Since high rise building will have automatic fire sprinklers, fire pumps, outside siamese connections for the fire department pumper connections, the only oversize equipment will be the firemen with their gears riding elevators. Elevator companies have already established acceptable door sizes to suit the fire department personnel. Check out the NFPA 101 recommendations for acceptable door sizes, your state or country building code and the local Fire Marshall.
There are quite a few requirements for fire service elevators. The most current edition of IBC lists these requirements in Section 3007. Specific opening and elevator lobby sizes are addressed in Section 3007.6.