Air conditioning and ventilation duct work in new facilities and new additions shall contain dampers to resist the passage of smoke at each point a duct penetrates a smoke partition or floor level; such ducts shall close automatically upon the detection of smoke. (Exception: this rule does not apply for duct work which is part of a smoke detection or smoke management system.)     
     Source Note:        The provisions of this §263.20 adopted to be effective December 19, 1994, 19 TexReg 9526.