34 Pa. Code § 47.221
The following words and terms, when used in this subchapter, have the following meanings, unless the context clearly indicates otherwise:
Balcony—A working platform projecting from a wall.
Handrailing—A single pole, bar or pipe supported on brackets from a wall or partition.
Oiling platform—A raised flooring constructed for the purpose of oiling machinery.
Platform—A raised working floor or stage.
Railing—A vertical barrier erected along the exposed edges of open-sided floors, working platforms, runways, balconies and openings in walls, floors and ground levels.
Runway—A stationary incline or ramp provided as a means of ascent and descent from one level to another.
Toeboard—A board or plank set on edge immediately under a railing at floor level.