6вЂі sphere - at the triangle formed by riser, tread and bottom rail.4-3/8вЂі sphere for openings on the sides of stair treads.On monumental stairs, handrails shall be located along the most direct path of egress travel. Intermediate handrails are required so that all portions of the stairway width required for egress capacity are within 30 inches of a handrail.All portions of the stairway width required for egress capacity are within 30 inches (762mm) of a handrail.HeightВ Requirements (of Guards) For Balconies, Galleries & Bleachers In assembly seating where guards in accordance with Section 1025.14 are permitted and provided.The height in assembly areas shall be in accordance with Section 1008.12.In those applications, where the top rail also serves as a handrail, it shall have a height of not less than 34вЂі and not more than 38вЂі above stair nosing. 42вЂі minimum except in Group R-3, and within individual dwelling units of Group R-2.34вЂі minimum on the open side of stairs.36вЂі minimum on porches, balconies, raised floor surfaces.HeightВ Requirments, Minimum for Guardrails Measurement for the 30вЂі drop is to be taken at any point within 36вЂі from the edge of the open surface.

30вЂі above floor or grade below along glazed sides of stairways, ramps, and landings where the glazing provided does not meet the codeвЂ™s strength and attachment requirements.30вЂі above floor or grade below on open-sided walking surfaces, mezzanines, industrial equipment platforms, stairways, ramps and landings.On open sides of stairs with a total riser of more than 30вЂі above the floor or grade below.30вЂі above floor or grade below on open-sided walking surfaces.

Irc stair code