The importance of having carbon monoxide alarms in a property

Understanding how carbon monoxide is produced, where it poses the highest risk, and where alarms are legally required across the UK can help improve both safety and compliance. Here’s what to highlight in your conversations with customers.

What is Carbon Monoxide and why is it dangerous?

Carbon monoxide (CO) is produced when fuels like gas, oil, wood, or coal burn incompletely. It can quickly build up to lethal levels without any visible or detectable signs.

• Common sources of CO in the home include:
• Gas boilers and fires
• Log burners and open fires
• Flues and chimneys
• Portable heaters and BBQs used indoors

Symptoms of CO poisoning mimic flu, including headaches, nausea, confusion and—at high exposure—can lead to unconsciousness or death.

Where are CO alarms required in the UK?

Carbon monoxide alarm legislation varies depending on the location. In England and Wales, CO alarms must be installed in rented homes with solid fuel appliances, such as log burners or coal fires. In Scotland, CO alarms are legally required in any room that contains a fixed combustion appliance or flue, which includes gas boilers. In Northern Ireland, alarms are required for solid fuel appliances, and although not legally required for gas yet, their use is still strongly recommended.

The safest and most consistent advice is to fit a carbon monoxide alarm near every fuel-burning appliance—regardless of the region or tenancy status.

Placement advice for optimal protection

To meet BS EN 50291-1 standards:

• Install 1–3 metres from the appliance
• Mount at breathing height (head height in living spaces, sleeping height in bedrooms)
• Wall or shelf mount—not above fireplaces or near extractor fans, windows, or vents
• In multi-level homes, install one on each floor with a fuel appliance

For homes with multiple fuel-burning appliances, interlinked CO alarms are recommended

Maintenance tips and alarm lifespan

Most CO alarms have a lifespan of 7 to 10 years, depending on the model. For reduced maintenance and greater reliability, recommend sealed battery units with a built-in 10-year life. Encourage clients to test alarms monthly and replace them at the end of their service life, as printed on the back of the unit.

Choosing tamper-proof models is also a good way to avoid accidental removal or damage—particularly in rental properties or holiday lets.

Who is most at risk of carbon monoxide poisoning?

CO can affect anyone, but some groups are especially vulnerable:

• Babies and young children
• Older adults
• People with heart or respiratory conditions
• Renters in older or poorly maintained housing
• Holidaymakers using gas stoves or BBQs in tents or caravans

If you manage housing stock or install alarms professionally, these are the people your decisions help protect.