In case of fire, use elevators.” It sounds like apostasy, as if a lifetime’s indoctrination had suddenly been invalidated. But it is exactly the instruction that office workers in New York’s tallest skyscrapers may receive in coming years. The fire department, buildings and city planning departments are planning occupant-evacuation elevators — cars that can, in special circumstances, be used to move people down in an emergency.

That would upend the decade-old notion that elevators are perilous and undependable in fires or other emergencies. Experts also believe that building evacuations have become outmoded as extremely tall skyscrapers increasingly pierce the New York skyline. “We have to find a better way to evacuate people from high-rise buildings, including people with disabilities,” Edward T Ferrier, the deputy assistant chief of fire prevention, said.