Each swimmer at a public pool would be given a bracelet when they arrived which contained a pressure sensor and a small radio transponder. An electronic monitoring system would 'ping' all the transponder bracelets every few seconds to listen for which ones were above water. To allow for people who go underwater for awhile and only surface briefly, the system would ping more frequently any transponder bracelets which hadn't been heard from in over 30 seconds. If a transponder bracelet went more than 60 seconds without establishing above-water radio contact, it would start to vibrate or beep audibly to request that the wearer raise it to the surface and a light would illuminate on the lifeguard's console. After 90 seconds without contact, alarms would sound on the bracelet and the lifeguard's console.
Seem feasible?-- supercat, Jan 26 2002 Might be a lot of false alerts from runs to the bathroom and the inevitable jokesters who steal them.
Make the bracelet responsible for 'listening' (rather than responding to a query). After 45 seconds, it vibrates. After 90 seconds of not hearing the transmitter, it could flash a strobe light and make a high pitched chirping noise. This would also disuade theives.-- phoenix, Jan 26 2002 If you're just standing up in a 4-foot pool, with your head comfortably over water, won't your hands be under water? If it were built into goggles, it would work.-- jutta, Jan 26 2002 My Pop's last day on the job as Fire Chief:Responded to Pool Drowning of toddler - the residence was the very first residence on outskirts of adjoining city - which had several EMT Capable Fire Stations (EMTs which Pop had trained, he initiated/taught CPR etc. Countywide) in closer proximity to residence than the County Station he was at. The Residence was at the furthest reach of County lines of so-called jurisdiction. The godforsaken system is such that geographical boundaries, not true time/distance are the rule. Time is of the essence in anything involving internal passageways. To make a long story short, the mother of the child was a nurse at the very same hospital where the child was transported with my Pop giving his all to make that child live again on the entire ride - which was escorted in the lead by the Father of the child, who was a Sheriffs Deputy. The child had stopped breathing long before my Father got there, and he did everything in his power to revive that life. He continued trying for another half hour after they were at the hospital. Everybody knew him there - he had revived many people - This time the doctor told him "I'm sorry, he's gone." He stopped, looked at the time to confirm pronounced time of death - As it was, my Pops shift was scheduled to end that day at noon. It was 12:30 - his career was over. If there is any one thing I wish for my Pop, it's for something/anything like this to have been around, so he and the parents wouldn't have to re-live that day. And you know they do.-- thumbwax, Jan 26 2002 jutta: That's why there's the 'mild' beep after 60 seconds before the thing sounds the alarm. Someone standing as you describe would just have to lift their arm briefly when the thing went off.-- supercat, Jan 26 2002 I want it to work without the operator doing exercises just for the thing's sake.-- jutta, Jan 27 2002 What about the 'polar opposite' of a mercury switch?-- thumbwax, Jan 27 2002 Bone. Good idea, bad system. Suggested modifications:
Don't use bracelets. Don't use anything on the people. Most drownings occur when there are no other people present. Having a lifeguard and 30 or so people is usually safety enough.
Something that can detect PEOPLE in the pool is what you want. Perhaps any kind of device capable of sensing motion underwater would do. An adult going for a swim could turn the detector off. A child slipping in unannounced would not be able to. Cuts down on miscreants and drownings in residential pools.-- ye_river_xiv, Jul 30 2006 random, halfbakery