
Russtang writes in with a super-cheap water purification straw… – “Just saw this at my local HarborFreight. Says it removes pathogens as small as 2 microns and treats up to 20 gallons. On sale for $8 – FRONTIER(TM) WATER PURIFICATION STRAW – Ideal for hiking, camping, travel in foreign countries, and emergency use. Removes pathogens as small as 2 microns, including Giardia, Cryptosporidium and E. Coli bacteria, Activated carbon filter removes chemicals and improves taste, Super compact, fits in a pocket, Treats up to 20 gallons of water.” – Link.
Previous:
MSR MIOX Water purifier – Link.
SteriPEN portable water purifier – Link.
Jon also reminded me about the life straw – Link.


Would you really want to put something you bought from Harbor Freight in your mouth?
OK, I’m hoping that 2 microns is a typo because pretty much every pathogen is smaller than that. Typically a 0.45 micron filter is needed to remove bacteria and a 0.22 micron filter for viruses.
No no two microns is correct. Note what it filters though “Giardia, Cryptosporidium and E. Coli bacteria”. E. Coli is about 2 microns so its caught, Giardia is about 10 micron, and Cryptosporidium is about 5 microns. These are arguably the 3 most common and WORST things you could pick up in the bush in North America. So what if alot of bacteria and viruses get through, as long as your not drinking from a festering swamp, or a lake in a 3rd world country you should be ok.
Also this is marketed as a “back up” method of water filtration.
E. coli are only about 1 micron across. Here’s a link to a lovely video of E. coli swimming through a 1.5 micron channel, just like they would up though the straw.
http://www.nsf.gov/news/news_videos.jsp?cntn_id=104283&media_id=55634&org=NSF
Harbor Freight got some decent stuff…
but aside from dishing HF, there are similar gadget/filter called LifeStraw that was designed for used in 3rd world. It only filtered to 15 micron, but used carbon and halogen-based resin to takeout the other small bugs. Mabe the HF modle have the same…U know how good we Chinese are at copying other ppl’s stuff…
their website: http://www.lifestraw.com/en/low/low.asp
Oh BTW, acoording to a engaget article…the LifeStraw costs ~$2.
http://www.engadget.com/2005/08/18/lifestraw-purifies-water-instantly-for-under-2-a-year/
I picked one up yesterday. One thing that I can’t find mentioned is that it weighs less than an ounce. Light enough to throw in your pack and forget about it. That is until you’re lost with no potable water to drink.
Russ
>Would you really want to put something you bought >from Harbor Freight in your mouth?
Interesting that you put that comment there. For a real emergency filter get the LCD in your group to drink the water then drink their urin. Let them act as the filter for you.
Or, just do what I do and staty in the civilized part of the world and drink nothing but soda.
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