Stairwell Fire Rating

Q:  We are being told by our local AHJ that a stairwell in a 2 story building has to be 2-hour fire resistance rated so that it meets the requirements of occupancy separation since one floor is healthcare and one floor is business. Do you agree?
A: Well…. That is a matter of interpretation, and I can understand the logic with the requirement to be 2-hour fire rated. Another way of looking at it is if a stairwell was only one hour fire rated, it would take a fire starting on the 1st floor (business occupancy) one hour to penetrate the stairwell barrier, and then it would take one more hour to penetrate the 2nd floor (healthcare occupancy) which is a total of 2 hours. Personally, I would not buy into that line of thought, and if I were an AHJ, I would not allow a 1-hour fire rated stairwell to separate a business occupancy from a healthcare occupancy. I would require it to be 2-hour rated. But, that’s me. Remember… Every AHJ has the right to interpret the Life Safety Code as they see fit.