What Are the Rules on Carbon Monoxide (CO) Alarms in England?
Carbon monoxide (CO) is often called the silent killer; a colourless, odourless, and tasteless gas that can be deadly when inhaled. It’s produced when fuels such as gas, oil, wood, or coal do not burn completely.
To protect residents from this hidden danger, the UK Government introduced regulations requiring carbon monoxide alarms in all homes and rented properties where fuel-burning appliances are installed. Here’s what every homeowner, landlord, tenant, and business owner needs to know.
CO Alarm Rules for Homeowners
If you’re a homeowner in England, you must install a carbon monoxide alarm in every room that contains a fixed combustion appliance (other than a gas cooker).
This includes:
- Gas or oil boilers
- Gas or solid-fuel fires
- Wood-burning or multi-fuel stoves
It’s the homeowner’s responsibility to:
- Purchase and install CO alarms that meet British Standards (BS EN 50291).
- Test alarms regularly (monthly is best practice).
- Replace alarms according to the manufacturer’s recommended lifespan which is typically every 5 to 7 years.
Having a working CO alarm is not only a legal obligation in certain situations; it’s a vital safety measure for your household.
CO Alarm Rules for Landlords
Since October 2022, updated regulations require private and social landlords in England to:
- Install a CO alarm in every room with a fixed combustion appliance (excluding gas cookers).
- Test alarms on the first day of a new tenancy.
- Repair or replace faulty alarms promptly once a tenant reports a problem.
Failure to comply can result in civil penalties of up to £5,000. The aim is clear: ensure tenants are protected from the dangers of carbon monoxide throughout the duration of their tenancy.
CO Alarm Responsibilities for Tenants and Residents
Tenants also have responsibilities under the rules. Once the landlord has ensured alarms are correctly fitted and working at the start of the tenancy, tenants should:
- Test alarms regularly (at least once a month).
- Report any faults or low-battery warnings immediately.
- Never remove, cover, or disable an alarm even temporarily.
CO alarms are there for your safety. Treating them with care and checking them routinely could save lives.
What About Businesses and Workplaces?
For commercial buildings and workplaces, the rules fall under Health and Safety legislation rather than domestic housing law. Employers, building owners, and facility managers are responsible for assessing the risk of CO exposure and fitting alarms where combustion appliances are present.
For example, leisure centres, hotels, and office buildings with boilers, gas heaters, or plant rooms should have CO detection in place and tested as part of their planned maintenance schedule. Smart Heating EA Ltd can assist with this scheduling.
Who Fits CO Alarms and When?
CO alarms can be fitted by:
- A competent person (for battery or plug-in models), or
- A Gas Safe registered engineer when working on or servicing appliances.
It’s best practice to install alarms at head height, roughly 1–3 metres from the appliance, and in accordance with the manufacturer’s instructions.
Whenever Smart Heating EA Ltd engineers install or service a boiler or heating system, we also ensure CO alarm placement and operation are checked as part of our safety procedure.
What to Do if a CO Alarm Activates
If your carbon monoxide alarm sounds:
- Stop what you’re doing and act immediately.
- Turn off gas appliances (if safe to do so).
- Open doors and windows to ventilate the area.
- Leave the building immediately.
- Call the Gas Emergency Service on 0800 111 999 (for gas leaks) or 999 if anyone is unwell.
- Seek medical attention if you feel dizzy, nauseous, or confused as these could be symptoms of CO poisoning.
- Do not re-enter the property until it’s been declared safe.
Afterwards, arrange for a Gas Safe registered engineer to inspect and repair the faulty appliance or flue before switching anything back on.
Smart Heating EA Ltd: Committed to Your Safety
At Smart Heating EA Ltd, our engineers are trained to prioritise safety at every step. From Gas Safe registration to ongoing professional development, we make sure every installation and service visit protects your property and the people inside it.
We check CO alarm operation and placement as part of every boiler service or system maintenance visit, ensuring your heating setup complies with current safety regulations. Your safety is never an afterthought, it’s built into everything we do.
Protect Your Home or Business Today
Don’t wait for an emergency to discover your CO alarm isn’t working. Book a professional heating service with Smart Heating EA Ltd to make sure your carbon monoxide protection is up to standard.
Call us today or contact us online to arrange your next service visit.
Smart Heating EA Ltd — Safety First. Expertise Always.






