Upgrading nominal fire doors in Grade II Listed office building

[jackwratten]

I'm redecorating a Grade II Listed office building and have upgraded several doors with Envirograf intumescent coatings and seals, adding intumescent felt behind all ironmongery and ensuring the door closers work correctly. Being old, the hinges are heavily over-painted and probably non BS stamped (but you cannot see for sure). The hinges are all intact, firmly screwed in and have held the doors for decades.

The FRA says they all need to be BS 1154 (I think he meant BS 1935) which would mean replacing over 100 hinges. I'm not replacing any of these doors with new ones, as they having some heritage value, so is it necessary to replace these working hinges?

They need to be FD30 doors and the building is low occupancy shared office use over 2 stories with all the right fire alarms, extinguishers, signage and exits. Any guidance would be much appreciated.

[AnthonyB]

What's the detection coverage?

It's probably tolerable under the circumstances, although even if they perform long enough for life safety, premature failure will impact property protection. The problem is without testing is difficult to say they will work long enough.

[jackwratten]

The alarm covers "Escape Route and Rooms Forming Part of the Escape Route" and is L4 type throughout the building.

Given this is a Grade II listed building and over 200 years old, I'm not ripping out original doors and feature (like brass Victorian locks etc) so we would like to keep the hinges in place as they all work and have held the doors for decades.

Any additional thoughts would be welcome and greatly appreciated.

[AnthonyB]

Better AFD would be preferable so there is less reliance on the door performance for any length of time, but it could be deemed tolerable in an FRA