Solicitors offices tend to be fairly low risk premises from the point of view of the activities that go on there and the number of persons present, and the processes that are carried out.
On the other hand my experience is that solicitors offices are amongst the worst for general compliance matters- electrical and pat testing, old wiring with huge use of adaptors and extension leads and some I have worked for have had pretty poor standards of practice and awareness- cooking, portable heaters, door wedges, training, building maintenence (eg basement ceilings) housekeeping in the basement etc. You may wisk to consider the loss of files and business continuity.
Apart from the above, for life safety an occupied office is generally at the lower end of the scale of risk and I personally would feel easy about relaxing standards where a fire will be detected and evacuation complete in the early stages of a fire.
Where there is a risk that a fire is likely, or may not be detected in its early stages or may develop and grow rapidly or could affect the means of escape in a critical area (besement ceiling beneath foot of stairs? ) I would apply the guidance standards, but otherwise I would feel easy about traditional doors of reasonable construction even without upgrade and provided they do shut I may not worry about the perkos not being fire rated. Smoke seals - if its a traditional building with fairly high ceilings and the rooms are occupied and there is full detection throughout again I would probably be ok without them.
Hope this drivel is some help.
