Safety Use of Scaffold Materials: OSHA Requirements on Using Stair Towers
Stair towers are stairways that provide temporary access to a building but are separated from all its floors. To ensure the safety of the workers when using these scaffold materials, the Occupational Safety and Health Administration (OSHA) set standards on their construction and design.
Stair towers are the safe solution for those working in very high buildings. To meet height and safety regulations, they should be installed between 40 degrees and 60 degrees from the horizontal. Except for the top and bottom steps of the entire system, they should have uniform riser height and tread depth. All treads and landings should also have slip-resistant surfaces.
These scaffold products also need to have a stair-rail that comprises a top-rail and mid-rail on each side. Stair-rails must not be less than 28 inches but nor more than 37 inches from the surface of the tread. There must also be at least 18 inches wide between stair-rails.
Unless a separate handrail is provided, the top-rails of these scaffold materials must also be capable of serving as handrails and be at least three (3) inches away from other objects.