15.1 Commentary

For maximum benefit, a fire alarm and detection system must promptly summon the fire and rescue service. The following recommendations are applicable.

Primary Means of Summoning:

In occupied buildings, occupants should call 999 (or 112) even if automatic alarm transmission to an ARC is available, as automatic systems can fail.
Fire alarm sounders should not interfere with emergency calls.

Manual Fire Alarm Systems:

Automatic transmission to an ARC is generally unnecessary if the building is occupied, as occupants can call the fire and rescue service.
Automatic transmission might be beneficial for large, complex buildings or those with low occupancy.

Category L Systems:

Manual summoning of the fire and rescue service by occupants is usually sufficient.
In critical facilities (e.g., hospitals), a secondary automatic transmission may be necessary for life safety.

Category P Systems:

Automatic transmission to an ARC is important for property protection when premises are unoccupied.
Category P2 systems need automatic transmission if the detection coverage is significant.

Multiple Occupation Buildings:

Responsibility for summoning the fire and rescue service must be clear.
Automatic transmission to an ARC might be needed for reliability.

Reliability Considerations:

Manual and automatic means of summoning the fire and rescue service must be reliable.
BS EN 50136-1 defines categories of alarm transmission systems (ATS), with SP1-SP6 for single paths and DP1-DP4 for dual paths.
Alarm transmission systems with ATP failure reporting are preferred.

Commercially Operated ARCs:

Ensure ARCs have formal arrangements with local fire and rescue authorities for rapid communication.
Fault signals can be transmitted separately to ensure they are addressed when premises are unoccupied.

Intruder Alarm Systems:

Fire alarm signals can be routed through intruder alarm system equipment, provided it meets BS 5839 standards for power supplies, battery capacity, and cable requirements.

15.2 Recommendations

The following recommendations are applicable.

a) Ensure arrangements for summoning fire and rescue services minimize risk to the responsible person. Do not use systems that transmit pre-recorded messages directly to fire services via public emergency call systems.

b) In occupied buildings, occupants should call fire services using the public emergency call system.

c) Fire alarm signals should not be so loud as to interfere with telephone calls in designated calling areas.

NOTE 1 Cases have been reported in which the frequency of the alarm sounders has been such as to corrupt tone dialing systems, leading to failure of the emergency call.

d) The designer should ascertain if automatic transmission of alarm signals to an ARC is required.

e) If early summoning of fire services is critical for occupant safety, automatic transmission to an ARC should be provided unless reliable manual summoning arrangements exist.

NOTE 2 In the case of shopping centres and hospitals, conformity to the Technical Handbooks (see www.scotland.gov.uk/Topics/Built-Environment/Building/Building-standards/publications/pubtech)4) that support the Building (Scotland) Regulations 2004 [3] necessitate automatic transmission of fire alarm signals to an ARC.

f) In residential care premises, facilities should be provided for automatic transmission of alarm signals to an ARC.

NOTE 3 In the case of residential care premises, conformity to the Technical Handbooks (see www.scotland. gov.uk/Topics/Built-Environment/Building/Building-standards/publications/pubtech)5) that support the Building (Scotland) Regulations 2004 [3] necessitates automatic transmission of fire alarm signals to an ARC.

g) Except in the case of continuously occupied premises, Category P systems should incorporate a means for automatic transmission of fire signals to an ARC.

15 Communication with the fire and rescue service