survival water filter straw

Hi All,

First off, thanks for all the great information. I have spent the last few weeks reading post and articles on this web site. Very enlightening.

This straw looks interesting:
http://giardiaclub.com/survival-water-filter-straw/index.php

Any comments?

Somehow, I think Doug said it best:

Avoid, also, straw style filters through which you literally suck the water. Though the concept is appealing, especially for weight conscious survival use, they don't filter very well in the first place and clog very quickly and are then useless. In fact, the EPA forced them off the market a while back, but you still see them around, or you may even have one, in which case, you ought to ditch it.

Also, in response to something on that site:

So, you become the "star" of the trip because you can remove giardia lamblia cysts from your water? Why? Does no one else on your trip have a water purification system? If so, you need better friends and colleagues to go backpacking with. Add to the irony all of the stuff you'll catch since you're all sucking on the same straw, but at least the giardia lamblia cysts are filtered! <img src="/images/graemlins/tongue.gif" alt="" />

Kharrell,

Welcome to the fire. I've seen those survival straws and have always been tempted. However, if Doug Ritter says stay away from something then it must be bad. He is the guru of gear.

-Blast

"...It will also make you the star of the backpacking trip with friends and colleagues..."

I suspect that really refers to the difficulty in sucking water thru one of those things. If you can do that, you could probably suck a golf ball thru a garden hose. Old joke, I hope you get the point...

I am going to partially disagree with Doug on this one. For the following reason.
There seems to be some question as to the effacy of chemical purification with regards to hard shelled parasites. It would seem to me that even MP1 tablets may not be 100% effective under certain conditions. Those conditions arise when the water is too cold or has high levels of turbidity. They can only be removed by physical filtration or destroyed by boiling. Sometimes boiling is impractical, or the contact time for maximum effect becomes excessive. Most effective filters are impractical for small survival kit's by virtue of their size. Under those circumstances there is a place for a filtration straw.
The best way to use is: Fill water bottle, Puri-Tab it. Leave for as long as possible. When you need to drink, insert the straw into the waterbotttle and suck up the water.

I keep a straw in my BOB as a backup to other more reliable methods. It is small enough to be a practical backup, where doubling up on a real filter system is less desirable.

BTW, it is really interesting how the people in Brisbane are resisting the notion of consuming purified recycled water. What do they think a Desal plant is? They are now below 20% in their reservoirs, and I shudder to think what the water quality of what's left is. Still, some of them would rather pay $10 a liter for water of inferior quality than to put recycle back in the dams. What a bunch of maroons.

Also see Do water filters really work?.

IMHO boiling is the only sure fire way.

That essay flirts with the critical point of gear maintance, service life and proper usage. Unfortunately, it then walked right on past.

A roughly treated or improperly flushed filter will fail, and like all mechanical systems they wear out. Keeping track of these things is the user's issue, not an issue with the equipment. Don't blame the gear if the user kills themselves accidentally.

They way a filter works is very simple. You have a pore of size X through a material . You suck up a contaminant of size Y. If Y > X, it doesn't stay in the water. Add in activated charcoal or certain epoxy resins, and they absorb certain compounds, trapping them perminantly (OK, you can get it out, but not in the field, and not without doing some really fun chem lab type stuff).

Not much can make it through a 1 micron filter with activated charcoal, that's smaller than protozoa, cysts, spores and cells, and most viruses. So it is something you can carry that is light weight, doesn't require fire or anything other than a catch container, and leaves no signature of it's use. The problem with the sippy-straw filters is that AFAIK, no one has made on with a 1 micron filter.

Boiling is good for MOST but not all biologicals. There are some, that while rare in the wild could be potential biowar agents- a concern if you are thinking in that direction. A filter will pick the spores out. That is a more pressing concern if you are allergic to certain pollens and mold spores, which boiling doesn't always deactivate as the reaction is to a protein.

It will also get a lot of pollutants, most of which are unaffected by 100*C. What the filter doesn't grab, charcoal will, which can't be as easily done with boiling. And I hate to say it, I don't care how far back in the boonies you are, you've got pollution potential. Such as an oil bottle that got lost or was improperly tossed from a logger, or arsenic from an old mine tailing, or any number of things that you really shouldn't drink.

Don't get me wrong. Boiling is good. A 1 micron filter is just better.

Thanks! That is what I wanted to know. I use a MSR waterworks to fill up 100 oz water pack. I leave the filter at camp. Trying to decide on backup water option in case the fiter fails or I don't make it back to camp. Boiling is my current plan.

Skip the desalination plant, what do they think rain is? Every drop of water on this planet has been through something's kidneys at some point. People deal or die.

"Fire" get it? Boiling? That's funny.