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by hopeless 2950 days ago
Practice spotting someone drowning from real videos of public swimming pools: http://spotthedrowningchild.com/

It's good but not perfect since the lifeguard thankfully rescues them before they drown but it's still a good exercise. I can do this exercise fairly reliably but I'm not perfect either.

A few years ago I saved a man from drowning _but_ I very very nearly didn't: https://medium.com/@ideasasylum/i-saved-a-man-from-drowning-...

5 comments

Seems insane to allow non-swimmers to use floating tubes that can flip over without also wearing personal flotation devices.

Even with a lifeguard, what if multiple people need saving at the same time, or the lifeguard just doesn't notice it after a long time with no interventions require.

>"Seems insane to allow non-swimmers to use floating tubes that can flip over without also wearing personal flotation devices."

Years ago I worked as a lifeguard at a public pool where the policy was no flotation devices unless you proved yourself a capable swimmer (able to confidently swim 50 yards.) The rule seemed counter-intuitive for a lot of people, but I'd say it worked well. We never had any flotation-related incidents.

Nonswimmers needed to stay in the shallow end (where to be sure there was still a drowning risk) and because they had to not use any floats, the chance they'd panick was reduced (panicking usually happens when conditions suddenly change, such as when somebody falls off a pool noodle even if the water is shallow enough to stand up.) Taking floats away from non-swimmers, as well as some other common sense policy such as no rough-housing, greatly reduces the chance of anything going wrong.

I remember experiencing exactly that failure mode as a kid-- slipping off of a floatie in the deep end before I was a confident swimmer and needing to be rescued.
I think you're jumping to conclusions that they are non-swimmers.
Not the OP, and I've only watched ~8 of those videos, but it seems pretty safe to say they are non-swimmers. Is there a reason you think I'm jumping to that conclusion?
On what basis do you assume they are non-swimmers? The video doesn't show them swimming - well sure they were in a tube of course it doesn't show them swimming. Just because you can swim fine doesn't mean you will do so when you flip unexpectedly out of a tube when the panic response takes over.

One (the first one I saw when opening it again) where the drowner is never using a float: https://www.youtube.com/watch?v=iXFgOBjk860

The second one I saw he appears to intentionally be leaving the float to go swim so at least thinks he is capable of swimming: https://www.youtube.com/watch?v=NycwxaU4GPw

And for completeness, the third one I saw: are you seriously suggesting that you can judge someone's swimming ability from her response after this flip? https://www.youtube.com/watch?v=STY8N-33-tQ

With respect to that last example: a flip like that can be very disorienting, and even a skilled swimmer can be imperiled like that if they fail to disentangle their legs. She did manage to free her legs and right herself, but at that point in her panicked state she failed to tread water. I would say she was a poor swimmer, if not a nonswimmer. Possibly able to swim while under normal ideal conditions but forgot how to when disoriented. It's not impossible but it seems very unlikely that she was a skilled swimmer.
Let me be clear:

- Once you start drowning, you don't look like a good swimmer no matter if you're Phelps or not

- Videos selected specifically to have people who start drowning in them will show people at their absolute worst swimming moment

- You do not have to be a poor swimmer to start drowning at your worst moment

- There is no reason to think that the drowners wouldn't have passed a "do three laps in the pool and tread water for N minutes" type test

- Requiring a basic swim competency before being allowed to use floats will no doubt reduce the risk of these incidents and is reasonable to do regardless

If you saw a video of a car crash, would you assume that driver had not taken driver's ed? Or rather that they were careless or caught by surprise or had a malfunction or hit a sudden patch of ice or even were intoxicated?

If the lesson you took from this was "this pool was irresponsible in allowing these obviously terrible swimmers in" then you got completely the wrong message. Please don't take the fact that your kid passed her swim test at Girl Scouts to mean that she too won't flip off a tube suddenly, gulp in water down the wrong way and be overcome by our animal instincts. Such an assumption is literally dangerous.

>And for completeness, the third one I saw: are you seriously suggesting that you can judge someone's swimming ability from her response after this flip?

Yes. A thousand times, yes. That is not a strong swimmer.

Please explain why you think that! You literally just see her sitting on a tube, fall over while shrieking and then start drowning because she probably swallowed water the wrong way while shrieking and falling into the water. At that point, it's game over, doesn't matter how good a swimmer she is because she's literally not in control of her body.

Edit: to be clear, I agree that she's very unlikely to be a local swim champion or something. What I am claiming is that even a standard knows-how-to-swim 9 year old can start drowning like that.

From your essay:

> rescuing drowning victims is how good swimmers drown

This, absolutely. People are heavy; drowning people can and will drag you with them due to the instinctual response. Even a child can be quite dangerous to rescue if you're untrained. Call the lifeguards if you see someone drowning, especially if you've never taken any form of lifeguard training.

Well that page is scary. I don't want to admit how much I had to rewatch the first video until I figured someone bonked themself with a damn floating donut and almost drowned. And even then I was at like 3 of 8-10.
I watched all of these videos a few years ago.

After a while, you start noticing a trend.

They also have a cool first person view one:

https://www.youtube.com/watch?v=5sf0Zv52mKQ

Wouldn't this be a really good application of machine learning? Not as a replacement for lifeguards, but to help them.
> "Not as a replacement for lifeguards, but to help them."

You'd need very careful lifeguard training for such a system at the very least. If it worked 95% of the time, a lifeguard may become complacent with manually scanning each swimmer.

I'd wager the most effective measure is hiring redundant lifeguards and encouraging them to keep each other honest. Have overlap in each lifeguards area of responsibility, and cycle lifeguards through different posts a few times per hour to combat fatigue. Of course this costs more, but frankly lifeguards are damn cheap when you consider the importance of their job.

That's a great point, certainly you wouldn't want to breed a culture where the life guards were playing cards back in the staff room with one ear cocked for the "silent sentry" going off to warn of a drowning.

I'd probably deploy it as an almost invisible thing that the staff never interacted with, and dial its detection way down until it virtually never gave a false positive, even if that meant it missed 20% of the actual drownings (those people are no worse off). Anything to avoid complacency, even one false alarm every couple of months would be too much.

The UI would be an earsplitting siren followed by a Robocop like voice shouting e.g. "someone is drowning in lane 5, 50 meter point".

People would try to troll the system and trick it into sounding false alarms.

It's still a good idea, but just an idea at this point. There would be lots of challenges to make it work.

It already exists, can't remember from where though. Some company from Netherlands mabe:

https://www.navet.umea.se/english/navet/sidor/planyourvisit/...

Personally I find it a bit suspect.