The Z iron stairs are typical fire escape stairs in New York City. They were introduced in the mid of 1800s. While the aim of the stairs was as a refuge to escape from the fire, but later on, the stairs also become a haven to escape from the hot summer. When the tenants have no air conditioning in their apartments during the summer, they sleep on their fire escape stairs. Accidents of people fell from the fire escape were reported, and these could result in death.