if you ever need the rest down a fire escape regs when a spiral escape wont allow it.
you can use the 5 step landing fire escape like this with landings
it also gives you a wider step which can also be requested by the planning department
we tend not to use them much here in the uk but if built in sections for replacement and also used for water gas and electric supply points they are a good thing to have on the side or rear of the building