<http://schema.org/keywords>
"ladders, industrial, staircase, stairway, step, ladder, Treppen, Treppe, Stufen, Leiter, escalier, \u00E9tape, \u00E9chelle, escada, degrau"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.bibliocad.com/library/industrial-staircase,-3d_62878>