Carbon monoxide alarms


What is carbon monoxide?

Carbon monoxide (CO) is a poisonous, flammable gas that is colourless, odourless, and tasteless, making it undetectable to human senses and only detectable via carbon monoxide alarms specially designed for it. It is detrimental to human health and also poses a fire risk.

Are carbon monoxide alarms legally required in all rental properties in Wales?

Yes, the installation of carbon monoxide alarms is compulsory under Section 5 of The Renting Homes (Fitness for Human Habitation) (Wales) Regulations 2022. One alarm is required in each room containing a gas appliance, an oil-fired combustion appliance or a solid fuel burning combustion appliance, which includes rooms with gas boilers and/or gas cookers.

Landlords are required to ensure each alarm remains in proper working order. The legislation doesn’t state how this should be done, but we would suggest that it includes regular testing and noting its expiry date, as an alarm that should have been replaced is unlikely to be deemed “in proper working order”. Carbon monoxide sensors are typically more fragile than those within smoke alarms, so usually need to be replaced more regularly.

Where should carbon monoxide alarms be placed?

The installer should follow the manufacturer’s instructions, which should be in accordance with British Standards. There is a belief that carbon monoxide alarms can’t be sited in humid rooms, but British Standards say they can be sited in a bathroom if the manufacturer advises their product is suitable for it.

Should carbon monoxide alarms be mains-wired, or can they be battery-operated type?

The legislation does not specify, so they can be of any type. We recommend mains-wired carbon monoxide alarms (combined fire & carbon monoxide alarms are available), as wall-mounted, battery-operated alarms require replacement (or at least their batteries do) after a certain length of time. Even if affixed to a wall, battery-operated alarms are usually easily detachable, making them more susceptible to being removed intentionally by contract holders, potentially compromising safety. When not affixed to a wall, they’ve been known to be shoved in drawers, which is a complete no-no.

Do carbon monoxide alarms need any certification?

By law, it is essential to ensure that carbon monoxide alarms are working during each period of occupation, however, they do not require a specific certificate or report proving this. The testing can be done by any competent person and should be recorded.

On most Gas Safety Certificate templates, there will be a section for carbon monoxide alarms where the engineer is prompted to tick whether they are present and working. Importantly, whilst these prompts ask the engineer to confirm that any carbon monoxide alarms present are in working order, it doesn’t prompt their confirmation that they are positioned in the correct room.

What are the consequences of not complying with legislation regarding carbon monoxide alarms?

Carbon monoxide cannot be seen, smelt nor tasted, but it can injure and kill quickly, so the worst-case scenario speaks for itself. Additionally, the legislation states that a property will be deemed unfit for human habitation if there isn’t a carbon monoxide alarm installed in a room which requires one. If a property is unfit for human habitation, a landlord will have a difficult job trying to charge rent.

How much does a carbon monoxide alarm cost?

The cost of a carbon monoxide alarm will depend on the type installed. As previously mentioned, we recommend mains-wired carbon monoxide alarms, which can be combined fire & carbon monoxide alarms. At CPS Homes, we have trusted connections with local, qualified engineers who can install carbon monoxide alarms quickly and professionally, all for a very reasonable cost due to the amount of work we issue to them. If you are a landlord in Cardiff and want to learn more about this benefit offered exclusively to our managed clients, get in touch with us today on 02920 668585 or lettings@cpshomes.co.uk.

Disclaimer: whilst we endeavour to keep the information on this page up-to-date, legislation, British Standards and general guidance can and do change, often without prior notice. As such, CPS Homes cannot guarantee with absolute certainty that the information on this page is fully up-to-date.

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