PM-307.1 General. Every exterior and interior flight of stairs having more than four risers shall have a handrail on one side of the stair and every open portion of a stair, landing, balcony, porch, deck, ramp or other walking surface which is more than 30 inches (762 mm) above the floor or grade below shall have guards. Handrails shall not be less than 30 inches (762 mm) high or more than 42 inches (1067 mm) high measured vertically above the nosing of the tread or above the finished floor of the landing or walking surfaces. Guards shall not be less than 30 inches (762 mm) high above the floor of the landing, balcony, porch, deck, or ramp or other walking surface.
Exception: Guards shall not be required where exempted by the adopted building code.