Guest Column - October 2008
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Pools/Aquatics: Avoiding Entrapment

The Impact of the Virginia Graeme Baker Pool & Spa Safety Act

By Dennis Berkshire

The Virginia Graeme Baker Pool and Spa Safety Act section 1404 addresses public swimming pools and spas. Per this section:

  • Each public pool and spa in the United States shall be equipped with anti-entrapment devices or systems that comply with ASME/ANSI A112.19.8 performance standard or any successor standard.
  • Each public pool or spa in the United States with a single main drain other than an unblockable drain shall be equipped, at a minimum, with one or more of the following devices or systems: a safety vacuum release system, suction-limiting vent system, gravity drainage system, automatic pump shutoff system, drain disablement, or other system determined to be equally effective as or better than one of these systems.

As noted in the Pool and Spa Safety Act the ASME/ANSI A112.19.8-2007 standard establishes minimum standards for construction, configuration and testing to ensure that a pool or spa main drain does not pose a suction entrapment hazard. This standard requires that the drain must be tested and certified by a nationally recognized testing lab. The standard requires that a main drain is configured such that a tool is required for disassembly of a suction fitting. Slotted screws are not permitted. The screw must have a corrosion resistance to the intended environment equivalent to grade 316 stainless steel. The screw must be installed with no less than three threads of engagement. The drain screws and screw receivers shall be designed for a minimum of 15 secure insertions, tightening and removal cycles with any stripping or failures. The drain fitting must pass tests for structural integrity, ultraviolet resistance, body entrapment, hair entrapment, finger and limb entrapment.

The ASME/ANSI A112.19.8-2007 standard also provides for field-fabricated main drains. A field-fabricated drain outlet must have a spacing from the top of the suction pipe to the bottom of the drain grate of not less than 1.5 times the diameter of the pipe. It must also be operated in a worst case at not more than 1.5 feet per second water velocity through the grates. If the grate is a single main drain, then it must be sized so that it cannot be completely covered by an 18-inch by 23-inch body blocking element and will not cause a differential pressure that could cause body entrapment. In the absence of this configuration, a minimum of two or more drains are required that are separated by no less than three feet. The two or more main drains should be hydraulically balanced so that a pressure differential cannot create an entrapment hazard. Field-fabricated drains that operate at less than 1.5 feet per second are not required to have a hair entrapment test certification.

Even if a pool is designed and constructed with two or more main drains that are at least three feet apart, and plumbed in a hydraulically balanced fashion, the only way to confirm that a main drain or main drain frame and grate meets the ASME/ANSI Standard is to have a drain tested and certified by a nationally recognized testing lab. The standard requires that all main drains be labeled with information including designation that the drain has been tested and certified, the certified maximum flow rate for the drain, the intended application for the fitting, the manufacturer's intended life of the drain and more.

Various nationally-recognized testing laboratories have only recently been set up to conduct tests to the ASME standards. At this time, the National Swimming Pool Foundation (NSPF) reports that there is only one 8-inch diameter drain that has been certified to meet the ASME standard. There are several other manufacturers that are submitting their drains for testing and certification. One of the problems that the manufacturers are having is the ultraviolet (UV) structural testing. The temperatures that the drains must be tested for during the UV tests have proven to be problematic for some materials such as polyvinyl chloride (PVC). Unless the ASME standard can be modified, the drain manufacturers must find alternate materials that can comply with the ASME testing protocol.