Feature Article - January 2005
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Potentially Dangerous When Wet

Aquatic risk management red flags

By Stacy St. Clair


Pool entrapment is not new. The warnings have been around for years. Yet it remains a senseless—and wholly preventable—tragedy.

An estimated 126 entrapment cases took place between January 1990 and October 2003, according to the latest figures from the Consumer Product Safety Commission (CPSC). Of those incidents, 25—roughly 20 percent of all entrapments—resulted in death.

Aquatic centers and waterparks have a moral obligation to ensure their drains will not snare patrons. The precautions will not only save lives, they are part of any thorough risk-management plan.

The protections, among other things, include making the right design decisions. Dual drains, if spaced and plumbed a sufficient distance from each other, minimize entrapments because bathers cannot block both drains.

Some pools use so-called anti-entrapment covers that prevent arms and torsos from blocking the cover. Others eliminate direct suction outlets from pools and spas by installing a gutter system or surge tanks.

Aquatic managers also can reduce risk with properly engineered and maintained atmospheric vents, which break the vacuum at the suction outlet once entrapment occurs. Release systems also may provide relief from certain kinds of entrapment.

Once the mechanics are in place, pool operators still have major responsibilities. The National Swimming Pool Foundation (NSPF) advises paying close attention to spas and wading pools, where bathers are at greater risk because they're closer to the suction outlets in shallow water.

Among the top priorities is ensuring the drains don't become clogged and drain covers are properly installed. No pool or spa should ever be opened if the drains are missing, damaged or secured incorrectly.

Drain covers also should display markings for maximum flow rates, model number and proof of third-party testing, according to the NSPF. They also should be installed so that the maximum flow rating is not exceeded, making the drain more susceptible to entrapment and hair entanglement.

Operators also should check frequently with the CPSC for any advances or new recommendations for preventing entrapment. Updates can be found at the CPSC Web site, www.CPSC.gov.


The National Swimming Pool Foundation recognizes five types of entrapment, all of them potentially life-threatening.

Here are the five categories:

  • Hair entrapment: Occurs when long hair passes through the suction outlet and entangles itself beyond the cover. The suction pulls the head to the cover and locks it there. There were 40 hair entrapment incidents between 2001 and 2003, according the Consumer Product Safety Commission. Of those, 11 resulted in death.
  • Limb entrapment: Occurs when a drain cover is missing or broken. Suction pulls a limb—leg, arm, knuckle finger or toe—into the plumbing.
  • Body entrapment: Occurs when the body is held against the suction outlet and forms a seal. Fourteen deaths occurred from body or limb entrapment between January 2001 and October 2003.
  • Disembowelment: Occurs when buttocks seal a suction outlet, causing the rectum to burst and viscera to be pulled from the body.
  • Mechanical entrapment: Occurs when something attached to the bather—necklace, earring, bathing suit—becomes entangled with equipment below water.