Yikes
SAWHORSE
Glennman, I see what you're saying, and your example from the vocational school is a perfect real-world scenario. The 1/2" hole in the floor may sound like a stretch, but it neatly fits the actual problem: a floor surface that is inadequately designed to support a reasonable load.
And you CAN have a curb within the space of a floor area, as long as no one is intended to travel across the curb. (A built-in seat is a type of giant curb.) The fact that the curb would be close to the perimeter of the seating area at the vocational school would make it an unlikely path-of-travel or trip hazard.
Your curb example is not that far off from the description of a baseboard, which is not a walking surface but is a maintenance / wall finish device.
And you CAN have a curb within the space of a floor area, as long as no one is intended to travel across the curb. (A built-in seat is a type of giant curb.) The fact that the curb would be close to the perimeter of the seating area at the vocational school would make it an unlikely path-of-travel or trip hazard.
Your curb example is not that far off from the description of a baseboard, which is not a walking surface but is a maintenance / wall finish device.