When it comes to fire alarm design it is amazing how many trades, professions and professionals just don’t get it. Firstly there is the misconception that the designer will choose the category of the system – Wrong! It’s not their job. The choice of system category is ultimately that of ‘the responsible person’. They may have help and guidance from other stakeholders e.g. fire risk assessor or insurer. Occasionally they will be given a category by an enforcing authority such as the Fire Brigade or Building Control. Once the category has been chosen it is the job of the designer to ensure the specification meets the category entirely.
Being the official designer brings a lot of legal responsibility. A person remains ‘the designer’ in perpetuity (unless wholesale changes or re-design takes place) even if a different maintaining company takes over the system in the future. Therefore a designer will not cut corners. In a commercial, competitive environment ultimately they will provide a design to your specification but the category on the certificate will reflect that. Indeed if the design meets no specific category this too will be noted on the design certificate.
Many building contractors give designers a schematic with devices already in position. However they often don’t quite realise this means legally they are now the official designer. A fire-alarm designer will be completely unwilling to certificate somebody else’s poor design, and why should they? Many architects, consultants, builders and electrical contractors completely misunderstand and underestimate the design process. It involves understanding detectors, coverage patterns and spacing. They need to know how different structures, particularly ceilings, affect detector coverage and spacing. They have to understand how to incorporate loop calculations, battery calculations control-panel design software etc. etc.
Often it is at the end of a contract when the trouble starts. This when the Fire Authority, or more likely building control, will require all the correct certification before they sign the building off. Often because nobody understood or perhaps were unwilling to pay for the design element problems now ensue. A finished building, a Building Control official who won’t sign it off and a designer who won’t certificate someone else’s poor design.
The design process can take days and cost hundreds of pounds and all too often this is not factored in. However skimping on design can be very costly in the long run.