Passive fire protection is the part of a building that contains a fire without anyone doing anything: compartment walls and floors, fire doors, cavity barriers, penetration seals and structural protection. In London the difficulty is rarely choosing a product. It is proving what is already there, in buildings that were converted, subdivided and re-serviced by people who left no record.
What counts as passive, and where it lives
Compartment walls and floors, protected escape routes, fire doors and their seals, cavity barriers behind cladding and in roof voids, penetration seals where services cross a fire separating element, and fire resisting protection to structure. Almost all of it is buried behind finishes or above ceilings, which is why it is the part of a building most often assumed to exist rather than seen.
Why the London stock makes it hard
Period terraces converted to flats, warehouses converted to offices and flats, and decades of re-servicing through the same risers. Each alteration crossed a fire separating element and each one either reinstated the seal properly or did not. The drawings, where they exist, describe an earlier building. What a survey can say about compartmentation is therefore limited by what it was allowed to open up.
What a survey has to record
Where each element is, what it was found to be, the evidence for that finding, and explicitly what could not be accessed. A report that states a compartment line without saying how it was verified is an opinion. The no-access list is the most useful part of the document, because it is the list of things the next person still has to find out.
Remedial work, and the record it leaves
Firestopping is buried by the next trade, so the photograph, the location, the tested system used and the installer are the only evidence that will ever exist. Third party certificated installers produce that as a matter of course. Work with no record is work that will be surveyed again in five years by somebody who cannot tell whether it was done.
Questions people ask about passive fire protection London
Is passive fire protection part of the fire risk assessment?
Yes, and it is usually the part the assessment has to qualify. Where compartmentation could not be verified, the assessment records that as a limitation rather than assuming the separation holds.
Who is competent to do the work in London?
Installers with third party certification for the systems they are fitting. The certification matters less as a badge than as the reason a record of what was installed exists at all.
How often should passive protection be surveyed?
On a cycle set by the risk assessment, and again after any work that crossed a fire separating element. A new cable through a sealed opening is a new breach whatever the last survey said.
What counts as fire protection equipment, as against passive protection?
Fire protection equipment is the part that does something when a fire starts: detection and alarm, emergency lighting, extinguishers and blankets, sprinklers and other suppression, smoke control fans and dampers, hold open devices that drop a door. Passive protection is the part that does its job by simply being correct: compartment walls and floors, protected escape routes, fire doors and their seals, cavity barriers, and the seals around every service that passes through a compartment. The distinction matters because equipment is serviced on a schedule by somebody who leaves a certificate, and passive protection is buried by the next trade and is only ever as good as the record of what was installed and where.
What is the purpose of passive fire precautions?
To buy time by keeping the fire where it started and the escape route usable while people leave. Everything else follows from that: a compartment wall holds for a stated period so the fire does not reach the stair, a fire door closes so smoke does not enter the lobby, a cavity barrier stops fire running behind a facade, and a penetration seal restores the wall that a pipe was put through. None of it needs power, a person or a service visit to work, and none of it announces that it has failed, which is why a survey that records what was found, what the evidence for it was and what could not be accessed is the whole of the assurance.