Fire Safety

The Different Types Of Fire Alarms And Where Professionals Install Them

Selecting and installing smoke alarms correctly - and making sure they are in working order - is a crucial role for housing providers and M&E contractors, together providing the best protective standard possible for tenants.

It comes down to fitting a suitable alarm in an appropriate location, and ensuring compliance with legislation and recommended best practice.

For instance, under the Smoke and Carbon Monoxide Alarm (England) Regulations 2015, private landlords are required to have at least one smoke alarm installed on each storey of their properties, and a CO alarm in any room containing a solid fuel burning appliance (e.g. a coal fire, wood burning stove).

BS 5839:6 is also a key standard for fitting alarms in domestic premises, as it outlines the best practice for compliance with fire safety legislation. This should therefore be considered an authority for private and social housing providers.

BS 5839:6 was revised in early 2019, for a simplified guide advising the latest revisions, download our guide below:

To consider:

Before purchasing a certain type of alarm – whether this be carbon monoxide, heat or a smoke alarm – always ensure it complies with British Standards. For self-contained smoke alarms this is BS 5446 Part 1 (2000) and for an alarm system this is BS 5839 Part 1 (2013).

Also ensure the alarm carries a British or European approval mark, such as a Kitemark. Also, consider its implementation; alarms can be powered by battery or mains, or a combination of both (typically with a battery as a backup for mains power). They can also be interlinked via wireless radio frequency (RF) technology, or be hard wired interlinked.

Different types of fire alarms

Categorically, there are four main types of alarm on the market, each with separate installation requirements:

(1)    Ionisation alarms – these are sensitive to small particles of smoke produced by fast flaming fires.

Installation:  Ionisation alarms should not be placed near kitchens/hallways as they are more liable to false alarm due to cooking fumes. It is also important to note that in support of UK Fire and Rescue Services, who no longer recommend using ionisation alarms, FireAngel has also moved away from ionisation technology and phased this out in April 2018. See why here.

(2)    Optical alarms – these are effective at detecting larger particles of smoke from slow-burning, ‘smouldering’ fires.

Installation: These can be placed near kitchens and in circulation spaces, but not too close to poorly ventilated bathrooms as they are liable to false alarm when exposed to steam.

(3)    Multi-sensor alarms – Thermoptek multi-sensor alarms contain two separate sensing elements – optical and heat detection. As the unit monitors for two different by-products of fires (smoke and temperature), its response to all types of fire is vastly improved over traditional single sensor alarms. They are also less prone to false alarms associated with the ionisation and the optical type alarms and hence why UK Fire and Rescue services recommend Multi-Sensor technology.

Installation: Multi-sensor technology eliminates the need to fit separate ionisation and optical alarms, and provides a faster reaction to both fast-flaming and slow smouldering fires in a single alarm. As a result, BS 5839-6 recommends the use of multi-sensor technology in all rooms except the kitchen.  Find out more here. 

(4)    Heat alarms – these can detect an increase in temperature and are insensitive to smoke. Heat alarms are best suited for kitchens, garages and lofts.

Installation: BS 5839: Pt.6: 2019 recommends that heat alarms should be used in kitchens, but should also be part of an interconnected fire alarm system.

Best practice for positioning CO and fire alarms

Smoke and heat

The British Standard BS 5839-6:2019 recommends that smoke and heat alarms be installed:

  • On the ceiling, as central as possible in the room
  • Sited 300mm from walls and light fittings – this ensures the alarm is out of any ‘dead air’ spaces where the airflow may be blocked
  • Placed within 3m of every escape door and bedroom door to ensure audibility
  • Positioned between high risk rooms and bedrooms
  • For peaked and sloped ceilings – make sure there is a maximum of 600mm vertically down from the apex for smoke alarms, and 150mm vertically down for heat alarms

Heat alarm

Recommended: kitchen, garage, loft

Smoke alarm

Recommended: All circulation areas (e.g. landings), bedrooms and sitting rooms. 

Carbon monoxide

The British Standard EN 50292 standard recommends that a CO alarm should be installed:

  • Between 1m–3m from all potential sources of carbon monoxide (fuel burning appliances)
  • Sited 300mm from walls and light fittings – this is to ensure that they are outside of
    any ‘dead air’ spaces that occur in corners and spaces where the airflow may be
    blocked
  • If the fuel burning appliance is in a confined space (e.g. a boiler room) then the
    alarm should be sited on the ceiling just outside the room
  • If there is no fuel-burning appliance, then place the alarm at breathing height e.g. bed’s head height in bedroom

Carbon Monoxide Alarm

Recommended: In all rooms with fuel burning appliance, bedrooms. 

The standard also recommends that CO alarms should not be installed:

  • In an enclosed space
  • Where it can be obstructed
  • Directly above a sink
  • Next to a door, window, extractor fan, air vent or similar ventilation opening
  • Where the temperature may drop below –5 ºC or exceed 40 ºC.

Want to install a mains-powered  smoke alarm system in a property? We’d recommend downloading our free guide to specifying and installing here:

Maintaining alarms after installation

Whilst mechanical and electrical contractors need to ensure alarms are functioning and placed in the most suitable location, alarms also need to be routinely tested and cleaned. As described in BS 5839: Pt 6, this testing/maintenance of the property depends on the system grade e.g. an interlinked grade A system with a control panel should test at least one detector a week. It is also recommended to delicately clean your fire alarms with a vacuum cleaner fitted with the soft brush once a month.

For an overview of quick user guides (including what to do when there is low battery beeping or chirping) – see our kitchen safety guidelines for tenants

Given the majority of housing associations (HA) give new tenants a ‘home-owners pack’ with instructions of how to test fire alarms inside, there is a responsibility on the tenant to do this. Especially, as HA only usually coincide testing of smoke alarms with an annual gas maintenance or electrical check.

As a result of this, it is recommended to install a fire safety system that is high quality, but also easy to use. For instance, by installing FireAngel Specification range of alarms in the home, landlords can be confident that alarms are continually working after fitting as they are mains powered with a tamper proof sealed for life battery backup.

Furthermore, by including an alarm control unit, there is no necessity for physically testing the alarms – all the testing can be done remotely from one centralised location. This is particularly beneficial for social housing, which has a large proportion of vulnerable tenants who may find it difficult (or be unable) to reach the alarms, which are typically located on the ceiling.

For more information on fire safety legislation and guidance in social housing, download our free eBook below