No one should ever have to exit a part of the building and then re-enter another part just to operate a call point.
Many boiler houses these days are integral to a building, but with access only from external to the rest of the building and I would assume that the fire resistance from the boiler house to the rest of the building is very high.
However, whilst it might seem unlikely that the person in a smallish boiler room wouldn't be able to exit quite quickly in an emergency, the need to be able to raise a fire alarm warning signal is surely important. It is likely that a fire in a boiler house could quickly become a serious problem, due to the close proximity of fuel etc., and I see the need to quickly warn others to evacuate the rest of the building in the event of a fire in the bolier house as important.
For my part, I consider these sort of boiler houses need the relevant automatic detection and at least one manual call point (all allocated on their own fire zone if the boiler house can only be accessed external to the main building) and at least one audible and one visual warning device (because boiler houses can be noisy).
