Final answer:
Any glass at the bottom of the stairs within a 60" arc must typically have a clearance of at least 36 inches, according to common safety regulations, but the exact requirements can vary based on local building codes.
Step-by-step explanation:
The question you've asked pertains to building codes, particularly those relevant to the safety features of staircases and glass positioning. Within the context of the International Building Code (IBC) or similar regulations, any glass that is located at the bottom of a staircase must adhere to specific clearance requirements to ensure safety. This is to prevent injuries that could be caused by someone falling down the stairs and into the glass.
While the exact clearance may vary based on local building codes, a common requirement for glass near staircases is a horizontal clearance of 36 inches (914 mm). This means that the closest point of any pane of glass must be at least 36 inches away from the bottom tread of the staircase within a 60" arc.
It is essential for safety measures to be followed to protect users of the space. It's recommended to check the local building codes for the specific requirements in your area as these can sometimes differ from one jurisdiction to another.