Fire alarm variation continued

(14) To continue with our last blog regarding fire alarm variations when designing fire alarms to BS5839.

Thus, for example, although this BS5839. standard recommends that no one should travel further than 45 m to reach
the nearest fire system manual call point, a competent person might judge that, in a particular building, a distance of 47 m is acceptable because, perhaps, this leads to the most appropriate locations for the manual call points. Similarly, in an office building, it might be judged that, say, sound pressure levels of 57 dB(A) could be acceptable in a number of outer small offices, since to achieve the 60 dB(A) as recommended in this standard, the cost to achieve the additional three decibels would not justify the cost.

Recommendations:

1) Any variations from the recommendations of the fire alarm design code part of BS 5839 incorporated within a specification
or design proposal should be clearly identified, so that they are obvious to any party from whom approval of the specification or design proposal may be sought, such as the user, purchaser, enforcing authority or insurer.
2) Any variations from the recommendations of the fire alarm design code part of BS 5839identified or proposed during
installation or commissioning, but not clearly identified in the documented design, should be documented
(other than in the case of errors or “snags” for which rectification is proposed), for subsequent approval.