One cause of drowning deaths and injuries is entrapment. Entrapment occurs when a person becomes caught in the strong suction in and around swimming pool and spa drains. In some instances, the suction force around drains is so strong that the bather cannot break free and either drowns or is fatally injured before being rescued.
Rules & Regulations
Suction outlets must be designed to produce circulation throughout the pool or spa
Single outlet systems, such as automatic vacuum cleaner systems, or other such multiple suction outlets whether isolated by valves or otherwise must be protected against user entrapment
Suction Fittings: All pool and spa suction outlets (except surface skimmers) must be provided with:
A cover that conforms with reference standard ANSI/ASME A112.19.8 Suction Fittings for Use in Swimming Pools, Wading Pools, Spas, Hot Tubs, and Whirlpool Bathtub Appliances
A drain grate that is 18 inches x 23 inches or larger
An approved channel drain system
Atmospheric vacuum relief system required: All pool and spa single - or multiple-outlet circulation systems must be equipped with atmospheric vacuum relief should grate covers located in the pool become missing or broken
The vacuum relief system needs to include at least one of the following 2 approved or engineered methods:
Safety vacuum release system conforming to ASME A112.19.17; or
An approved gravity drainage system
Dual drain separation: Single or multiple pump circulation systems must have:
At least two of the approved type of suction outlets, and
A minimum horizontal or vertical distance of 3 feet between the outlets, and
The suction outlets piped so that water is drawn through them simultaneously through a vacuum-relief-protected line to the pump or pumps
Pool cleaner fittings: Where provided, vacuum or pressure cleaner fittings shall be located in accessible positions at least 6 inches and not more than 12 inches below the minimum operational water level, or as an attachment to the skimmers