Stair Pressurization Fan & Fire Detection integration

Stair Pressurization Fan & Fire Detection integration

According to the National Fire Protection Association, the process of evacuating some of today’s largest high-rise buildings may take upwards of two hours.  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.  However, the universal goal is to restrain smoke but still allow the opening of doors in the stairwell shaft.

In case of fire in a high rise building, a Stair Pressurization Fan (SPF) uses clean outside air to pressurize the air in stairwells. The pressurized air helps people escape the fire and firefighters battle the fire. It should be work during fire condition through FACP.

When there's a fire, clean outside air is forced by a Stair Pressurization Fan into a stairwell. The pressurization is used to push back on smoke, keeping the smoke out of the escape route.

Stairways are Fire Escape Routes

Nowadays, stairwells have better fire ratings than the rest of the building. In other words, so people can get out when the rest of the building is on fire, stairways don't burn.

Stairways Full of Smoke

The stairways may not burn, but they can still fill up with smoke. The smoke can not only make it harder to see as one is getting away from a fire, but it can:

·        Make it harder to breathe - possibly causing injury or death

·      Close off the escape route - possibly causing people to seek another pathway of escape

Open Doors

The problem is, as people are escaping the fire, they have to open the door to the stairway. When the door is open, preventing the stairway from being used by later escapees, smoke follows and billows into the stairway.

Smoke Push Back

The idea behind the stair pressurization is that during a fire the stairway should have more pressure than the rest of the building. That way, when the doors open, the higher pressure in the stairwell pushes the smoke back onto the floor, keeping the escape route clear of smoke.

The smoke free escape route also doubles as a smoke free entrance route for the firefighters as they combat the fire.

Turning On the SPF

Except when there's smoke, the stair pressurization fans aren't needed, so normally they're turned off. When the fire alarm system detects smoke, they're automatically turned on.

As firefighters battle the fire, if the fire alarm system has not turned on the stair pressurization fans, they're turned on by the firefighters.

Escape

As people are escaping a fire, and open the doors to get into the stairways, smoke would naturally billow from a fire floor into the stairwell. Keeping the smoke out of the stairwell by pushing it back onto the floor, a Stair Pressurization Fan pressurizes the air in the stairwell.

Integration

In every Fire Detection system has one devices named Control Module / Relay Module. This Module operate through FACP loop line. Module has Loop IN /OUT & NO COM NC. Module can be programed as NO / NC condition. An External relay may require (Depend on Module relay capacity) for integration. If Stair Pressurization Fan starter panel has an auxiliary circuit for Fire Alarm then only no need to put any external relay. During external relay operation you required one adjust power supply to energized relay coil.