Is there a building code calculator for minimum clearance of stairwell ceiling based on stair rise/run etc.

We are finishing our basement, and have turned the stairs half way down. There is a major drain pipe that limits the ceiling clearance in the low part of the stairwell. We could move the pipe.

The lowest point is about 82" from the step edge to the ceiling. I notice it because I'm 6'2". It really comes down to a safety issue. (The steps are code, 7.0" rise, 10.5" run.)
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