What is stairway enclosure?

stairway enclosure means the space enclosing interior stairs, landings between flights, corridors, and passageways used for direct exit to the exterior of a building, and any lobbies or other common areas that open onto such direct exits.

What is a smokeproof tower?

In building safety and construction, a smokeproof enclosure is a type of exit stairwell that has been designed to keep out smoke (and other combustion products) in the event of a fire, so that building occupants may more safely exit the building.

Where a Smokeproof enclosure is extended by an exit passageway The exit passageway shall be separated from the remainder of the building by minimum?

The exit passageway shall be separated from the remainder of the building by 2-hour fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 712, or both.

Where natural ventilation is utilized for venting a Smokeproof enclosure each vestibule shall be provided with a minimum?

3.3 Vestibule Ventilation. Each vestibule shall have a minimum net area of 16 square feet (1.5 m2) of opening in a wall facing an outer court, yard or public way that is not less than 20 feet (6096 mm) in width.

Do stairs need to be enclosed?

There shall be no enclosed usable space under exterior exit stairways unless the space is completely enclosed in 1-hour fire-resistance-rated construction. The open space under exterior stairways shall not be used for any purpose.

Do fire stairs need to be enclosed?

Fire-isolated stairways and ramps — If the space below a required fire-isolated stairway or fire-isolated ramp is within the fire-isolated shaft, it must not be enclosed to form a cupboard or similar enclosed space. any access doorway to the enclosed space is fitted with a self-closing –/60/30 fire door.

Which of the following is a limitation of fire resistance laboratory test findings?

Which of the following is a limitation of fire resistance laboratory test findings? Fire-rated assemblies may behave differently in laboratory settings than they do in uncontrolled conditions. The only standardized test method for fire resistance that is universally accepted by building codes is the: ASTM E-119 test.

What is an exit passageway?

An exit passageway is defined as “an exit component that is separated from other interior spaces of a building or structure by fire- resistance-rated construction and opening protectives, and provides for a protected path of egress travel in a horizontal direction to an exit or to the exit discharge.”

How long can an exit passageway be?

NFPA 101 allows a maximum of 150 feet for unsprinklered educational occupancies, and 200 feet for sprinklered educational occupancies. Common Path of Egress Travel – This is the distance that a building occupant must travel before two separate egress paths to two exits are available.

Do stairwells need ventilation?

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.

How does stair pressurisation work?

When the stairwell is pressurised, it has higher air pressure than the surrounding areas. A relief system eases the pressure without letting the smoke enter these areas in your stairwell. People don’t need to use much force to get through doors and access safe egress routes.

What is the code for interior stairs?

International Residential Code (IRC) The IRC stairs code states that, to comply with stairway requirements, the minimum width for residential stairs be no less than 36 inches. The stair riser code is up to 7.75 inches, and can not vary more than 3/8 of an inch.