The International Residential Code, IRC, requires that you provide safety glazing (tempered glass) in all windows within 36″ horizontally and 60″ vertically above a stair walking surface.
We did a project on a older loft building with large, existing glazing that the owner was not able to change out to tempered. He asked us to find an exception.
One way to get an exception to this code is to install a protective bar instead of the safety glazing. the bar must be 34-38″ above the floor. It must be a minimum of 1.5″ high and able to withstand 50 lbs per linear foot without contacting the glass.
This was a useful exemption and not something that would have worked in a commercial occupancy. The safety glazing portion of the code is very lengthy so ask questions.
