Shaft

SHAFT, as defined in the Mechanical Code, is an interior space enclosed by walls or construction extending through one or more stories or basements which connects openings in successive floors or floors and roof, to accommodate elevators, dumbwaiters, mechanical equipment or similar devices to transmit light or ventilation air. Shafts and exit enclosures, as defined in the UBC, are areas in a building where stairs run up and down and must be enclosed for fire protection and where utilities and elevators run up and down through the building.