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Generally denoted by K, the universal constant is used in calculating the proper density and distribution of smoke detectors in a house hallway. While the constant can not be mathematically derived, it's value has been estimated at 150, and has units of square feet/kitchen*staircase.
Dude, to be able to tell you how many smoke detectors you'll need, I need to know the proper universal hallway constant.
by Fire Safety October 20, 2010