Carbon monoxide poisoning is a silent but deadly risk in many UK homes. With no smell, taste or colour, carbon monoxide (CO) is often called the “invisible killer”. It can leak from common household appliances and affect people before they even realise something’s wrong.
In this article, we’ll explain what carbon monoxide poisoning is, how to spot the signs, how to prevent it, and what to do if you think there’s a leak. Whether you live in a flat in London or a cottage in the countryside, this is something that affects us all.
What Is Carbon Monoxide?
Carbon monoxide is a toxic gas produced when fuels like gas, wood, coal or oil don’t burn completely. It can come from everyday appliances such as:
- Gas boilers
- Cookers and ovens
- Fires (wood-burning or coal)
- Portable heaters
- Chimneys or flues that are blocked or poorly maintained
If these aren’t fitted or looked after properly, carbon monoxide can leak into your home without any warning.
Book your gas safety check today.
Don’t leave it to chance.
Why Is Carbon Monoxide Dangerous?
The scary thing about CO is how quickly it can make you ill—or worse. It stops your body from carrying oxygen, which can lead to serious health problems or even death.
Symptoms often seem like a cold or flu at first, which is why it’s often missed. The main signs include:
- Headaches
- Dizziness
- Nausea or vomiting
- Tiredness
- Confusion
- Chest or stomach pain
- Difficulty breathing
If everyone in your home starts feeling unwell at the same time, especially when indoors, that’s a big red flag.
What to Do if You Suspect Carbon Monoxide Poisoning
If you think there’s a carbon monoxide leak:
- Get fresh air immediately – open doors and windows.
- Turn off appliances – switch off gas or solid fuel devices.
- Leave the property – don’t stay inside to “wait and see”.
- Call emergency services – ring 999 and ask for the fire brigade if you suspect a serious leak.
- Seek medical attention – go to A&E or call 111 if you or anyone in your home is feeling unwell.
Do not re-enter your home until it’s been checked by professionals.
How to Prevent Carbon Monoxide Poisoning
The good news is, CO poisoning is largely preventable. Here’s how to keep your household safe:
Install a Carbon Monoxide Alarm
- A carbon monoxide detector is your first line of defence. Make sure it meets British Standards (BS EN 50291), and ideally has a loud alarm. Place one in each room with a fuel-burning appliance.
- Test it regularly and replace batteries when needed.
Service Appliances Annually
Get your boiler, cooker, fireplace and chimney serviced once a year by a Gas Safe registered engineer or a qualified heating specialist. Look for the Gas Safe Register logo.
Don’t Block Vents
Fresh air is crucial. Never cover air bricks or ventilation grilles, and keep chimneys and flues clear.
Be Cautious With Portable Heaters and BBQs
Never use outdoor appliances like barbecues or camping stoves indoors. They produce carbon monoxide even if there’s no flame.
Who’s Most at Risk?
Certain groups are more vulnerable to carbon monoxide poisoning, including:
- Babies and young children
- Elderly people
- Pregnant women
- People with heart or breathing conditions
If someone in your household falls into one of these groups, it’s especially important to be cautious.
Legal Responsibilities for Landlords in the UK
If you rent your home, your landlord has a legal duty to:
- Install carbon monoxide alarms in rooms with a solid fuel appliance
- Check alarms are in working order at the start of each tenancy
- Ensure annual gas safety checks are carried out by a Gas Safe engineer
Tenants should still test alarms regularly and report any faults or signs of a leak.
The Bottom Line
Carbon monoxide poisoning is a real threat in UK homes, but it’s one you can protect yourself against with a bit of know-how and simple steps.
Install alarms, get regular checks, and stay alert to the symptoms. By doing so, you’re not just protecting your property — you’re protecting lives.
FAQs
Yes, it can. While good ventilation helps reduce the risk, a faulty appliance can still release dangerous levels of carbon monoxide. Having proper ventilation is not a substitute for regular servicing or a working CO alarm.
It depends on the level of exposure. In high concentrations, symptoms can appear within minutes. With lower levels, it might take several hours of continuous exposure before you notice anything wrong. This makes early detection vital.
No. Carbon monoxide detectors only sense CO — not natural gas or LPG leaks. For gas leaks, you’ll need a separate gas detector. It’s best to have both types of alarm in homes using gas appliances.
Most alarms give off a loud, high-pitched beeping — different from a smoke alarm. If it goes off, don’t assume it’s a false alarm. Leave the house and get it checked immediately.
Yes, cases tend to rise in colder months when people use heating more often and keep windows closed. It’s also the time when many chimneys and flues are in use, which increases the risk if they’re not properly maintained.
They can. Pets may act unusually — become lethargic, struggle to breathe, or vomit. If your pet suddenly seems unwell indoors but perks up outside, it could be a warning sign of carbon monoxide.
No. It has no smell, no taste, and no colour. That’s what makes it so dangerous. People often don’t realise they’re being poisoned until symptoms become severe — or it’s too late.
You don’t need one in every room, but you should place alarms near every fuel-burning appliance and sleeping area. It’s also wise to have one on each floor of the house, especially near bedrooms.
Yes. Survivors of moderate to severe poisoning can suffer lasting effects such as memory problems, vision issues, mood changes, or damage to the heart and brain. Quick treatment is vital to reduce long-term harm.
It varies by provider and policy. Some insurance policies may cover damage or injury caused by a CO leak if the cause wasn’t due to negligence. It’s best to check the fine print or speak to your insurer directly.
Further Reading
What is the validity of a commercial gas certificate for businesses?
Is a gas certificate compulsory for a commercial property?
Everything you need to know about getting an LPG certificate in London
Boiler Service Near Me: Essential guide to boiler maintenance
Does a commercial property need a gas safety certificate?
What you need to know about catering commercial gas certificate that covers catering
Where can I get my LPG gas conversion certificate?
How much does an LPG certificate cost?
Commercial gas safety certificate
What you need to know about commercial gas safety certificate cost?
What certificate does a commercial landlord require for gas?
Commercial catering gas safety certificate law: What you need to know
How to Get the LPG Engineer – One That Issues LPG Gas Safety Certificates
Who is responsible for gas certificates in commercial properties?
