What is the minimum size required for a black disk in a swimming facility?

The minimum size required for a black disk in a swimming facility is six inches. The purpose of the black disk is to serve as a visual reference point for swimmers, helping them assess their distances from the pool's bottom and aids in visibility during swim practices and rescue operations. A black disk of this size is large enough to ensure it can be easily seen and identified in the water, particularly under various lighting conditions.

Using a six-inch disk meets established safety standards for aquatic environments, ensuring that it is appropriately sized to perform its function effectively. This specification is important not only for swimmer safety but also for supervisory and lifeguard duties, as it aids in monitoring swim techniques and ensures swimmers can navigate the water safely.