What is stairwell pressurization?
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.
How is stairwell pressurization accomplished?
Pressurization of the exit passageway can be accomplished in a variety of ways such as the use of air transfer grille(s) in in the walls between the interior exit stairway and exit passageway, installation of ductwork connecting the two areas, or by installation of a separate fan for the exit passageway.
Why is stairwell pressurization important?
In essence, stair pressurization creates a barrier to help control smoke movement in case of an emergency. The higher pressure in the stairwell “pushes” the smoke back into the lesser pressurized hallway, allowing the escape route to be free of smoke.
Are stairwells ventilated?
Vestibules and egress stairs are generally not considered “occupiable” spaces under ASHRAE 62, and therefore would not require ventilation. However, if you want people to actually use the stair, adding ventilation would make it a more attractive option.
What is pressurisation system?
Pressurisation systems prevent smoke from entering escape routes through air overpressure. In the event of a door opening or an air leak, the system reacts by increasing the air flow rate, so that the routes are always free of smoke in an emergency situation.
What is the reason to have a pressurized enclosed stairwell in an apartment high rise building?
Most building codes require the fire stairwells in a high-rise building to be pressurized to keep smoke out. The stairwell pressurization serves several purposes: • Inhibit migration of smoke to stairwells, areas of refuge, elevator shafts, or similar areas.
What is the purpose of lift pressurization fan?
Lift Pressurisation Fans are need of the hour, they are used to pressurise the lift shaft. These Fans play a vital role in safety during a fire. These are Manufactured from heavy duty mild steel material and best in class Impellers to provide optimum pressurised air to maintain positive pressure in lift shaft.
Is stairwell pressurization required?
As alluded to above, we most commonly see stairwell pressurization systems utilized in high-rise buildings. The code simply requires that every exit stair serving floors more than 75 feet above the lowest level of fire department access shall be a ‘smokeproof enclosure.
Why are staircases pressurized during emergency evacuation?
This is by far the most compelling argument for effective smoke control in building stairwells. Pressurized staircases keep exit routes smoke free in the event of a fire, lending precious minutes to building occupants during an evacuation. The pressures specified to keep a stairwell pressure positive vary by code.
What is lift well pressurisation?
Lift Well Pressurization System are intended to prevent smoke from flowing through an elevator shaft and threatening life on floors remote from a fire. Elevator pressurization is an alternative to enclosed elevator lobbies.