Metal stairs are commonly used for industrial applications such as warehouses, loading docks, manufacturing plants, etc. Because these applications are workplaces, OSHA must regulate them for employee safety; roof access stairs, crossover stairs, loading dock stairs, in-plant office stairs are all common types of stairs that OSHA regulates. These types of metal stairs are considered fixed stairways, and they follow the regulations described below.
Platforms / Landings
Platforms can be placed at the top, middle, or bottom of a set of metal stairs.
- Width: Platforms must be at least the width of the stairs. (1910.25(b)(4))
- Depth: Platforms must be at least 30 inches deep, as measured in the direction of travel. (1910.25(b)(4))
- Door or gate present: The door or gate must open up onto a platform, and the swing of the door does not reduce the platform’s depth to 1) less than 20 inches for platforms installed before January 17, 2017 or 2) less than 22 inches for platforms installed on or after January 17, 2017. (1910.25(b)(5)(i) & 1910.25(b)(5)(ii))
Guardrails & Midrails
As an employer, there is a duty to have a fall-protection system in place when there is an unprotected edge that is 4 or more feet from a lower level; guardrails are the most common fall-protection system used for stairs.
- Step Guardrail Height: Unlike ADA guidelines, the guardrails in OSHA steps also act as the handrails when the top edge of the guardrail is between 36 and 38 inches above the leading edge of the stair tread. (1910.29(f)(1)(iii)(A))
- Platform Guardrail Height: The top edge of the top guardrail must be 42 inches, plus or minus 3 inches, above the walking surface, measured vertically from the step tread. (1910.29(b)(1))
- Platform Midrail Height: A system must be put between the steps and the top guardrail to prevent an employee from falling through. Midrails are commonly used in conjunction with the top guard rail. The midrail must be installed at a height midway between the top edge of the guardrail and the walking surface. (1910.29(b)(2))
The step tread is the part of the stairs that you walk on. It can be made from a multitude of decking materials that offer various degrees of traction.
- Tread depths must be the same between each landing platform. (1910.25(b)(3))
- The minimum tread depth is 9.5 inches. (1910.25(c)(3))
- The minimum tread width is 22 inches between the stringers. (1910.25(c)(4))
Risers make up the vertical area between step treads. Risers can be solid or open-back depending on the required compliance code. OSHA does not require solid risers, so most companies choose to have open-back risers because that style is typically less expensive.
- Riser heights must be the same between each landing platform. (1910.25(b)(3))
- The maximum riser height is 9.5 inches. (1910.25(c)(2))
Flootplates are bolted into the ground to secure the stair system.