Dave Naughton

Fire door inspector here. Mike has covered the regulations well, so I'll just add what I see on site. Fire resistance and PAS 24 are two separate tests, and each one covers the exact doorset that was tested: leaf, frame, hinges, lock, letter plate, spyhole, seals and gaps. The trap is the hardware. A different lock, an extra deadlock or a letter plate that wasn't in the fire test puts the door outside its fire evidence, even if the security side is fine. So ask the supplier for both sets of test evidence and check the hardware listed in each matches what is actually being supplied. A new leaf in the old frame is only covered if the leaf maker's evidence allows fitting into an existing frame of that type. If it doesn't, you need the complete doorset. When it arrives, check the label or plug on the door edge matches the paperwork, the intumescent and smoke seals are fitted (that's the S in FD30S), and the gaps are within the evidence, usually around 3mm. The rating itself comes from the building's fire strategy. Whether the existing door gets replaced at all is for the fire risk assessor to weigh up before anything is bought.