Carbon Monoxide and Smoke Alarms: What UK Law Now Requires and Which Alarm to Buy

The rules around alarms in UK homes changed significantly in October 2022. The Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022 extended mandatory CO alarm requirements to all rental properties with any fixed combustion appliance — not just solid fuel. If you're a landlord, letting agent, gas engineer, or electrician working on residential properties, this guide sets out the current legal position and the alarm options in stock at APM.

What the Law Now Requires (England, from 1 October 2022)

Under the Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022:

• CO alarms are now required in every room with a fixed combustion appliance — this includes gas boilers, gas fires, gas cookers, oil boilers, and solid fuel appliances. Previously, CO alarms were only mandated for solid fuel appliances in the private rented sector.
• Smoke alarms are required on every storey of a rental property (unchanged, but now also applies to social housing).
• All alarms must be in working order at the start of a new tenancy. Landlords are responsible for testing and remedying any defect reported by a tenant.
• Local authorities can issue remedial notices and fines of up to £5,000 for non-compliance.

Owner-occupied homes: The regulations apply to rental properties. Owner-occupiers are not legally required to install CO alarms under this legislation, but Building Regulations Part J requires CO detection wherever a new or replacement boiler is installed. In practice, any Gas Safe engineer fitting a boiler should be recommending (and many will insist on fitting) a CO alarm as standard.

Scotland and Wales have separate regulations — CO alarm requirements differ. This guide covers England.

CO Alarm Placement: Where to Install

• In every room containing a gas boiler, gas fire, or gas cooker — so most properties need at least a kitchen CO alarm (for the boiler or cooker) and a living room alarm if there's a gas fire
• At breathing height (approximately 1–2 metres from the floor) — CO distributes evenly in air, unlike smoke which rises
• Not directly above a combustion appliance — at least 1 metre away from the appliance itself
• Not in areas of high humidity (bathrooms, outside) unless the unit is rated for this
• Audible from sleeping areas — or fit additional alarms in bedrooms if the property layout doesn't allow this

Carbon Monoxide Alarms in Stock at APM

• Arctic Hayes SleepSafe 10-Year Sealed Battery CO Alarm — 10-year sealed battery means no battery changes for the life of the alarm. The most cost-effective compliant option for landlord portfolios. EN 50291-1 approved.
• Kidde 7DCOC Digital CO Alarm, 10-Year Sensor — digital display showing current CO level in ppm (parts per million), peak level recall, and end-of-life warning. The professional's choice: the display lets engineers confirm the alarm is reading correctly and show tenants the current level at inspection.
• Daewoo CO Alarm, 7-Year Life — reliable battery-powered alarm with test/reset button. Good mid-range option where the digital display of the Kidde isn't required.
• Honeywell Home R200C-1 Standalone CO Alarm — Honeywell's domestic CO alarm. Battery powered, sealed unit, LED status indicator.
• Kidde 2030DCR 10-Year Life CO Alarm — compact format, 10-year battery life, loud 85dB alarm. Suitable for properties where space near the appliance is limited.
• FireAngel Spec FS1326-T 10-Year CO Alarm — FireAngel's professional range, designed for the rental and social housing market. Tamper-resistant, sealed 10-year battery.
• Hispec RF Interlinked CO Alarm, Battery — radio-frequency interlinked: when one alarm triggers, all linked alarms in the property sound. Essential for larger properties, HMOs, and any property where a single alarm may not be audible from all bedrooms.

Smoke Alarms: Types and When to Use Each

Three types of smoke and fire detection are relevant to residential installations:

Optical Smoke Alarms

Optical alarms use an infrared beam inside the sensor chamber. Smoke particles scatter the beam and trigger the alarm. They respond well to slow, smouldering fires (furniture, bedding) and are less prone to nuisance alarms from cooking fumes than ionisation types. Recommended for hallways, living rooms, and bedrooms.

• Hispec RF Interlinked Optical Smoke Alarm, Battery — radio-frequency interlinked with other Hispec RF alarms. Battery powered, suitable for properties where mains wiring to every alarm is not practical.
• Axiom ALRFSM Mains Optical Smoke Alarm with Battery Backup, RF — mains powered with battery backup and RF interlink. Grade D2 to BS 5839-6, the recommended specification for new residential builds and full renovations.

Heat Alarms

Heat alarms respond to temperature rise rather than smoke particles. They do not false-alarm from cooking fumes, making them the correct choice for kitchens. They are not a substitute for smoke alarms in other rooms — they respond later in a fire event.

• Hispec Heat Alarm, 9V Battery — standalone heat alarm for kitchens. 58°C fixed temperature trigger.
• Hispec RF Interlinked Heat Alarm, Battery — RF interlinked version for full system coverage including the kitchen.
• Axiom ALRFHM Mains Heat Alarm with Battery Backup, RF — mains with battery backup, RF interlinked. Grade D2 kitchen specification.

Alarm Grades: What BS 5839-6 Requires

BS 5839-6 classifies domestic fire detection systems by grade:

For rental properties, Grade F1 (sealed 10-year battery) is the practical standard — it removes the battery replacement issue that leads to alarms being disabled by tenants. For any new build or major renovation, Grade D2 (mains with backup, interlinked) is correct.

What Gas Engineers Should Know

Under current Gas Safe guidance, a CO alarm should be fitted whenever:

• A new gas appliance is installed
• An existing appliance is serviced and no CO alarm is present
• The existing CO alarm is past its end-of-life date (check the label)

Fitting a CO alarm takes two minutes. At – per unit, not fitting one on a boiler service is a liability risk that isn't worth taking. Keep a stock of Arctic Hayes SleepSafe or Kidde 10-year units in the van.

All CO alarms and smoke detectors listed are in stock for same-day collection from our Acton trade counter.

APM Plumbing & Electrical | 24 Western Avenue, Acton, London W3 7TZ | 020 8702 8080 | apmi.uk