Suction Entrapment

Suction entrapment occurs when a person or a thing becomes stuck on a suction port in a pool or a spa.  It can result in serious injuries or even death so should be taken very seriously. It is possible for a person of any age to become trapped against a suction port, but children are much more susceptible because of their lack of strength to break away.

How Does Suction Entrapment Happen?

When a pump is sucking water through multiple ports at the same time (spa, skimmers, and pool main drain) ,  entrapment rarely occurs because the suction force is divided and very weak.

However, when all of the force of the pump suction is concentrated on one port, that suction is very great and has in multiple cases been strong enough to cause disembowelment and/or drowning to the victim.

A pool that has a missing main drain cover may have very weak suction through that port one day that is not very dangerous, and then the next day that same port may have deadly suction because the valves have been adjusted to different positions.

Protect Yourself and Others!

  1. Never swim near the suction ports of a pool or spa. The main suction port of a pool or spa is  at the bottom and should have a protective cover attached securely over it. It is often referred to as the main drain. Hair, jewelry, swimming suits and body parts can become suctin entrapped.
  2. If you see that the main drain protective cover is missing, loose or broken at any pool or spa, immediately exit the water until the problem is fixed.
  3. Check any wall ports in an unfamiliar pool or spa to see if they could be suction ports.   These ports are used for attaching a vacuum and should have a safety cover over them. To check a wall port for suction, make sure the pump is running properly.  Then hold something like a tennis ball (an object too large to go down the hole) over the hole and see if it is sucked against the wall.  Don't use your hand as the object! If the object is not sucked up against the port being tested, it is safe.  If you find such an unprotected suction port in a pool or spa, have everyone exit the pool until the problem is resolved.
  4. Even when the main drain protective cover is securely in place, it may still not be able to protect against suction entrapment.  Older style main drain covers are perfectly flat and a swimmer can still experience suction entrapment on top of that cover.  New style main drain covers are designed with curves that prevent that possibility. They are VGB compliant .....(more about VGB below).
  5. Make sure all pool visitors know where the safety pump shut-off switch is in case of suction entrapment emergency. Shutting off this switch could save someone's life.
  6. Never swim alone.
  7. Keep the pool and spa access locked to prevent unsupervised use.

Below is a photo of a main drain needing a new cover. Danger!

The Virginia Graeme Baker (VGB) Pool and Spa Safety Act

The VGB Act was passed by Congress with the support of the APSP and its members. The Act imposes requirements for all drain covers, and requires retrofitting of all public pools and spas. The Act also encourages each state to adopt entrapment avoidance laws for residential pools and spas, and barrier requirements to prevent drowning.

Several examples from Amazon.com are pictured in the product links below.



Main drain covers that are VGB compliant always spread out the suction holes on the cover in such a way that suction entrapment is avoided.


Pictured below are some other suction port protection fittings. The first item is a spring loaded cover for use on wall vacuum ports.



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