In reply to Bjartur i Sumarhus:
> Do you know if the fire service sign off a building using building regs as the rule? Or do they have their own criteria?
In Scotland they don't (England, I'm not sure about but I imagine it's the same) but they are consultees in the process and will ultimately confirm they have no further objections to what is being proposed in the design. I'd have assumed that the reg.s will have been drafted following very detailed consultation with high level fire services officers. The full building 'sign-off' you describe is done by the main contractor, in that they confirm in writing that the construction works have been done in accordance with the approved documents. These documents are all those items, drawings, specifications, specialist reports etc which were submitted as part of the Building Warrant application. Again I'm talking about in Scotland, which I know is different in that we don't have independent inspectors. The Building Control officer will inspect the works at certain key points as they see fit. On most projects (above a certain size), details or elements of the design change from what was originally submitted for approval, and these are picked up, usually in chunks, in 'Amendments to Warrant'.
To get back to your question, the Fire Services will inspect the drawings being submitted and have meetings with the designers - including, sometimes, specialist Fire Engineering consultants - to make sure it's understood what they require in terms of physical provision eg. hydrants in the street, dry riser inlets, where they connect the fire engine to the system of pipes inside the building to which they connect their fire hoses. Dry riser outlet positions are stipulated in the Building Regs. as are smoke venting and smoke lobbies. Fire Services Officers will also make sure the compartmentation is correct in terms of duration: low, med or high which in real terms translates to 30minutes, 60mins or 120mins fire resistant construction. Materials are tested independently so they can gain the necessary BBA certificates showing they will achieve those levels of fire resistance with any given construction. For example, one layer of 15mm fireline board on either side of a 70mm metal C-stud, with 50mm Isover insulation gives you 60mins FR.
FYI, on any larger scale building I've helped design, at the meetings I've had with the Fire Services, staff have always said fires are fought from the floor below the level of the fire. They also visit the building in question for a walk through and familiarise themselves with the layout so they can have an idea of how they would tackle a fire in various locations.
Travel distance from the furthest-most points in the building to escape stairs are likewise stipulated to make sure escapees can reach a place of safety in what is considered an acceptable time scale. In some cases, a single direction of travel is permitted before you reach a stair or diverge and choose which stair to escape via. Everything should of course be clearly signed and there should be emergency lighting which remains visible in the event of power failure.
Minimum clear escape widths are also stipulated in the reg.s; you are not allowed to store or keep items (sofas, tv,s, general rubbbish etc) anywhere along these escape routes. I've seen some photos of this tragic case which show all of the above, a situation which shouldn't have been permitted. It's for others to say why these items were dumped where they were and then, presumably left to remain as a fire hazard and an obstruction.
Edit: typos
Post edited at 11:18