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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)."
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
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.
HOWEVER, it can only filter particles down to 200nm, which is good enough to get just about all bacteria and some viruses. But, this new one filters down to 15nm which covers just about everything. Slap a charcoal filter on it to absorb toxins, and it sounds like a hell of a water system.
Still, you can have my Pocket filter when you pry it from my cold, dead, dysenteric fingers. ;)
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
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
The LifeStraw filters particles from 125 micron down to minimal 15 micron
.015 microns
The Lifesaver Bottle cuts out everything larger than 15nm. 15nm =
So yes, this is new news.
www.joshferguson.org
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.
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.
Well, New Orleans wasn't "built" below sea level, it just sank to that point... When it was constructed the land was chosen BECAUSE it was the highest land near the mouth of the Mississippi. The problem is the weight of the city has caused the land to sink over time, resulting in it actually being BELOW sea level currently.
As an aside, carrying condoms in your wallet is generally a bad idea if you plan on using them for their intended goal - but since this is /. after all, I doubt anyone here has much of a use for one. An unlubricated condom in your wallet is a great way to collect urine, or transport water back to your fire. For anyone who spends time in the wild, a simple unlubricated condom or two in your survival kit is a great, and often overlooked, thing.
While this distinction seem important, it really isn't. Most people who are getting sick from bad water, is not getting sick from viruses. Most people getting sick from water aren't even getting sick from bacteria, they get sick from parasites. Furthermore, bacteria and viruses aren't usually swimming alone in the water. Usually they cling to each other, or to other particles, forming what is known as "biofilms". Thus, even a filter with larger pores will filter out most of the harmful organisms, even if the pores are much larger then the organisms you look out for.
A water filter that has smaller pores need more time (or pumping force) to filter the same amount of water. There is no silver bullet. Your filter is either good, or fast. You can't have both.
And saying your filter is "good for 4000 liter" is completely useless. Does it mean 4000 liters of already-clean tap-water, 4000 liter of somewhat unsafe water, or 4000 liter of disgusting feces? Does it mean that after 4000 liter the filter is completely clogged, or does it mean that after 4000 liter the filter is only half as effective in letting water through as when it was new? Besides, what maintenance does the filter need in order to be useful for 4000 liter? Can additional maintenance prolong the life even further?
But there's more. Chemical treatment (e.g. iodine) kills small organisms (e.g. viruses) fast, but takes a long time to kill the larger parasites. So by combining a large-pored (i.e. fast, cheap) filter with chemical treatment (2-5 drops of bleach per liter, or iodine pills if you don't like to taste bleach), you get the best of both worlds: fast and safe.
I hate to say it, but your father is just plain wrong about drinking urine.
So says the US Army Field Manual. So says the SAS Survival Handbook (no link, but page 494). So says Dr. William Elfarr, former head of the Texas Urological Society. So says Master Sergeant Gary L. Benton, survival instructor to B-52 crews. So says Tom Brown Jr., survivor school founder and instructor. So says Equipped.com, a survival site. So says Adventure Sports Online in its 5 basic survival tips. And on, and on, and on.
Your body is getting rid of urine for a reason. Urea is toxic, and the saline component of urine means that it dehydrates instead of hydrating.
Then the winter came, and the Grasshopper died. And the Octopus ate all his acorns. Also, he got a racecar.