What are the carbon monoxide alarm requirements for landlords?
In England a landlord must fit a carbon monoxide alarm in any room used as living accommodation containing a fixed combustion appliance other than a gas cooker, and repair or replace one once told it is faulty. Wales, Scotland and Northern Ireland set different rules: the tables below give all four.
Reviewed by Jordan Valentine-Dunn, Gas Safe registered engineer · Portsmouth Gas Heating · Last reviewed September 2026
Four nations, four sets of words, and the differences are the kind that catch out anyone letting either side of a border. Wales has no cooker exclusion. Scotland applies its rule to every home rather than only rented ones. Northern Ireland brought its own rules in during 2024 and names a different British Standard. The tables below set out what each nation requires, who has to do it, and what happens if it is not done, with the source for every line.
Where must a landlord fit a carbon monoxide alarm?
In the room that holds the appliance, in all four nations, with the argument being over which rooms and which appliances count. England and Northern Ireland exclude gas cookers, Scotland excludes anything used solely for cooking, and Wales excludes nothing. Scotland and Northern Ireland also reach rooms a flue merely passes through. Find your nation in the first table for the duty itself, then the second for who carries it and what a breach costs.
| Nation and start date | Which rooms | Which appliances | Who the rules cover |
|---|---|---|---|
| England, 1 October 2022 | Any room used as living accommodation that contains the appliance. A hall or landing counts as a room, and a bathroom or lavatory counts as living accommodation. | Any fixed combustion appliance, whatever the fuel, other than a gas cooker. A gas cooker means any apparatus heated by gas and used for cooking food, so a gas fire or a solid fuel stove in a living room triggers the duty. | Private landlords and registered providers of social housing, including unlicensed HMOs. Excluded: shared accommodation with the landlord or their family, long leases, student halls, hotels and refuges, care homes, hospitals and hospices, low cost ownership homes. |
| Wales, 1 December 2022 | Each room of the dwelling that contains the appliance. Room here expressly includes a hall, landing or corridor. | Any gas appliance, oil-fired combustion appliance or solid fuel burning combustion appliance. There is no cooker exclusion, so a kitchen with a gas cooker needs an alarm. | Landlords under an occupation contract. Contracts that converted on 1 December 2022 got a 12 month run-in for smoke alarms but none for carbon monoxide alarms, which applied from the conversion date. |
| Scotland, 1 February 2022 | Every space containing a fixed combustion appliance, plus a bedroom or principal habitable room that a flue passes through. An appliance in a bathroom is covered by an alarm sited outside the room, 1 to 3 m away. | Any fixed combustion appliance except one used solely for cooking. A gas cooker or hob does not need one. | Every home, whatever the tenure, because the requirement sits in the tolerable standard. For a private let it also forms part of the repairing standard the landlord must meet. |
| Northern Ireland, 1 September 2024 for new tenancies and 1 December 2024 for the rest | Any room or circulation space of the dwelling containing a fixed combustion appliance or a flue. | Boilers, fires including open fires, heaters and stoves fuelled by solid fuel, oil or gas, but not a gas cooker or a gas oven. | Landlords under a private tenancy. The duty stays with the landlord even where a letting agent acts for them. |
| Nation | Who fits and maintains it | Penalty and enforcement | Source |
|---|---|---|---|
| England | The landlord fits it and has it checked to be in proper working order on the day a new tenancy begins. Once a tenant reports an alarm that is not working, the landlord repairs or replaces it as soon as reasonably practicable. | The local housing authority serves a remedial notice, then may arrange the work itself and impose a penalty charge of up to £5,000. GOV.UK's guidance says fines are applied per breach, so a house with two uncovered appliances is two breaches. | SI 2015/1693 regs 4, 5 and 8, as amended by SI 2022/707; GOV.UK landlord and tenant guidance. |
| Wales | The landlord, who must keep the alarm in repair and proper working order for the whole period of occupation. | No fixed fine. Where the landlord is not complying, the dwelling is treated as if it were unfit for human habitation, which puts the landlord in breach of the fitness duty carried by every occupation contract. | Renting Homes (Fitness for Human Habitation) (Wales) Regulations 2022, regs 5 and 7; gov.wales guidance for landlords. |
| Scotland | The owner. In a private let it is the landlord, as part of the repairing standard. | A tenant applies to the First-tier Tribunal (Housing and Property Chamber), which can make a repairing standard enforcement order and a rent relief order restricting the rent until the work is done. Failing to comply with the order without reasonable excuse is an offence, fine up to level 3 on the standard scale, £1,000. | Tolerable standard guidance chapter 17; gov.scot carbon monoxide alarms in private rented properties; Housing (Scotland) Act 2006 s28. |
| Northern Ireland | The landlord. Each alarm must be in proper working order at the beginning of every new tenancy, replaced when the landlord is told it is faulty, and replaced before the manufacturer's stated expiry date. | Failing to keep sufficient alarms in repair and proper working order is an offence under article 11B(4) of the Private Tenancies (Northern Ireland) Order 2006. On conviction the fine can reach level 4 on the standard scale, £2,500. | Smoke, Heat and Carbon Monoxide Alarms for Private Tenancies Regulations (Northern Ireland) 2024, reg 3; Department for Communities guidance notes. |
Check the nation the property sits in, not the one you live in. Two identical flats with identical boilers, one in Chester and one in Wrexham, carry different duties in the kitchen and a different consequence for getting it wrong. Fitting an alarm in every room with any gas, oil or solid fuel appliance satisfies all four nations at once, and nothing in any of the four rules stops you going further than its minimum.
Does a gas cooker need a carbon monoxide alarm?
In Wales, yes. In England, Scotland and Northern Ireland, no. England's regulation says fixed combustion appliance other than a gas cooker, and the guidance defines a gas cooker as any apparatus heated by gas and used for cooking food. Northern Ireland's regulations exclude a gas cooker or a gas oven by name. Scotland excludes any appliance used solely for cooking, and its guidance says plainly that a gas cooker or hob does not need a detector. The Welsh regulation lists a gas appliance with no carve-out at all, so a kitchen with a gas cooker in Cardiff needs an alarm that the same kitchen in Carlisle does not. This is the single most common cross-border mistake, and the appliance is identical in both.
Where should the alarm go in the room?
Between 1 and 3 metres from the appliance, out of dead air, and away from anything that moves air past it. That much every source agrees on. The height is where they part company: the England landlord booklet says head height on a wall or shelf, while the Scottish guidance and the manufacturers' summaries of BS EN 50292 put a ceiling-mounted alarm at least 300 mm from any wall or a wall-mounted one at least 150 mm below the ceiling and higher than any door or window. All of them defer to the alarm's own instructions, which is the tie-breaker on the day.
| Placement point | What the guidance says | Whose guidance |
|---|---|---|
| Distance from the appliance | 1 to 3 m from the appliance or any other potential source of carbon monoxide. | GOV.UK booklet for landlords; gov.scot; Aico, summarising BS EN 50292. |
| Mounted on the ceiling | At least 300 mm from any wall, light fitting or obstruction, which keeps it out of the dead air that collects in a corner. | gov.scot tolerable standard guidance; Aico. |
| Mounted on a wall | At least 150 mm below the ceiling and higher than any door or window in the room. | gov.scot tolerable standard guidance. |
| At head height | At head height, on a wall or a shelf. This is the England guidance's wording, and it sits lower than the wall position above. | GOV.UK booklet for landlords. |
| Appliance in a cupboard or boiler room | Put the alarm on the ceiling just outside the confined space, still 1 to 3 m from the appliance. | Aico, summarising BS EN 50292; gov.scot, which treats an appliance in a bathroom the same way. |
| A room with no appliance in it | At breathing height, and near bed head height in a bedroom. | Aico, summarising BS EN 50292. |
| Places it must not go | In an enclosed space such as a cupboard or behind a curtain, next to a door or window, next to an extractor fan, next to an air vent or similar opening, directly above a sink, or in a damp and humid location. | gov.scot, carbon monoxide alarms in private rented properties. |
| Temperature range | Not where the temperature falls below -10 °C or rises above 40 °C, unless the alarm is designed for those conditions. | gov.scot, carbon monoxide alarms in private rented properties. |
Scotland asks for one more alarm than the others: where a flue passes through a bedroom or the principal habitable room, that room gets its own detector even though the appliance is elsewhere. Northern Ireland's regulation reaches the same case by covering any room or circulation space containing a flue. If you let in either nation, walk the flue route as well as the appliance list.
What kind of carbon monoxide alarm should you buy?
One marked BS EN 50291 with a sealed battery that lasts the life of the unit. None of the four nations tells you to hard-wire it: England's guidance says the regulations do not stipulate mains powered or battery powered, and then recommends sealed-for-life batteries over replaceable ones. Scotland goes further and requires that a battery-powered detector has a battery designed to operate for the working life of the detector, with a device that warns when that life is nearly up. Working lives of 7 to 10 years are what the sealed units on sale carry.
| Marking on the box | What it covers | What it means for a rented home |
|---|---|---|
| BS EN 50291-1 | Test methods and performance requirements for carbon monoxide detection apparatus in domestic premises. | The standard a household alarm is built and tested to. This is the one to look for. GOV.UK's landlord guidance asks for alarms compliant with it, writing it as BS 50291. |
| BS EN 50291-2 | The same performance requirements for recreational vehicles, boats and similar, with extra testing for movement and vibration. | Not what a house needs. It matters if you also let a static caravan or a houseboat, where the Boat Safety Scheme asks for part 2. |
| BS EN 50292 | A guide to the selection, installation, use and maintenance of alarms. Detectors are not manufactured to it, they are installed to it. | This is where the siting rules in the table above come from. Northern Ireland's 2024 regulations name it directly as the standard alarms must comply with. |
| Kitemark or equivalent approval mark | An independent approval mark shown alongside the standard's number. | Public carbon monoxide safety advice asks for both the BS EN 50291 marking and a Kitemark or equivalent mark. An unbranded alarm bought from a marketplace listing often carries neither. |
| Sealed for the working life | A battery designed to run for the whole working life of the alarm, with an end-of-life warning. | Scotland requires it of battery alarms; England's guidance calls it the better option. It also removes the argument about whose job the batteries are. |
Who tests the alarm once the tenancy has started?
The landlord, on day one
England and Northern Ireland both require checks to confirm each alarm is in proper working order on the day a new tenancy begins. In England a new tenancy means an agreement starting on or after 1 October 2022 that is not a renewal of a previous one. There is no annual retest written into either rule, so day one is the point the duty bites.
The tenant, in between
England's guidance tells tenants to test alarms regularly, replace the batteries where the alarm takes replaceable ones, and report it to the landlord if the alarm still does not work. That is the trigger for the landlord's repair duty, so the handover conversation is worth doing properly: show where each alarm is, show the test button, and put the symptoms of carbon monoxide poisoning in writing alongside 0800 111 999.
The landlord again, once told
In England the alarm must be repaired or replaced as soon as reasonably practicable after a report that it is not working. In Northern Ireland the landlord must replace it when told it is faulty and also before the manufacturer's stated expiry date, which makes the printed end-of-life date part of the duty rather than good practice.
Everyone, at end of life
The date is printed on the casing and the alarm will chirp its own end-of-life warning if it meets the Scottish requirement. Write the replacement date into the property record the day you fit it, because a sealed 10 year alarm outlives most tenancies and nobody remembers it otherwise.
What does the gas engineer record about the alarm?
Nothing that the law requires. HSE sets out what a landlord gas safety record must contain, and carbon monoxide alarms are not on the list. What must be recorded is this:
- A description of and the location of each appliance or flue checked.
- The name, registration number and signature of the individual carrying out the check.
- The date on which the appliance or flue was checked.
- The address of the property at which the appliance or flue is installed.
- The name and address of the landlord, or their agent where appropriate.
- Any safety-related defect identified and any remedial action taken.
- Confirmation of the examination required by regulation 26(9) of the Gas Safety (Installation and Use) Regulations 1998.
So the alarm duty and the gas safety check are two separate obligations with two separate legal homes, and a current gas safety record is not evidence that the alarms comply. In practice the annual visit is the sensible moment to look at them, because an engineer is already standing next to every appliance on the list, and many will note the alarm's presence and function in the record's comments. Treat that note as a favour rather than a legal particular, and keep your own evidence: the make and model, the room, the date fitted and the end-of-life date.
What is the penalty for not fitting a carbon monoxide alarm?
England: up to £5,000 per breach
Where a local housing authority has reasonable grounds to believe a landlord is in breach, it must serve a remedial notice within 21 days of that decision, and the notice requires the work within 28 days beginning with the day it is served. A landlord may make written representations within 28 days, which suspends the notice until the authority confirms, amends or withdraws it, and the authority has 7 days after that period ends to do so or the notice falls away. If the work is still not done the authority arranges it and may impose a penalty charge, which must not exceed £5,000 and which GOV.UK's guidance says is applied per breach. There is a right to ask the authority to review the charge, and then a right of appeal.
Wales: the home is treated as unfit
There is no penalty charge. The regulation says a dwelling is to be treated as unfit for human habitation at a time when the landlord is not complying, which lands the landlord in breach of the fitness duty that sits in every occupation contract and opens the remedies that follow from that.
Scotland: a tribunal order, then a fine
A tenant applies to the First-tier Tribunal (Housing and Property Chamber) for a determination on the repairing standard. The tribunal can issue a repairing standard enforcement order and a rent relief order restricting the rent until the order is complied with. Failing to comply without reasonable excuse is a criminal offence carrying a fine up to level 3 on the standard scale, £1,000, and re-letting the house while the order is in force is a separate offence at the same level.
Northern Ireland: up to £2,500
Failing to keep sufficient alarms in repair and proper working order is an offence under article 11B(4) of the Private Tenancies (Northern Ireland) Order 2006. The Department for Communities guidance puts the fine on conviction at no more than level 4 on the standard scale, which is £2,500.
What should you do if the carbon monoxide alarm sounds?
Get outside
Everyone into fresh air, and stay out. The NHS is explicit that you should not go back into the affected building until you have had advice.
Turn the appliance off if you safely can
The NHS advice is to stop using the appliance you think might be producing carbon monoxide, if you can do so. Do not start hunting for the fault yourself.
Call 0800 111 999
The National Gas Emergency Service line is free and staffed around the clock, and the NHS names it as the number to call when you think a gas appliance is leaking carbon monoxide.
Get medical advice
Call NHS 111 if anyone has symptoms. Call 999 or go to A&E for difficulty breathing, sudden confusion, loss of consciousness, weakness, or chest and muscle pain. The symptoms to watch for are headache, dizziness, feeling sick or being sick, feeling weak, tiredness and confusion, chest and muscle pain, shortness of breath and loss of vision, and the telling pattern is symptoms that ease when everyone leaves the building.
Do not use the appliance again until it has been checked
A Gas Safe registered engineer has to examine the appliance and its flue before it goes back into service, and the visit is the point at which any defect gets recorded and put right.
Two dates decide whether a property stays compliant: the gas safety renewal and the alarm's end-of-life. Manifold tracks the first for every property and chases it automatically, keeps each certificate in the landlord portal, and gives you somewhere to record what the engineer noted about the alarms while they were on site.
Read next
If an alarm sounds or anyone has symptoms, treat it as an emergency: get everyone into fresh air, turn the appliance off if you safely can, and call the National Gas Emergency Service on 0800 111 999. This page is general guidance, not legal advice, and the rules differ across the four UK nations. Only a Gas Safe registered engineer can carry out the annual gas safety check.
Frequently asked
Sources
- Legislation.gov.uk, Smoke and Carbon Monoxide Alarm (England) Regulations 2015, regulation 4 (landlord duties)
- Legislation.gov.uk, Smoke and Carbon Monoxide Alarm (England) Regulations 2015, regulation 5 (remedial notices)
- Legislation.gov.uk, Smoke and Carbon Monoxide Alarm (England) Regulations 2015, regulation 8 (penalty charge, £5,000 maximum)
- Legislation.gov.uk, Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022 (in force 1 October 2022)
- GOV.UK, Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022: guidance for landlords and tenants
- Legislation.gov.uk, Renting Homes (Fitness for Human Habitation) (Wales) Regulations 2022, regulation 5
- GOV.WALES, Fitness of homes for human habitation: guidance for landlords
- GOV.SCOT, Satisfactory fire and carbon monoxide detection: tolerable standard guidance, chapter 17
- GOV.SCOT, Carbon monoxide alarms in private rented properties: guidance (siting figures)
- mygov.scot, Repairs and maintenance as a private landlord: the tolerable standard
- Legislation.gov.uk, Housing (Scotland) Act 2006, section 28 (offence, level 3 fine)
- Legislation.gov.uk, Smoke, Heat and Carbon Monoxide Alarms for Private Tenancies Regulations (Northern Ireland) 2024, regulation 3
- Department for Communities, Smoke, Heat and Carbon Monoxide Alarms for Private Tenancies Regulations (NI) 2024: guidance notes
- Aico, alarm siting (carbon monoxide alarm positions, summarising BS EN 50292)
- Safelincs, British Standards for CO alarms (BS EN 50291-1, 50291-2 and 50292 explained)
- HSE, gas safety check records and what to keep
- HSE, gas safety for landlords and letting agents
- NHS, carbon monoxide poisoning (symptoms, what to do, 0800 111 999)
Related guides
Last reviewed September 2026. This guide is general information, not legal or safety advice, gas safety work must be carried out by an appropriately Gas Safe registered engineer. Rules can change, so check the linked official sources for the current position.