Catching up on some of my back reading and found this article that I thought might be interesting to some here.

http://www.jfponline.com/Pages.asp?AID=5823&issue=January2008


The links in the article seem broken, here is a link to the Army document.
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA449339&Location=U2&doc=GetTRDoc.pdf

Wow, the SteriPEN didn't do very well at all. It's time for me to re-evaluate its place in my pack even as a secondary purification device.

Unless weight or space are major issues, I think the best way to go is a Katadyn pocket, with some MP-1 tablets(chlorine dioxide) as a backup(not so much in case the filter breaks, which is extremely unlikely to ever happen, but it's good to have backup anyway since the tablets weigh almost nothing, and you may be injured or otherwise unable to operate the pump).

This filter is one of the most expensive, heavy, and relatively slow, but it is by far the most durable, simple, and easy to clean and maintain in the field. It will easily last a lifetime, or several, as long as you don't lose it. Plus no batteries or chemicals to replace or expire(though after many years you may need to replace the O-rings).

i have no problem sticking to my SterPen and micropur tablets as my two options. the only disasvantage to the sterpen in the study was can't be used in turpid waters.

I'm a recent convert to the Katadyn Pocket too, its rock solid in every way that the Hiker Pro is not, and the Hiker Pro is a fairly reliable filter, but the plastic off-set handle has always niggled at the back of my mind - what if it breaks? Boy Scouts love the Pocket too, no shortage of volunteers to pump water - it pumps water inline and the consensus is its much the easier to use.

+1 with comms comment, I'll stick with my Steripen as well with 30 tab micropur tablets as backup. You just have to make sure the water is relatively clear, I haven't got sick with one yet and I carry a katadyn Combi for a prefilter for really really bad dirty water in case, but I rarely need it for where I go, the steripen is usually all I need. The steripen is awesome for me with the capability of running it 100% with no batteries off of solar cells in a emergency. UV filtering has been around for quite awhile, used for purifying water as well as air and instruments, it's a proven technology with it's disadvantages are murky water, relying on electronics and the lamp will need changed years down the road. I wonder if the micropur tablets in time may have to be replaced if not used in a long time (like a shelf life), I'm not sure though, I know Iodine lasted for years but doesn't kill the good stuff. Anyway you wont have the 4 hour dwell time with the steripen and that can mean life or death in some cases, both have their advantages and disadvantages, that's why I carry both.

[quote=falcon5000 I wonder if the micropur tablets in time may have to be replaced if not used in a long time (like a shelf life), I'm not sure though, I know Iodine lasted for years but doesn't kill the good stuff. [/quote]

Here's an email I got from Katadyn when I had the same question a few months ago.... The tablets I own have a 2012 expiration date...

" The tablets may last longer however since the product hasn't been around for say 6 years the company would not have the data in order to test.

Regards,

***** ******/ Customer Service
Katadyn North America
6325 Sandburg Rd Suite 400
Minneapolis, MN 55427
Phone- 800-755-6701 or 763-746-3506
Fax- 763-746-3540 "

Perhaps the setup it just to expensive, complicated and not robust enough for the US Army. Doesn't mean to say it doesn't work and the ability to quickly purify water (4hrs is a very long time for chemical purification if your thirsty by which time you could have made a fire*, boiled the water and made a brew, drunk it and done the washing up) with a lifetime capacity of nearly 2000 gallons of water would probably be more than the US army requirement for a water purification system. Oh and no chemical aftertaste like drinking from the local swimming pool.

* I don't think the US Army generally issues any means to get a fire going either to allow the ability boil some water in a mess tin or metal pot and make a brew up, having to rely on chemical heaters, which are pretty restrictive. How on earth you would expect a GI to make a decent cup of Earl Grey with a chemical heater is really beyond me I'm afraid.

Thanks DannyL about the shelf life info and Am_Fear_Liath_Mor's got the set up, the only difference for me is I upped the solar panel to a 40 watt but man that steripen is great for quick purification with no shelf life, just plug and go

Actually, MREs still contain paper, damp resistant matches (against humidity, not submersion). And you're still issued the canteen cup and canteens (canteens have an NBC mask adapter hydration systems don't). If, theoretically, you were actually carrying your canteens and the cup, everytime you get lunch you get the means for lighting a fire and having a brew up. I think the main reason we don't is operational security and logistical support. If you're out traveling light, you don't want flame and smoke giving you away. If you're not, someone generally comes around and feeds you and brings insulated containers of coffee and what have you. Or you eat in a giant FOB dining facility.

Oh, and so many people smoke in the army, if you can't find a lighter to get a fire going, you should be more worried your smokers twigging out from lack of nicotine.