks come with a big bill, but it’s good to know what to expect:
| Service | Typical Cost |
|---|---|
| Emergency plumber/gas fitter call-out | $150-$250 after hours |
| Minor repairs (valve, seal, connector) | $150-$300 |
| Major jobs (pipe replacement, appliance repairs) | $500+ |
| Gas detector installation | $30-$200 per unit |
| Annual gas appliance service | $100-$180 |
Your insurance may cover sudden leaks or damage but won’t cover long-term neglect or DIY mistakes. Keeping records of regular servicing can support any insurance claims you need to make.
Why You Need a Licensed Gas Fitter
Licensed gas fitters are the only people who can legally:
- Install or service gas systems
- Test, repair and sign off appliances
- Provide compliance certificates for insurers
Using anyone else is illegal and dangerous. Licensed gas professionals carry an identity card with a photograph, stating what work they are qualified to perform. Your state’s regulator can help you find a licensed gas professional if you’re unsure.
When searching for a gas fitter, check that they are licensed and experienced. You can verify their credentials through relevant state or territory licensing bodies. For gas fitting services in Sydney, always confirm licensing before any work begins.
Frequently Asked Questions About Gas Leaks
Will a small gas leak fix itself?
No. Gas leaks get worse over time, not better. Even a minor leak can develop into a serious hazard, and the gas will continue escaping until the source is properly repaired by a licensed professional.
How long before a gas leak explodes?
It depends on gas concentration, ventilation, and the presence of an ignition source. There’s no safe window. Even a small spark can ignite accumulated gas at any time, which is why immediate evacuation and avoiding electrical switches is so critical.
Who pays for gas leak repairs if I rent?
Usually the landlord, unless the tenant caused the leak through misuse or negligence. Tenants should report suspected leaks immediately and avoid attempting any repairs themselves.
Can I check for gas leaks myself?
You can do a basic check safely using soapy water on connections. If bubbles form, there’s a leak. Never use a flame to check for leaks. If you suspect a leak, do not attempt to operate any gas appliance or relight pilot lights. Always follow safety guidelines and contact a qualified professional for proper inspection.
How often should gas appliances be serviced?
Every two years is the standard recommendation for most gas appliances, including heaters, cooktops, and hot water systems. Regular servicing helps identify potential issues before they become dangerous leaks.
Is the gas smell always noticeable during a leak?
Not always. Very slow leaks may not produce a strong odour, and some people have a reduced sense of smell. This is why gas detectors and carbon monoxide alarms provide valuable backup protection.
Gas Leak What To Do: Call Rapid Service Plumbing
Gas emergency all sorted? Remember, Rapid Service Plumbing also offer 24-hour Sydney emergency plumbers and gas fitting services. If you detect that familiar and foul whiff of gas, give our friendly, licensed and attentive team a call and we’ll know exactly what to do instantly.
Once any emergency is sorted, we’ll professionally inspect your entire gas system and all appliances to get to the bottom of what’s wrong and put it right or replace it.
Need a Sydney gas fitter? For 24/7 services, advice, obligation-free quotes and fully-guaranteed workmanship for life, Rapid Service Plumbing will know what to do if you have a gas leak. Never hesitate to give us a shout.
Key Takeaways
- If you smell gas, evacuate immediately and call 000 for emergencies or 1800 GAS LEAK to report
- Never use electrical switches, phones, or create sparks near a suspected gas leak
- Know your gas type (natural gas vs LPG) as they behave differently and require different ventilation approaches
- Service all gas appliances every two years with a licensed gas fitter
- Install gas detectors and carbon monoxide alarms for early warning protection
- Always use Before You Dig Australia before any excavation work on your property
- Only licensed gas fitters can legally perform gas work in Australia
- Keep emergency contact numbers saved in your phone before you need them
