What types of properties does BS5839:6 cover?
| Applicable Properties | Non-Applicable Properties |
| Bungalows | Hostels |
| Multi Storey Houses | Caravans |
| Individual Flats & Maisonettes | Boats (other than permanently
moored houseboats) |
| Mobile Homes | Communal parts of purpose built
sheltered housing, blocks of flats or maisonettes. |
| Sheltered Housing | Any premises used for purposes
other than a dwelling (small shops, small factories etc) |
| Houses providing NHS supported living | |
| Mansions | |
| Houses divided into several single-family dwelling units. |
BS5839:6 Fire Detection Grading System – Type, Control & Indicating Systems
The Fire Detection Grades are effectively different combinations of Fire Detection and Control / Indicating Equipment. The system specified for your domestic property will fall into one of or several of the categories below depending on requirements.
Grade A
A Fire Detection and Alarm system (FD&A) which incorporates Control and Indicating Equipment (CIE) conforming to BSEN54 2 and PSU equipment conforming to BSEN54 4. The system is designed and installed in accordance with all the recommendations of sections 1 to 4 inclusive of BS5839:1
Grade B
A FD&A. system comprising fire detectors (other than smoke and heat alarms), fire alarm sounders and CIE that either conforms to the requirements of Grade A above or to “Annex C” of this part of BS5839.
Grade C
A system of Fire Detectors and Alarm Sounders (which may be combined in the form of smoke alarms) connected to a common power supply, comprising the normal mains and a stand by supply, with central control equipment.
Grade D1
A system of one or more mains powered smoke alarms each with a tamper proof stand by supply consisting of a battery or batteries.
Grade D2
A system of one or more mains powered smoke alarms each with an integral stand by supply consisting of a user replaceable battery or batteries.
Grade E
A system of one or more mains powered Smoke Alarms with no stand by supply. (The system may, in addition, incorporate one or more Heat alarms, with or without stand by supplies).
Grade F
A system of one or more battery powered Smoke alarms, each with an integral stand by supply (the system may in addition, incorporate one or more battery powered Heat alarms).
Interlink Requirements for Grades D,E & F
Where more than 1 Smoke alarm is installed, the smoke alarms normally need to be interlinked (13.2). Any Heat alarms will also need to be interlinked with the Smoke alarms.
Most residential applications in the UK will fall into Grades D or F with a few exceptions
While it is possible, and acceptable under the Code, to have a mixed-Grade system installed, this is something that should be done based on clear requirements being identified during a risk assessment and in coordination with appropriate Building Regulations and enforcing authorities. An example would be a Grade A Category LD2 system in the communal areas of a HMO supplemented by separate Grade D1 Category LD1 systems in each residential unit.
BS5839:6 System Categories – What areas should be protected?
The system categories are essentially different levels of coverage required depending on the fire risk in those areas of the property. They describe the level of protection that the system provides.
It gives guidance on where and how many alarms installed will affect how quickly a fire is detected generally the higher the category of system, the higher the level of protection.
The standard states that the level of protection to the occupants needs to be directly proportional to the fire risk.
The fire risk in each area of the property is calculated based on the number of previous incidents recorded. For example 54% of fires previously reported to the fire service have started in the kitchen – Making this a high risk area vs the bathroom at 2% of fires.
Life Protection Systems In order of protection
LD3 – Minimum Protection
Detectors in all circulation spaces that form part of the escape routes from the dwelling.
Escape Routes such as:
- Hallways
- Landings
LD2 – Medium Protection
Detectors in all circulation spaces that form part of the escape routes from the dwelling and in all rooms or areas that present a high fire risk to occupants.
Escape Routes and High-Risk Areas such as:
- Hallways
- Landings
- Livingroom
- Kitchen
LD1 – Maximum Protection
Detectors in all areas where a fire could start such as:
- Hallways
- Landings
- Living Room
- Kitchen
- Bedrooms
- Airing Cupboards
- Meter Cupboards
Use Specific Guidance
The legally required category differs depending on the age and use of the dwelling. This is because building standards have changed over time and regulations have become more comprehensive.
Rented Dwelling
D1 / LD2D – New Build / Existing
Grade D1
A system of one or more mains powered detectors, each with a tamper-proof standby supply consisting of a battery or batteries.
Note D:
Heat detectors should be installed in every kitchen. A smoke detector should be installed in the principal habitable room. Where more than one room might be used as the principal habitable room, a smoke detector should be installed in each of these rooms.
Owner Occupied Dwelling
D2 / LD2D – New Build (2-3 Storey)
A system of one or more mains powered detectors, each with an integral standby supply consisting of a user replaceable battery or batteries.
Note D:
Heat detectors should be installed in every kitchen. A smoke detector should be installed in the principal habitable room. Where more than one room might be used as the principal habitable room, a smoke detector should be installed in each of these rooms.
Sheltered Housing – Existing
- Individual Dwellings Grade D2, Category LD2Q
- Communal Area Grade A, Category L4/L5
Note Q:
Where sheltered housing is upgraded, electrical work such as a re wire is undertaken, or smoke alarms are replaced; a Grade D (D1 or D2) category system should be installed.
Sheltered Housing – New / Materially Altered
- Individual Dwellings – Grade D2 Category LD1J
- Communal Area – Grade A Category L4/L5
Note J:
Detectors may normally be omitted from roof voids unless there are specific significant fire hazards such as gas boilers or electrical equipment for photovoltaic systems.
Self-catering premises or premises with short-term paying guest
- Grade D1, LD1J
Note J:
Detectors may normally be omitted from roof voids unless there are specific significant fire hazards such as gas boilers or electrical equipment for photovoltaic systems.
House of Multiple Occupancy (HMO) – Existing (1-2 Storey)
- Grade D1, LD2D
Note D:
Heat detectors should be installed in every kitchen. A smoke detector should be installed in the principal habitable room (see 3.28). Where more than one room might be used as the principal habitable room, a smoke detector should be installed in each of these rooms.
Other Dwellings
- A system conforming to BS5839:1 for a category P1 system (Not part of BS5839:6)
Examples of fire detection systems in different property types
Always conduct a fire risk assessment to determine risks specific to your property. The following is general advice:
HMO up to two storeys with no floor greater than 200m2:
Grade D1 Category LD1 throughout.
Other HMOs where each dwelling comprises a single room:
Mixed system: Grade A Category LD2 in common areas, in accordance with BS 5839-1: 2017 Category L2, and with connected heat detectors in bedsits which have cooking facilities. Additionally, Grade D1 Category LD1 in the bedsit itself (not connected to the communal system) to protect the sleeping occupant(s).
Other HMOs where each dwelling comprises a two or more rooms:
Mixed system: Grade A Category LD2 in common areas, in accordance with BS 5839-1: 2017 Category L2. Additionally, Grade D1 Category LD2 in the dwelling itself (not connected to the communal system) to protect the sleeping occupant(s).
Two storey house converted to self-contained flats (prior to 1991 Building Regulations):
Mixed system: Grade D1 Category LD2 in common areas and heat detector in each flat (room / lobby opening onto escape route) connected to the communal system, plus Grade D1 Category LD3 in each flat (not connected to the communal system) to protect the sleeping occupant.
Three to six storey house converted to self-contained flats (prior to 1991 Building Regulations):
Mixed system: Grade A Category LD2 in the common areas, in accordance with BS 5839-1: 2017 Category L2 and with a connected heat detector in each flat (connected to the communal system), plus Grade D1 Category LD3 in each flat (not connected to the communal system) to protect the sleeping occupant.
Single household with fewer than four storeys:
Grade D1 Category LD2 and cellar.
Single household with four or more storeys:
Grade A Category LD1 and cellar.
Flat in multiple occupation (FMO) single storey:
Grade D1 Category LD2 and additional heat detector in the kitchen (and shared living room depending on risk).
Need some advice or help?
Please call Midland Fire Security Services 01283 741000 or email info@midlandfire.com
