1023.12 Smokeproof enclosures. Where required by Section 403.5.4, 405.7.2 or 412.2.2.1, of the International Building Code, interior exit stairways and ramps shall be smokeproof enclosures in accordance with Section 909.20 of the International Building Code. Where interior exit stairways and ramps are pressurized in accordance with Section 909.20.5 of the International Building Code, the smoke control pressurization system shall comply with the requirements specified in Section 909.6.3 of the International Building Code.
Wash. Admin. Code § 51-54A-1023