What is pressurization in fire?

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A pressurization system is intended to prevent smoke leaking passed closed doors into stairs by injecting clean air into the stair enclosure such that the pressure in the stair is greater than the adjacent fire compartment.

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What is the purpose of pressurization?

The intended function of pressurization systems is to provide protection to both building occupants and fire fighters. In high rise buildings evacuation is normally phased such that occupants do not all move to the escape stairs at the same time.