Requirements for Fire Detection Systems in HMOs

What is an HMO?

HMOs are typically large houses that have been converted into flats or bedsits, such as student housing. ‘Houses in multiple occupation’ are defined by gov.uk as follows:

Your home is a house in multiple occupation (HMO) if both of the following apply:

  • at least 3 tenants live there, forming more than 1 household
  • you share toilet, bathroom or kitchen facilities with other tenants

It is important to note that the requirements for sheltered housing, such as supported living facilities, and self-catered rentals, such as holiday cottages are different, and not covered in this blog.

Kitchen facilities are often shared in HMOs
Shared kitchen spaces are a fire risk in HMOs

What grade of smoke alarm system is required for HMOs?

Within most HMOs, there are several acceptable options available for compliance with the Standard, depending on its size and configuration. 

The first option is to have Grade A fire alarm system installed throughout the building. This type of system consists of a conventional or addressable fire alarm panel, and then fire alarm detectors, call points, sounders and beacons are specified according to the layout and requirements of the property and manufactured to BS EN 54. It also requires a power supply to BS EN 54-4, and installation to BS 5839 Part 1.

However, in most cases, this level of coverage is not a requirement. In some small HMOs, for example, it may be acceptable to install a Grade D1 system. This is defined as a system incorporating one or more interlinked mains-powered smoke alarms (and heat alarms if required), each with an integral stand-by supply. They can be hardwire-interlinked or radio-interlinked, meaning that fire alarm panels are not required. The stand-by supply must be tamper-proof and last the full life of the alarm.

The final option, suitable for many medium and even large HMOs, is a mixed system. This involves the installation of Grade A components in communal areas, and any other high-risk areas identified by the risk assessment. Elsewhere in the premises, a separate Grade D1 system can be installed. This has become the preference, as it is likely to reduce the impact of nuisance alarms from individual flats on other occupants.

Ei Electronics and Kidde offer both RF and wired mains powered alarm systems as well as a range of accessories that can help you to test, locate and hush alarms easily. For more guidance about the alarm grade system, visit our help guide.

Mains Powered Smoke Alarms with Lithium Back-up Ei3000 Series
Mains Powered Smoke Alarms with Lithium Back-up Ei3000 Series
  • Available in Optical, Heat, Combined Optical & Heat, and Combined Heat & CO
  • Mains powered alarms with sealed lithium back-up battery
  • AudioLINK technology fitted as standard
  • Interlinks with up to 12 compatible devices
  • Compatible with Ei3000MRF SmartLINK Module for radio-interlinking
  • Suitable for BS 5839-6: 2019 Grade D1 installations
  • Also suitable for both the Welsh and Scottish 2022 legislation
£44.99 ex VAT
£53.99 inc VAT
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Fire detection categories

The coverage within the building by the detection system is divided into three distinct categories. These are described with the following codes:

LD1 (highest level of coverage): Covers all circulation spaces that form part of escape routes plus all rooms in which a fire could start

LD2 (middle level of coverage): Covers all circulation spaces that form part of escape routes plus all rooms and areas that present a high fire risk to occupants

LD3 (lowest level of coverage): Covers circulation spaces that form part of the escape routes

Diagram showing levels of fire detection systems in HMOs

Any room which a building user must pass through, from another, in order to exit the premises would need detectors installed to satisfy these Categories. For example, if all rooms in a bungalow open onto a hallway which leads outside, only the hallway is considered a circulation space forming part of the escape route; if the only exit from the kitchen is into the dining room which then opens onto a hallway, the dining room would also need a detector under LD3 minimum protection as it is part of the escape route.

What category of fire detection is required within my HMO?

Different levels of coverage are needed in different areas of the building due to the risk of fire. This includes different Grades of fire detection system, as well as different configurations of components. For example, communal areas in HMOs are required to have Grade A systems, as they have particularly high levels of risk. This is due to the shared, and therefore often neglected responsibility for safety and housekeeping in HMOs. Moreover, the exact installation requirements within your HMO will depend upon the configuration and size of the premises. For more advice for landlords about fire safety in HMO’s, visit our help guide.

Messy kitchens are a health risk, and a fire hazard.
Responsibility for housekeeping can be neglected in HMOs. This is a fire risk,

Minimum levels of requirements for fire detection systems in HMOs:

The following is general guidance on the minimum levels of installation required in different scenarios.

One or two storey HMOs, where the area of each floor is less than 200sqm:

A Grade D1, category LD1 configuration should be installed in a new, or materially altered HMO. In an existing premises of this size, category LD2 is acceptable if it is already installed, but an LD3 system must be upgraded to comply with the Standard.

Areas within HMOs with more than 3 floors, or where the area of at least one floor is greater than 200sqm

Individual, one-room dwellings, with or without cooking facilities:

A Grade D1, category LD1 configuration should be installed. This is required in a new and existing HMO premises.

Individual dwellings comprising two or more rooms:

A Grade D1, category LD2 configuration should be installed. This is required in a new and existing HMO premises.

Communal areas

A Grade A, category LD2 configuration should be installed. This is required in a new and existing HMO premises.

Suitable Fire Detection Systems in HMOs

Always ensure that a comprehensive fire risk assessment has been carried out in your property by a competent person, to determine the risks specific to your premises. This is essential to protect the occupants, particularly as many tenants of HMOs are young and / or vulnerable renters. The Responsible Person for the building may be prosecuted if they cannot demonstrate that they have made every reasonable effort to comply with fire safety requirements enforced by their local council, particularly if a fire breaks out. Compliance with the Standards is the best way to ensure that this compliance can be achieved and evidenced.  

For additional guidance, please visit our Smoke Alarm Help and Information and BS 5839 summary page.

Hushing Interlinked Smoke Alarms

Interlinked smoke alarms are becoming more and more popular as they quickly alert you to the event of a fire across larger houses, where there is a risk that you might not hear an alarm going off in the kitchen when you are, for example, in a bedroom upstairs.

Whether connected to each other with wire or wirelessly interlinked through radio frequency, interlinked smoke alarms allow you to connect multiple units – including different types of detectors – which will all sound at the same time when a single alarm detects a potential fire. The heat alarm in the kitchen, the ionisation alarm in your home office, and the specialist strobe and vibration alarm in your elderly parents’ bedroom, for example, will all go off at the same time, if just one alarm is triggered by fire.

Most of us are familiar with the test button on smoke alarms which allows residents to test their alarms regularly, to ensure the components are working and the power supply, whether battery or mains power, is working. On top of this, however, many alarms have a “hush” button which allows you to silence an alarm that has gone off, for example, due to burnt toast.

So how do hush buttons work when you have several interlinked alarms?

It’s easy to assume that, as they are all connected, hushing one alarm will silence all of them, but it is equally logical that only the unit on which you pressed the hush button should be silenced – after all, you don’t want people to assume it was a false alarm if there really is a fire raging downstairs.

Interestingly, not all interconnecting smoke alarms hush in the same way. Here is an overview explaining the different approaches employed by the three main smoke alarm manufacturers in the UK.

Kidde Slick Wireless Smoke and Heat AlarmsFor Kidde smoke alarms, the originating alarm (the unit which detected a potential fire and triggered all of your units) will have its warning light flash faster than all other units while the alarm is sounding – enabling you to identify the smoke alarm that caused the alarm. Pressing the hush button on ANY unit will silence the ENTIRE network.

Ei160e Series Smoke and Heat AlarmsIf you have interlinking Ei Electronics smoke alarms, only the originating unit’s hush button will be able to silence the ENTIRE network. The other units in the circuit can be individually silenced. To identify the originating unit you need to look for the alarm whose warning light is flashing every second, compared to every 40 or so seconds on the other units.

FireAngel WST600 Series Radio-Interlinked Smoke and Heat AlarmsFireAngel smoke alarms, however, deploy an improved silencing protocol. If you hush the originating smoke alarm then, as with the other brands, ALL connected units will be silenced. However, if you hush any other unit, the ORIGINATING alarm will continue to sound but ALL OTHER units will be silenced. This allows you to quickly identify the originating alarm which is very helpful both in case of a false alarm or a real emergency.

If you require support selecting the best smoke alarm system for yourself, please contact the friendly Safelincs support team either by emailing support@safelincs.co.uk or by ringing 0800 612 6537

Kidde stops smoke alarms beeping at night

Kidde Safety EuropeSmoke alarms have reduced the number of deaths and injuries related to fire in the UK dramatically over the last decades and are now an essential must-have in every household.
All these millions of smoke alarms, however, rely on batteries in one way or the other. Mains powered smoke alarms require a backup battery in case the mains power supply fails and battery powered smoke alarms use them, as the name suggests, as main source of power. When the battery comes to the end of its life the smoke alarm emits a regular beeping sound for several weeks before the battery finally expires. This gives the owner sufficient time to replace the battery.
As the voltage of a battery drops at lower temperatures, the first low battery warnings are usually emitted at night, when our houses are at the coolest, especially in autumn and winter. This can be very annoying as you are woken up in the middle of the night by a beep every 30 seconds. What can you do to avoid this? You should, of course, replace the batteries regularly before they are getting close to their expiry time and you should have spare batteries at home. However, when it comes to sealed longlife battery units, which last ten years. This situation is much harder to prepare for, as you cannot realistically have a set of complete smoke alarms in your drawer, just in case.
Kidde Fire Safety Products have come up with a brilliant concept to resolve this age old problem. Their longlife, sealed optical smoke alarm 10y29, which has a ten year lifespan, will detect the gradual weakening of its battery and then ensure that the alarm only starts beeping during daytime. This is achieved by monitoring the strengthening/weakening pattern of the battery voltage over a period of time as temperatures rise and fall during the day and nigh time. From this patterns the onboard chip of the smoke alarm will then define the day period and will only then raise the low battery alert during this time. An ingenious solution to a long standing problem.

Fig 1. Normal operation (showing the increasing and decreasing voltage pattern during daytime and night time)

kidde-10y29-info-1

Fig 2. Dropping voltage and the response of traditional smoke alarms which start beeping in the night

kidde-10y29-info-2

Fig 3. Kidde’s 10y29 smoke alarm, which records the night time lows but only starts beeping in the daytime

kidde-10y29-info-3

Replacement of old Kidde smoke alarms

As well as testing your smoke and heat alarms on a regular basis, it is important to make a note of when the units actually need to be replaced. Studies have shown that the functionality of smoke and heat alarms can start to deteriorate when they reach a lifespan of 10 years. Each smoke and heat alarm should have a “replace by date” visible on the outside of the unit and we recommend that you adhere to this guideline.

When replacing a smoke alarm it can be quite difficult to recognise a suitable replacement product. In some cases, you may find that the current alarm model has been discontinued. With battery operated alarms, as there is no wiring in place, it is much easier to replace the unit for another smoke alarm with like-for-like features. Mains powered alarms are hard wired and are most likely interconnected during installation. It is because of this that finding replacement detectors can be difficult.

Working with Kidde Safety Europe, Safelincs are able to provide a list of mains powered discontinued Kidde smoke and heat alarms, along with their suitable product equivalents.

Discontinued Alarm Replacement Alarm
123/9HI KEKF10
123i KEKF10
123/9HILL KEKF10R
223/9HI KEKF20
223/9HILL KEKF20R
1275H KEKF10
323/9HI KEKF30
323/9HILL KEKF30R

The new alarms will interlink with other, still working units of the previously installed smoke alarms. This means that there is no need to replace all of the units within a system if only some of the installed detectors have reached the end of their recommended lifespan. All new mains powered smoke and heat alarms are provided with a mounting bracket and a wiring connector. It is important to note that you need to replace the existing mounting base and re-connect the wiring to fit the new units. With any mains powered alarms, all electrical work should be carried out by a qualified electrician.

Safelincs offer a smoke alarm reminder service which allows customers to be notified when their smoke and heat alarms are due to be replaced, when the batteries need to be changed and reminds customers to test their alarms on a regular basis. The service is completely free and customers can choose if they wish to be reminded by email, SMS text message or by Twitter.

CO Alarm for Caravans and Motorhomes

Prepare for the summer season by installing a CO alarm for caravans. Because caravans are a confined space, the potential for the build-up of deadly carbon monoxide gas is greater. If you have already fitted a CO detector, ensure that you carry out your pre-holiday safety checks. This should include checking or replacing the batteries and testing smoke, heat and CO alarms. It is also advisable to check when your alarms need replacing. Sensors in these types of alarms become less effective over time and will need to be replaced after 10 years.

Kidde 7DCO for caravans and motorhomes
The Kidde 7DCO CO Alarm for caravans and motorhomes

Choosing a CO alarm for caravans and motorhomes

Not all carbon monoxide alarms are suitable for use in caravans or motorhomes. Choosing a suitable alarm is important because if the CO alarm you have isn’t recommended for use in camping environments, you may not be alerted to dangerous levels of CO gas. Choose an alarm that is:

  • Kitemarked to British Standard BS EN50291-2
  • Certified for use in caravans
  • Suitable for wall mounting
  • Battery operated
  • CE marked

Kidde 7DCO

The Kidde 7DCO is ideal for caravans. It can be easily wall mounted using the fixings included in the pack. The digital display shows readings taken every 15 seconds and will indicate any changes to the level of CO gas detected. The alarm is supplied with 3 x AA batteries that are easy to replace when the warning chirp indicates that the power is low.

The Kidde 7DCO is certified for use in caravans and has a warranty for the full 10 year lifespan of the product.

Caravan fire extinguisher and CO alarm
Kidde 7DCO can be easily wall mounted in your caravan or motorhome
Kidde Carbon Monoxide Alarm - 7DCO / 7DCOC
Kidde Carbon Monoxide Alarm - 7DCO / 7DCOC
  • Product Life: 10 years
  • Battery: replaceable AA alkaline batteries included
  • Warranty: 10 year warranty
  • Displays CO levels from 10ppm
  • Peak Level Memory - recalls highest CO levels
  • Ideal for domestic use and camping, caravans & boats
  • Kitemarked to BS EN50291-1 and BS EN50291-2
  • Also suitable for the 2022 Welsh legislation
£15.21 ex VAT
£18.25 inc VAT
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