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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)."
http://www.lifestraw.com/
Not to mention urine is usually sterile until it exits the body. The real question is whether the filter will remove any/enough of the waste products that the body is trying to rid itself of to make such a recycling loop acceptable for more than a couple of passes.
It removes all particles larger than 15 nm, but chemical bond lengths are typically 0.2 nm, so this bottle will not filter small molecules such as Urea.
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
Not to mention the fact that hikers and backpackers have used $60 filter bottles for years now that do pretty much the same thing. Not only that, but I already have filter straws with activated carbon in my 72-hour kits. They cost about $10. Another company makes a small battery-powered water filter with a UV light in it to sterilize pathogens.
I'm to lazy to RTFA, but this thing sounds like a ridiculously expensive non-invention. The already existing, less-expensive technology might not get virii out, but you're generally not concerned with virii in drinking water -- it's the physical matter, bacteria, and cysts that are the main concern.
DRM 'manages access' in the same way that a prison 'manages freedom'
If it filters everything down to a virus exactly what is left for the UV to kill?
This wouldn't filter out toxins like hydrocarbons and other nasty stuff that is in flood waters.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
From the Life Saver's site:
As the cartridge approaches the end of its life the bottle requires a greater number of pumps to induce water to flow. When the bottle requires a significant number of pumps to induce water to flow this indicates that it is nearing the end of its life. When no more water can be induced to flow despite continuous pumping, the cartridge has expired and it is time to replace it.
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.
Simple, portable, anti-viral filters are not new. The First Need Deluxe Water Filter/Purifier is $93 at Amazon. First Need is one filter that claims to meet EPA virus-removal standards by filtration alone -- a nice change from the yucky taste (and for some, the health risks) of iodine. Most antiviral filters involve an iodine element; when its job is done, a carbon element rids your water of any face-scrunching aftertaste. How To Buy a Water Filter
I have RTFA and I feel the same way you do.
The filter I use sells for less than $100 and it fits inside a Camelbak water bladder. If I'm particularly paranoid I can toss in an iodine tablet and add another $1 to the cost of purifying a gallon.
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
Another method of killing bacteria in drinking water is to expose it to excessive ultraviolet light. You can do this by putting it in clear plastic bottles, then set the bottles on a mirror in the sun. A reflective tin roof will also work. After an hour or so, this method kills 98% of harmful bacteria. Bacteria has a tolerance of normal amounts of UV light, but the mirror doubles the exposure, which they are unable to survive.
I don't know if fecal matter in water would be cleaned by this method.
Water purification methods.
Seth
$5 / month hosted VPS on linux = awesome!
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
Yup, they were called stilsuits in the dune universe.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
Mod this guy down, just another one of the "This already exists" posts that occur on every thread. Try reading the article before posting... 1) This filter's out virus' as well as bacteria, all of those outdoorsman's filters only filter bacteria. Huge difference there. 2) How quickly it does clog up, only takes 4k-6k liters before you have to change the filter...
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.
$385 is a high price but not really out of line considering the expected lifetime of 4000 litres (about 1000 US Gallons). But somehow thinking this is a new product or technology is stupid. There are lots of products out there that already do this.
.2 microns)
http://www.rei.com/product/662937?storeId=8000&catalogId=40000008000 (Filters about the same amount of water and can filter it faster for dispensing to multiple people, but costs a bit more)
http://www.sportsimportsltd.com/exxrwabopu.html (has to be replaced much quicker, but is convenient and it only costs $50 and would provide someone at least 30 days worth of clean water.)
And yes, Both of these filters can handle viruses down to 25 nanometers and lower (they are rated for 20nanometers or
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.
Disclaimer: I don't have the book with me, so I am going from memory.
I believe the evaporation occured in the first layer of the suit, allowing for the cooling effect. The cooling is from the phase change from liquid to gas and not from losing "warm moist air". (That's why sweating can cool you even in environments above body temperature.) The vapor was then captured in the second layer of the suit for processing and collection.
Reading code is like reading the dictionary - you have to read half of it before you can go back and understand it.
There is no such country, and there never was. That the pastoral stories you read never mentioned water-born parasites and illnesses (except for the one Slavic fable, where a boy turns into a goat after drinking from a puddle agaisnt his older sister's cautioning), does not mean it never happened.
It is not so much due to the much maligned modern pollution, it is due to the many organisms, whose existence predates man's. Stomach worms are just one — and fairly benign — example.
And if must drink such unfiltered and unboiled water, don't drink from a lake or other standing water. Try to find the fastest running stream you can — you'll have a better chance...
In Soviet Washington the swamp drains you.
It may sound funny, but it's actually a really valid, and incredibly easy way to make a solar still.
You place stones in a container to weigh it down, place that in a larger container filled with water, and cover it in plastic. A stone placed on top of the plastic sheet, directly over the inner container, allows the condensate that forms on the plastic to run down and drip into the inner container. Simple, effective way to get water that is safe to drink.
Saying you need a few containers is complicating things though. I have built and tested the idea using aluminum foil, plastic wrap, twigs (for support), and some river rocks. It worked perfectly - and I carry enough foil and plastic wrap in my wallet to produce it any time I need to. You may not get a lot of water out of it - and it's generally better to build a fire and use the foil to boil water to sterilize it, but if that isn't available it's great. Folded up, it takes up about as much space as 2-3 credit cards, well worth the space in my wallet if you ask me.
"In this house, we obey the laws of thermodynamics!"
and condensation heats the air back up. You still have to get rid of the waste heat, somehow. Merely transfering it from the inner part of the suit to the outer is insufficient.
It has been statistically shown that helmets increase the risk of head injury.
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.
Through a mechanism known as "this book is a work of fiction". Another option would be active cooling with fans and cooling ribs. I'm sure you could think of other options too.
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.
You know that show is fake, right?
Then the winter came, and the Grasshopper died. And the Octopus ate all his acorns. Also, he got a racecar.
Mass nouns can be pluralized to indicate multiple types of mass. For instance, "I ate lots of meat" and "I ate several lunch meats."
Ceci n'est pas une signature.
For one thing, condoms definitely make the collection of urine easier, for obvious reasons. They are also thinner and have a wider opening, which makes it easier to collect water from a river (larger opening and less resistance to filling up and stretching to max capacity). Not only that, they come in a protective foil package which helps resist punctures while being stored, and they're sterile.
Yep. Nothing more likely to get you sick from untreated water than bad 'ol giardia.
For me, I'm quite happy to stick with my combination of a katadyn siphon and a carbon filter. I don't even have to pump; all I need is something to hang the water bag from. One filter is good for about 10,000 liters if you use it properly, and it'll get everything down to 100nm; only $40. If I'm really worried about the water, I can throw in some flocculant, which will also help remove heavy metals.
If I wanted "instant" water purification like this product is for, I'd just get a survival straw. The problem with reverse osmosis systems is the pressure you need; it's far higher than with larger pore size filters. Imperfections in them can not only let viruses through, but even bacteria. It just doesn't seem worth it to me.
Then the winter came, and the Grasshopper died. And the Octopus ate all his acorns. Also, he got a racecar.
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.
and condensation heats the air back up. You still have to get rid of the waste heat, somehow. Merely transfering it from the inner part of the suit to the outer is insufficient.
I think it could be possible. If you have a thin sheet of highly reflective material between the inner and outer layers, this will help to reflect the thermal radiation outward instead of inward.
Also, why were the suits black? Probably the same reason that Bedouins wear black or other dark colors instead of white. It helps to set up convection within the garment that actually cools the wearer down better than if you were wearing white. And the black also radiates better -- although it also absorbs sunlight better.
You laugh, but the general advice for if you get lost *is* to stop moving. If a deck of cards will help with that, then by all means! The natural instinct when lost is to panic and run off -- doesn't matter which way. This is the worst thing you can do. Some people even ditch their packs to try and save time, thus losing the gear that they needed to keep themselves alive.
The simple facts are that if you're lost and you don't move about, rescue has a very good chance of finding you. If you do move about, rescue has very little chance of finding you. You move much faster than search and rescue teams, and the more you move, the further from where they'll start looking for you you'll likely end up. Stop, assess your situation, meet your needs (most importantly, water and shelter), and signal for rescue. With just water and whatever shelter the terrain requires, you can live for a month without even any food. Being lost doesn't kill you. Doing something stupid while lost does.
Only head off if you *know* that the given direction will bring you to civilization (i.e., if you're not really lost).
Then the winter came, and the Grasshopper died. And the Octopus ate all his acorns. Also, he got a racecar.