20.1 Commentary

Location and Visibility:

MCPs must be strategically located and easily distinguishable.
They should be positioned so occupants cannot exit a storey or building without passing one.
Install sufficient MCPs to minimize alarm activation delay, especially in high-fire-hazard areas.

Unsuitable Areas:

MCPs may be omitted in unsupervised public areas prone to misuse (e.g., public car parks), where emergency voice communication systems might be used instead.

Placement Requirements:

MCPs are required near all storey exits and exits leading to open air with access to safety.
MCPs are not required near doors leading to enclosed courtyards or flat-roofed areas without a clear path to safety.

Building Openings:

Consider MCP placement at building openings like roller shutter doors if they serve as viable escape routes. If not, MCPs may be unnecessary at those points.

20.2 Recommendations

The following recommendations are applicable.

1. Operation and Type:

MCPs should be Type A (BS EN 54-11), which automatically activates the alarm when the frangible element is broken or displaced.
All MCPs should be identical and equipped with a protective cover.

NOTE 1 The Type A manual call point is defined in BS EN 54-11 as follows. “Type A Direct operation. A manual call point in which the change to the alarm condition is automatic (i.e. without the need for further manual action) when the frangible element is broken or displaced.”

NOTE 2 The fitting of a protective cover to the type A manual call point is not deemed to conflict with 20.2a).

2. Response Time:

The delay from MCP activation to the “Evacuate” signal should be no more than 3 seconds. Up to 10 seconds may be acceptable with authorization.

3. Location and Distribution:

MCPs must be on escape routes, near all storey exits, and exits to safety. In multi-storey buildings with phased evacuation, MCPs should not be on stairway landings to prevent inappropriate evacuations.
Ensure no one travels more than 45 meters to reach the nearest MCP. For final layout adjustments, ensure no more than 30 meters initially, with a maximum of 45 meters after fit-out.
Reduce distances to 25 meters and 16 meters for areas with occupants with limited mobility or high fire hazard.

4. Special Hazards:

Install MCPs near high fire hazard areas (e.g., kitchens, paint spraying) with considerations for frangible elements and equipment certification.

5. Mounting and Visibility:

MCPs should be mounted 1.4 meters above floor level, well-lit, and visible. Lower mounting is acceptable for wheelchair accessibility.
They can be flush-mounted but must protrude at least 15 mm if viewed from the side.

NOTE 4 These distances are arbitrary, but reflect the maximum acceptable distances between any point and the nearest storey exit commonly applied to many premises.

6. Public Car Parks:

If using an emergency voice communication system instead of MCPs, it must be approved by the relevant authority and meet BS 5839-9 standards, with Type B outstations and a master station in a manned location.

NOTE 5 In both examples given in g) other considerations also apply. Kitchens or food preparation areas might require the use of a non-glass frangible element to avoid the possibility of food contamination with glass fragments. The spraying area might require the use of equipment certified for use in potentially explosive atmospheres (see Clause 10).

NOTE 6 The measurement ought to be made between the finished floor level and the centre point of the frangible element.

NOTE 7 The figure of 1.4 m is arbitrary, but reflects long established custom and practice. A minor difference (e.g. less than 300 mm) in mounting height (e.g. to align with the mounting height of light switches) need not be regarded as significant, nor need it be recorded as a variation.

NOTE 8 Guidance in support of national building regulations (e.g. in England and Wales, Approved Document M [6] under the Building Regulations 2010 [2]) recommends that switches and controls be mounted no higher than 1.2 m above floor level, so that they are accessible for disabled people.

Figure 6 — Manual call points on escape routes [see 20.2d)]

20 Manual call points