SGN published figures on 17 November 2025 showing that 26% of carbon monoxide (CO) call-outs attended by its engineers are considered false alarms linked to battery or alarm failure1. The data comes from the Carbon Monoxide Research and Analytics (CORA) platform, which is supported by Great Britain's Gas Distribution Networks, including SGN1. The company released the statistics during Carbon Monoxide Awareness Week1.
For 2024, SGN attended 21,603 CO incidents across its Southern network, of which 16,774, or 77%, were either suspected or confirmed to have CO present1. In Scotland over the same period, SGN attended 10,341 CO incidents, of which 6,774, or 65%, were either suspected or confirmed to have CO present1. The statistics run up to and including 31 December 20241.
The figures follow SGN's summer disclosure that analysis of households with digital CO alarms showed 95% had not checked their devices in 20241. Dan Edwards, SGN Social Impact Programme Lead, said:
"It's deeply worrying that so many people aren't testing their carbon monoxide alarms. Carbon monoxide is known as the 'silent killer' for a reason - it's invisible, it's odourless, and it can be deadly. Having a CO alarm is essential, but it's just as important to test it regularly to make sure it's working correctly and helping to keep your household safe."
SGN said CO symptoms including headaches, nausea, dizziness and breathlessness can be mistaken for other illnesses such as a cold, a hangover or food poisoning, and that the gas cannot be seen, smelt or heard and has no taste1. It said a smoke alarm is not a carbon monoxide alarm, and that CO alarms should comply with safety standard BS EN 502911. SGN also said appliances should be fitted and checked annually by a Gas Safe registered engineer1. The company said its alarms carry an expiry date, normally printed on the alarm itself1.
| Network | CO incidents attended, 2024 | Suspected or confirmed CO present |
|---|---|---|
| Southern | 21,603 | 16,774 (77%) |
| Scotland | 10,341 | 6,774 (65%) |
Why it matters for households
A CO alarm that has failed, or whose battery has gone flat, gives no warning of a gas that has no colour, smell or taste. On SGN's figures, roughly one in four call-outs it attended involved an alarm or battery problem rather than a confirmed or suspected presence of CO, which means the warning device itself was the point of failure in those homes1. The separate finding that 95% of households with digital CO alarms had not checked them in 2024 points to a gap between owning a detector and knowing it works1. For a household's energy independence, a working alarm is part of the safety case for running gas appliances at all; carbon monoxide safety and detector placement both bear on whether a device will actually sound.
What happens next
SGN said it is urging households to test their CO alarms ahead of the winter school holidays1. No further dated steps were reported1.