Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

smithsonianmag.com

Post reply on HN
Print view View original

31–40 of 96 posts

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#31

Post by gm-conspiracy »

lbruder wrote: post #18
peterburkimsher wrote: post #13

Are there companies doing wastewater monitoring on pools for public health? All kinds of disgusting things get flushed down toilets in homes and businesses. I think that monitoring a swimming pool would give more helpful data, because the bacteria/viruses/pollutants were all carried by humans.

Working for a water treatment company here. We have created a mathematical model for public pools that includes a projected number of visitors per weekday, the weather forecast, school holidays, and based on that, a daily influx of urine, feces, pus and so on. We use this model to create adaptive controllers that minimize the amount of chemicals used to keep the water safe while actually keeping it safe (work in prog…

Now you just need to correlate your model with the stock market and use Twitter for sentiment analysis.

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#32

Post by tzs »

tomhoward wrote: post #25
arethuza wrote: post #14

Earlier quoted context omitted.

Why are sudden temperature changes bad? When I was a kid in the north of Scotland we'd always jump in as gradual exposure to cold water was miserable - the shock of jumping in was always quite bracing ;-) Mind you - as I doubt if it was much above 20C most of the time I doubt the temperature difference between air and water was that large!

The cardiovascular system has to suddenly adjust its rate to keep the body warm enough. If your heart is weak, it may not be up to the task and a heart attack is possible. It might be fine for young people and people with people with peak cardiovascular health, but for older people or anyone with impaired cardiovascular health, the risk goes up.

Does how you get into the cold water make a difference? Specifically, entering in a way that does not trigger the mammalian diving reflex, such as wading in up to your chest or neck, versus entering in a way that does trigger it, such as holding your breath and jumping completely in?

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#33

Post by stonewhite »

There is a very informative video[1] that also links to scientific papers about this phenomenon and concludes much less sensationally.

Essentially, urine is a sterile substance containing %95 pure water and no living cells or bacteria. Other than the asthma inducing effects of chloramine, swimming at a public pool doesn't pose a massive threat to your health.

[1]: https://www.youtube.com/watch?v=S32y9aYEzzo

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#34

Post by maxerickson »

Cthulhu_ wrote: post #24
sschueller wrote: post #2

That is why you should shower before going in to the pool. At school we were always required to shower before and after. One pool I have been at added a shower you have to go through to get to the pool. It's a continues curtain of water.

> One pool I have been at added a shower you have to go through to get to the pool. It's a continues curtain of water. That's clever, they should install that in more places.

Briefly getting wet isn't a shower though.

A curtain of water isn't going to do much about cryptosporidium.

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#37

Post by [deleted] »

Faaak wrote: post #28
LoSboccacc wrote: post #26

Earlier quoted context omitted.

dunno. seems a lot of wasted water, you can't recirculate it or you'd be back to square one. maybe if it's activated with a pressure plate of sort it'd be more environmentally friendly.

Maybe the water is changed every day. It would still be useful as the large (lets say 2m³) volume of water would slowly begin charging up with contaminants

[deleted]

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#38

Post by Tade0 »

hackandtrip wrote: post #9
sschueller wrote: post #2

That is why you should shower before going in to the pool. At school we were always required to shower before and after. One pool I have been at added a shower you have to go through to get to the pool. It's a continues curtain of water.

Slightly off topic, but you should shower to avoid temperature difference too, specially in hot days. I don't know about the lifeguard situation in USA, in Italy it's pretty terrible; it should be absolutely required to have a shower before jumping in the water.

I don't know about the lifeguard situation in USA, in Italy it's pretty terrible;

Interesting, because my impression was that there's a decent amount of staff comparing to my country (Poland).

Also it's the first place at which I've seen a line of lifeguards on rafts making sure nobody reaches the point where they can collide with motorboats.

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#39

Post by nickjj »

ganonm wrote: post #20

The chlorinates created when the chlorine reacts with e.g. sweat and urine is what causes red eyes and breathing difficulties. From my experience, stay away from hotel/health club pools. These usually have saunas and jacuzzis which means people jump into the pool afterwards and contaminate it a lot... If you are doing swimming for fitness you will be inhaling a much larger volume of air, plus you will be inhaling air…

When you say difficulty in breathing, do you mean that feeling that you sometimes get after being in a pool for a long time where if you take a deep breath, it kind of hurts your lungs?

Re: Urine, Not Chlorine, Causes Red Eyes in Pools (2015)

#40

Post by herbst »

LoSboccacc wrote: post #26
Cthulhu_ wrote: post #24

Earlier quoted context omitted.

> One pool I have been at added a shower you have to go through to get to the pool. It's a continues curtain of water. That's clever, they should install that in more places.

dunno. seems a lot of wasted water, you can't recirculate it or you'd be back to square one. maybe if it's activated with a pressure plate of sort it'd be more environmentally friendly.

I've seen things like these a few times and all were motion activated. However in practice they almost always run because of the amount of people.
Post reply on HN