FORTRESS Calculator

Simply input the rise of your landing into the FORTRESS Calculator and it will tell you which FORTRESS® OSHA Stair System model you need for your application and what position you should set the stair system at.

FORTRESS Positioning

Both models can be set at two different positions, one with the top step level with the platform and one with the top step one riser height below the platform. At these two set positions, a height range is attainable due to the independently adjustable platform and riser legs. This design not only allows for easy, on-site leveling, but also allows the stair system to be set at a different height when moved to a new location.

FORTRESS models available:


  • 3-step System
  • Ranges from 23" to 34" high (OSHA Compliant at 25.5" and 34")


  • 4-step System
  • Ranges from 27.5" to 42.5" high (OSHA Compliant at 34" and 42.5")
View models

How to use the tool:

  1. Measure the distance from the landing to the ground (rise).
  2. Enter the measured rise into the FORTRESS Calculator. Be sure to select inches or centimeters.
  3. The calculator will pair you with a FORTRESS model fit for your rise and will show you the ideal stair and leg position.

CAUTION: Note that not all positions of the FORTRESS are OSHA Compliant.


FOR2334 is OSHA compliant at 25.5” and 34” || FOR2742 is OSHA compliant at 34” and 42.5”

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Questions about our products or need a custom solution? We'll find what works best to meet your needs.
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