Acceptance Testing of a New Addressable Alarm System
A new addressable fire detection system is being commissioned in a 5-storey office. The installer provides a commissioning certificate stating that all 620 devices were tested and passed. The assessor reviews the cause-and-effect matrix and notices that the matrix has no entry for the basement plant room, which contains two detectors and a sounder circuit. The installer says the plant room is "not a occupied area" and was omitted to save time, and that the panel's default programming will cover it. During a walk test of one floor, the assessor observes that a detector in a riser cupboard triggers an alarm but the door-closing signal to the adjacent corridor door does not operate. The building is due to be occupied in ten days.
1. Evaluate the commissioning certificate and the cause-and-effect matrix, and identify what must be verified before occupation.
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The certificate asserts that all 620 devices were tested, but the matrix omission for the basement plant room shows the system was not verified against its design intent, so the certificate's scope is unreliable. A plant room is a fire risk area even if not normally occupied, and detectors there must be linked to an appropriate response; relying on default programming is unacceptable because defaults are not a design and their behaviour is unverified. The door-closing failure on the riser cupboard detector is a second, independent defect: either the matrix omits the door-hold-open release for that zone, or the interface is faulty, and either way the smoke control and compartmentation assumptions are not met. Before occupation the assessor should require: a completed cause-and-effect test for every zone including the plant room, witnessed by a competent person; correction and retest of the door release interface; a full device-by-device verification or a documented sampling regime agreed with the authority; and a revised certificate reflecting the actual tested scope. Ten days is sufficient only if these are treated as priority items.
2. The installer offers to sign a revised certificate confirming the plant room is covered "by default programming." How should the assessor respond?
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The assessor should decline to accept a certificate worded that way. A certificate should attest to tested performance against a defined design, and "covered by default programming" is not a test result; it is an assumption. Accepting it would transfer an unverified risk into the occupied building and would mislead the authority and the responsible person. The correct response is to require the plant room to be added to the cause-and-effect matrix with a defined alarm response, then tested and witnessed, and the certificate to record that test. If the installer refuses, the assessor should record the refusal, report the system as not verified for that zone, and advise the responsible person that occupation should not proceed on the basis of the current certificate. The assessor's independence is the point of the role; a certificate that records an untested assumption is worse than no certificate because it creates false assurance.