What makes fuel-burning appliances the central hazard is the poisonous gas they can put out, a substance that eludes the senses; one cannot see, smell or taste it. That is the plain truth of the matter. In winter, with windows shut and perhaps an open-flued appliance or a make-shift form of indoor heating in use, carbon monoxide has a way of building up from a faulty gas heater before anyone is aware of the signs.
Prevention is the only sensible course of action. Have your gas appliances put through a professional service, follow established gas safety protocols and the instructions for every heater to the letter, put outdoor equipment where it belongs and fit a carbon monoxide alarm in the right place. As a writer and editor in Melbourne I have a practical rule: do not let the cold of a night persuade you to put combustion equipment to a use its maker did not design it for. I am Imogen Weatherby.
Why the risk is greater in winter
Australians will heat their homes differently when the weather turns and seal them up more tightly. It is a combination worth understanding so as to cut down on carbon monoxide exposure by the book rather than by guesswork or after symptoms present themselves.
CO, as it is usually called, is an invisible and odourless by-product of any carbon-based fuel that does not burn off completely, be it wood, charcoal, petrol, diesel or gas. The appellation “silent killer” is grim but for all that accurate since our human faculties are no match for detecting it.
Pollutants in a cold home
Doors and windows are closed to keep the warmth in, which means there is less fresh air coming in and a blocked flue or unsuitable appliance is all the more of a threat. One should be especially circumspect in a caravan, workshop, small flat or any enclosed outdoor area where contaminants can get concentrated in the limited air space.
You might think opening a window will fix a defective appliance, but it will not. There is too much at play in terms of room size, vent position and the wind. A window left ajar does not make it safe to run a patio heater, generator or barbecue inside.
Sources of CO
When household incidents occur it is down to poor ventilation or the fuel-burning equipment, or some of each. Being familiar with the usual suspects is the best way to manage gas safety over winter and head off an emergency.
You will not find carbon monoxide from an electric resistance heater, a heat pump or reverse-cycle air conditioner in the room because they do not burn fuel there. But give any appliance that does a closer look, even if it seems to be running fine.
Gas heaters and flues
If a gas heater is at fault, exhaust gases may find their way into the room or combustion is left incomplete. Open-flued types need the flue to expel what they produce and take their air from the room; the pressure in a well-sealed building or from an exhaust fan can upset this and a professional opinion is advisable.
An unflued gas heater puts its combustion products in the very space you occupy. If the unit is damaged or you are not abiding by local requirements and the instructions, there is an unflued gas heater danger. And never put a block in front of a permanent vent to stave off a draught, that gap is there for a reason.
Keep portable equipment outside
With a petrol or diesel engine you can have high levels of CO in short order, making the risk from a generator quite severe. They have no place indoors, far from any doors or vents. Do not assume a carport, verandah or garage is safe just because part of it is open.
The same goes for a barbecue. There is no point in taking a brazier, heat bead tray or camping stove in to cook or warm up. An outdoor heater indoors is not something you will find excused in the fine print; they are not made for an enclosed living room.
Some households are at higher risk
Anyone can be harmed by carbon monoxide, yet there are those who will be taken ill by an exposure sooner or have difficulty putting an end to it. Foreknowledge of a vulnerability is what allows a household to put in place the right alarms, heating and emergency provisions.
There are those who need special consideration: older adults, pregnant people, babies and children, as well as anyone with heart, lung or blood issues. And then there are sleeping members of the house, or persons under the influence of alcohol or sedatives, or with a mobility impairment; they might not be quick to respond to an alarm or even register the symptoms.
Situations That Catch People Out
A tenant will sometimes take for granted that a heater in situ has been serviced of late. One on holiday may put faith in a cabin or caravan heater one does not know. A family could put a portable appliance in the bedroom in the grip of a cold snap without seeing if it is allowed.
Then there is the notion that rural and remote places are of themselves well ventilated. Be it a generator by a caravan in the Pilbara, a camp stove in a tent off the Gibb River Road or a charcoal burner in a hut, the open bush outside is no safeguard. CO safety is a matter of the equipment, the enclosure and the airflow, not the postcode.
Recognise Symptoms Before Collapse
What presents itself can be like a case of flu, a migraine, food poisoning or your run of the mill winter bug. To see the pattern is to limit exposure and keep from having more than one person or pet in the building get steadily worse.
The usual signs of carbon monoxide poisoning are dizziness, headache, nausea and vomiting, weakness, shortness of breath, chest pain, tiredness and confusion. In a severe instance it can lead to collapse, seizures, loss of consciousness, injury to the brain or heart and death, not to mention poor coordination.
Watch The Place Pattern
If a number of occupants come down with the same thing, or a pet is unwell, or someone is better for being outdoors, look to the environment. Do not be fooled into thinking the property is safe for want of one classic symptom.
Nor can a blue gas flame or no soot be taken as proof of safety. Carbon monoxide is odourless; what you smell in supplied gas is an indicator of a leak, not a measure of CO. They are two different hazards and both warrant attention.
Read Current Australian Evidence Carefully
In 2026 the risks are still to be found in poor ventilation and appliances that have not been looked after. The source material does not offer a verified national total for 2026 incidents and to put forward an old figure as current would be disingenuous.
It is hard to make sense of Australia’s carbon monoxide poisoning numbers. Mild cases pass for something else and jurisdictions have their own way of reporting. What shows up in hospital admissions is only part of it. A council campaign or consumer survey is not a national prevalence rate until one has examined the methodology and the study population.
Separate Studies From Rules
Work done by UNSW Sydney and Nest has put household awareness of CO alarms in the spotlight in Australia but the survey does not set the country’s poisoning rate. Woollahra Council data may have its uses in the locality but is not indicative of every home here.
As for advice and the law, states and territories have their own way of doing things. The authorities be they NSW Health, Health Victoria, SA Health or the WA Government Energy Safety and Consumer Protection WA, but it is up to the resident to verify the rules for his tenancy and appliance. For sound guidance on symptoms and what to do in an emergency, there is the nationally oriented material from Healthdirect.
Prevent Exposure Before Heating
You will find it simpler to make a brief inspection ahead of the first cold weather than to contend with an alarm at 2 am. These protocols are about the essentials: proper maintenance and equipment, good ventilation and prompt action in an emergency.
Do not put it to one that an appliance is fine because it was last winter, nor attempt a repair on the spot; a heater will run and yet give off unsafe combustion products.
Safety Checklist
- Have a licensed gasfitter service as the manufacturer and state guidelines dictate.
- See to it flues, chimneys and wall vents are clear.
- Portable generators, barbecues, camping stoves and the like are not for indoor use.
- Do not heat a room with the gas oven or cooktop.
- Unflued heaters are subject to restrictions in small rooms such as a bathroom or bedroom.
- Make sure all in the house will know an alarm when they hear one and can get out of it.
- Any heater with soot, condensation or trouble with the pilot light should be put aside and damaged appliances replaced.
- Have a written CO safety checklist to hand with the details of your appliances and who to call in an emergency.
Alarms for the Australian Market
There is no better way to put an extra warning in place than with a carbon monoxide alarm, especially in rooms with fuel-burning appliances and around where one sleeps. While it is not a substitute for proper appliance use, ventilation or having things serviced, the alarm will put occupants on notice before they are aware of any symptoms.
When it comes to CO detector installation in Australia, be sure to pick an alarm made for this market. Have a look at the packaging and instructions for warranty, certification details and an expiry date. Do not forget that official recommendations can change; put in a call to your local fire service or state/territory authority for the latest word.
Alarm Placement and Upkeep
Do not put a carbon monoxide alarm in the same spot as you would a smoke alarm, follow the manufacturer on this. There are differences in how you position a unit on the wall versus the ceiling. And unless the maker says otherwise, keep it clear of curtains, furniture, grease, steam or dead-air pockets and any other obstructions.
In a multi-level or large home you may have to install more than one, with particular attention to the route from sleeping quarters to any fuel-burning equipment. Make sure to test them per the directions and put in new batteries as needed; the whole unit should be changed once its service life is up.
Some will buy an alarm and put it in a drawer and think they are done. A better course of action is to note down when it was put in and replaced in plain sight. Tenants should make a written record of any requests about gas appliances and without delay report any device that is missing, has expired or is making noise.
If You Suspect Exposure
An alarm or symptoms in the household are to be taken at face value until emergency personnel say different. It is wiser to get out of there than to go from room to room looking for the source and inhaling bad air in the process.
Evacuate without waiting to put out the alarm, see to your things or open the windows. You will not get fresh air until you are some distance from the suspected origin.
Emergency Protocol
- Get all in the house, pets included, into the open if it is safe to do so.
- For anything severe like chest pain, seizures, loss of consciousness, breathing trouble or confusion, dial 000.
- Should exposure be suspected, get medical advice in a hurry even after you are outside and feel an improvement; Healthdirect can be reached on 1800 022 222.
- Feeling better or a quiet alarm is no reason to go back inside.
- Nor is it time to use the appliance in question until a professional with the right licence has given it the once over.
Only attempt to pull an unconscious person from a contaminated area if the responders tell you it is ok to do so, or you risk collapsing too. Let the paramedics and clinicians know you suspect carbon monoxide, something the symptoms on their own might not indicate.
Heating in Winter
One can be practical about sensible habits and maintenance for safer heating in winter, instead of offering hollow advice from the comfort of a warm lounge room. Renters and those with energy bills to contend with are not always well served by impracticality.
Have the gasfitter come out before the run up to winter to look over the flue, ventilation and the appliance and how it interacts with exhaust fans. Put in for servicing and hold on to the invoice. This is not a job for a handyperson where licensed gas work is called for.
Opt for Lower-Risk Options
An electric blanket, reverse-cycle heating or an electric panel heater will put some heat in the room and no combustion gases to boot, provided the manufacturer has not put restrictions on it and the system is up to it. Be careful not to put too much demand on power boards, run a high-load heater off an extension lead that is not fit for purpose or put anything over a portable unit.
It is as important to warm the person as the environment. Put on layers of clothing, have bedding to suit the conditions and make use of insulated curtains and draught control which does not impede necessary vents. Even in the milder Australian winter, there is the matter of CO from running generators in the wake of cyclones and storms in the north. Whether it is wet or dry season is immaterial; engine exhaust belongs outdoors.
Frequently Asked Questions
When a household is sizing up its winter heating one comes across these questions, and with them some misconceptions that have the potential to make a cold evening a medical emergency. The following answers are meant to put those to rest.
If a tenancy rule, alarm or appliance is at issue then one should refer to the relevant authority in the state or territory and what the maker of the product says. Published advice is subject to change.
How Common Is Poisoning?
There is carbon monoxide poisoning in Australia but you will not find a national total for winter 2026 in the evidence we have been given. Some cases are non-specific or mild and pass unnoted and hospital figures do not tell the whole story. It is prudent to be preventative even if your home has had no such trouble.
Will Opening Windows Curb CO?
Fresh air can dilute what is in the house but relying on open windows is not a sure thing and will not render outdoor or defective equipment safe, given how building pressure and weather affect airflow. If exposure is suspected, get out and have the source looked at by a professional.
What is the Timeframe for Symptoms?
You cannot put a time on it. A lot depends on the individual’s health and vulnerability, the activity level and how long and how concentrated the CO is. Severe illness can come on in short order with high levels, lower exposure might be more insidious. Do not stand by for a few minutes before doing something about it.
Name Three Sources
In the home you have gas appliances that are not well vented or are faulty, charcoal or gas cooking done in an enclosed area and petrol or diesel engines like a generator. Then there are wood heaters, fireplaces, vehicles and other devices that burn fuel so the risk is not confined to three things.
Is a Smoke Alarm Enough for CO?
Not if it is a standard model, they are for smoke. For a carbon monoxide warning you need a unit that is marked as such, combination types will say they do both. But do not dispense with your smoke alarms when you put in CO ones, they serve different purposes.
A Winter Safety Routine
The way to manage the carbon monoxide risk in an Australian home this winter is to have it in hand before turning on the heater. Have your fuel-burning gear serviced, put the right alarms in place and see that ventilation is protected and outdoor equipment is kept where it should be. Evacuate at the first sign of exposure.
One might think a dangerous piece of equipment would announce itself by the way it looks or sounds. In fact CO gives no such warning and a perfectly normal appearing heater may be the cause. An annual routine is not as dramatic as an emergency, and for good reason.