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"Lifesaver Bottle" Filters Viruses Out of Water
gihan_ripper writes "British inventor Michael Pritchard has developed a small self-contained filter system that instantly cleans water, removing all particles larger than 15nm. He said that he was inspired after seeing the effects of Hurricane Katrina and the Boxing Day tsunami in 2004; people had to wait for many days to get fresh water and many died from drinking contaminated water. The filter is so effective that it can purify dirty river water and even fecal matter. His bottle will shortly be available for sale from Lifesaver Systems at an expected cost of £190 (approx. $385)."
Fantastic idea, except for the fact that anyone in the path of Katrina who could have afforded a $385 water bottle could have afforded a $90 plane ticket, $35 bus ride, or $27 tank of gas.
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No shit!
More than one year ago, BBC mentioned the LifeStraw that filters water as you drink. It's able to filter 700 litres of water and was at that time priced at less than two quid (probably the wholesale price). See also the inventor Torben Vestergaard Frandsen's website.
Unselfish actions pay back better
It's been possible to buy similar "virus level" filters for hiking since at least the 80s. The typical problems are cleaning, and clogging. See Katadyn or your local REI for a variety of samples. Then there's the "$2" (really about $7) LifeStraw, that was advertised on gizmodo 2 years ago... is this just a running theme?
If the filter is small enough to block viruses, then it is so small that even very small 1u particles will clog it. The whole filter system has to be optimized... and they still clog. They claim 1000 liters, but I'm not really buying it. If it really has something to do with distilling, then I'd be more positive, but that's usually pretty darn complex.
Perhaps he's using a teflon reverse osmosis filter? At the price, it's certainly possible. Those take significant pressure, but they would take out viruses. The water has to start pretty clean too or they develop a film which clogs them too. People have tried iodine on them as well... it works for a while. Whithout knowing what this thing is (and the website's no help), I don't think we can really talk coherently about it.
If it is just a filter you can reverse flush and clean and do a variety of other things, but if your filter clogs after a few liters you'll be _very_ unhappy. This is made more difficult by the fact that you're trying to clean out biologicals, which will happily grow in the filter so it clogs up even quicker, and the cleaning is even more important and difficult to do completely. That's why people make throw aways or just add a halogen (chlorene/iodine) to a tub of relatively filtered water (so things can diffuse) and wait an hour.
Most hikers (who bother) use a more coarse filter (for bacteria only). Often these are treated with iodine as well, and perhaps charcoal to remove bad tastes. These keep clogging problems down, and make cleaning somewhat more easy. That's what the LifeStraw is based on.
I hope this is really an advancement, but it has the smell of an ad.
This actually takes quite a while; for most people, urine is upwards of 98% water. Sure, if you drink nothing but urine for months you may develop problems -- but if you're stuck somewhere and water is in short supply, you should definitely drink your urine. It only takes the average human 3 or 4 days to die of thirst, and if you don't know when help will arrive, don't risk it.
You need 2 buckets, a cotton t-shirt, propane camp stove ( or a heat source to boil water of some kind ) and bleach.
Cover the mouth of the empty bucket with the cotton t-shit.
Fill the other bucket with suspect water.
Pour the water from the full bucket into the empty bucket through the t-shirt. This filters out the larger baddies.
Presuming at least one of the buckets is metal, you can boil water in that. If not, a pot of some sort is required. The idea is to boil the water to a rolling boil for at least one minute.
Allow the water to cool for at least 30 minutes. Once cool, add 16 drops of bleach per gallon ( or 8 drops per 2 liter bottle ). If the water smells faintly of chlorine, it's safe to drink. If not, repeat adding the bleach.
Thanks to the Red Cross for directions.
A $400 water filtration system is nice, and can be cost effective in some cases ( as others pointed out, shipping and distributing small empty bottles is easier that shipping and distributing water ), but not having one doesn't mean you have no options.
A Human Right
I wholeheartedly agree. In fact, you should start drinking your own urine, so you get used to the taste, just in case the water suddenly runs out. I know I have!
You'll develop problems much faster than that if you drink your own urine.
98% sounds much, but it isn't. It means that the salinity can be up to 2% - not far from sea water. If you drink it, it will make you dry out faster than not drinking at all. See, that's how the (healthy) kidneys work: the stuff you pee out can never have a lower salinity than the rest of your body.
Drinking pee is harder than you think. I speak from personal experience.
I was lost in the Ozark mountains for 2 days without any supplies. The temperature was over 100F and I had almost no water. The little water I did have was exhausted quickly and the next best alternative was my own pee. I became thirsty enough that drinking my own pee was not even a question - it was a necessity (or so I thought).
I removed my flashlight batteries and peed in my flashlight because it was the only thing I had that could hold liquid.
Guess what happens to your pee when you are dehydrated? It's get much more concentrated. So much so, that I think you'll have a hard time drinking it unless you are, literally, getting close to death. Mine was so strong, I couldn't even stomach the smell much less, drink it. I have never been as thirsty in my life as that day and I have never since, been in a situation as dire as that one. Yet, I couldn't drink it.
While it may be an option early on, as dehydration starts setting in, drinking your own pee becomes less of an option as each hour passes by.
Damn folks still thinking that Katrina only affected New Orleans. Katrina
wiped out entire cities on the Mississippi Gulf coast. Infrastructure
was destroyed for at least 100 miles inland. The military had to **cut**
their way down HWY 49 to reach the coast.
So, to correct your statement, A large percentage of New Orleans problems
were caused, post hurricane, by the failure of the levees. A large percentage
of the problems caused by directly Katrina were actually in Mississippi.
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne