Interior Exit Stairways And Ramps Enclosures Fire Resistance.

Interior Exit Stairways And Ramps Enclosures.

Interior Exit Stairways And Ramps Enclosures . must be constructed as fire barriers according to Section 707 of the IBC, or as horizontal assemblies according to Section 711 IBC , or both.

Fire-Resistance Rating of Enclosures for interior exit stairways and ramps

1. Not less than 2 hours if connecting four stories or more.
2. Not less than 1 hour if connecting less than four stories.

Termination. 

Interior exit stairways and ramps shall terminate at an exit discharge or a public way.

Note:

1. The number of stories includes any basements but excludes mezzanines. The fire-resistance rating of the interior exit stairways and ramps should not be less than the floor assembly being penetrated, but it doesn't need to exceed 2 hours.
2. If a stairway or ramp does extend below the level of exit discharge, it must be equipped with an approved barrier at the exit discharge level. This barrier serves to prevent people from inadvertently continuing their descent into lower levels of the building.

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