Obstruction Markings within interior exit stairways of high rise buildings are required by the following building and fire codes:
IBC/IFC 2009, 2012 section 1024.2.5
IBC/IFC 2015 section 1025.2.5
NYC LL 141 Section 1024.2.5
NYC LL26 RS 6.1 Section 2.2.5
NFPA 101 section 22.214.171.124.5.5
Obstacles at or below 6 feet 6 inches (1981 mm) in height and projecting more than 4 inches (102 mm) into the egress path shall be outlined with markings not less than 1 inch (25 mm) in width comprised of a pattern of alternating equal bands, of luminous material and black, with the alternating bands not more than 2 inches (51 mm) thick and angled at 45 degrees (0.79 rad). Obstacles shall include, but are not limited to, standpipes, hose cabinets, wall projections, and restricted height areas.