Anyone ever use a steripen? If water were to be filtered through a sgrainer, cloth, and then a steripen used on it; it should be safe to drink, right?

You'd want to make absolutely certain there are no particulates outside of minerals after filtering, many protozoa like Giardia can attach themselves within tiny solids only to hatch later.

In an emergency, this is a quick and effective solution for the desperate, though I'd still boil the water first if possible, but then, if you could, you wouldn't need a Steripen.

Ya know, this would be perfect in places like Mexico, where the water looks fine, but is infested with scochi chingos.

Quote from: Solar on August 31, 2014, 10:25:27 AM
You'd want to make absolutely certain there are no particulates outside of minerals after filtering, many protozoa like Giardia can attach themselves within tiny solids only to hatch later.

In an emergency, this is a quick and effective solution for the desperate, though I'd still boil the water first if possible, but then, if you could, you wouldn't need a Steripen.

Ya know, this would be perfect in places like Mexico, where the water looks fine, but is infested with scochi chingos.

Yeah, I'm thinking this would be a last resort type thing. I'm just thinking if starting a fire and boiling isn't practical because you're trying not to have the smoke of the fire give away your location, this might be an okay solution. I'm sure it would taste horrible though.

Have you ever used a Steripen?

I have a couple of Steripens and they do seem to work. However, they are fragile and are better as a back-up then as a primary system. Make sure all water is as strained as is possible, without debris to harbor nastys. The water will taste like whatever it is, and if you use a flavor additive, it will taste like flavored crud. be  careful to wipe all of the drips off of the container so you don't contaminate the treated water.

This has been bugging me about UV light killing Giardia. Sure, it'll kill active ones, but what about the cysts?
From all my study on this little bug back in the early 80s when I got it and suffered for two months with what seemed like the worst flu in the world.

What I found out was these cysts attach themselves to your stomach lining, where they absorb the nutrients before your body gets a chance at it.
After 30 minutes they detach and split in two, where they reattach once again, and the process continues if unabated.
And usually if infected, you can easily ingest a million of these cysts in one swallow.

My issue with UV light is it can't penetrate the shell of the cyst, in fact little can, except for chemicals such as iodine, Bromine and chlorine etc, standard water treatment chemicals.

I'll do some research and see what I can find, but I'm highly skeptical of such a low wattage output of UV light having the ability to kill cysts, unless you leave it on for more than the 30 min life cycle of Giardia.
Which brings us to the rolling boil method for a full minute to thoroughly kill all cysts and bacteria would be safer and more effective.

I'll see what I can find on this.

I did find this from the CDC, which might be helpful.
Giardia is between 8 and 12 microns in size.

A Guide to Water Filters
Filtering tap water: Many but not all available home water filters remove Cryptosporidium. Some filter designs are more suitable for removal of Cryptosporidium than others. Filters that have the words "reverse osmosis" on the label protect against Cryptosporidium. Some other types of filters that function by micro-straining also work. Look for a filter that has a pore size of 1 micron or less. This will remove microbes 1 micron or greater in diameter (Cryptosporidium, Giardia).

There are two types of these filters — "absolute 1 micron" filters and "nominal 1 micron" filters but not all filters that are supposed to remove objects 1 micron or larger from water are the same. The absolute 1 micron filter will more consistently remove Cryptosporidium than a nominal filter. Some nominal 1 micron filters will allow 20% to 30% of 1 micron particles (like Cryptosporidium) to pass through.

NSF-International (NSF) does independent testing of filters to determine if they remove Cryptosporidium. To find out if a particular filter is certified to remove Cryptosporidium, you can look for the NSF trademark plus the words "cyst reduction" or "cyst removal" on the product label information. You can also contact the NSF at 789 N. Dixboro Road, Ann Arbor, MI 48113 USA, toll free 800-673-8010 or 888-99-SAFER, fax 734-769-0109, email [email protected], or visit their Web site at www.nsf.org/certified/DWTU/External Web Site Icon. At their Web site, you can enter the model number of the unit you intend to buy to see if it is on their certified list, or you can look under the section entitled "Reduction claims for drinking water treatment units - Health Effects" and check the box in front of the words "Cyst Reduction." This will display a list of filters tested for their ability to remove Cryptosporidium.

Because NSF testing is expensive and voluntary, some filters that may work against Cryptosporidium have not been NSF-tested. If you chose to use a product not NSF-certified, select those technologies more likely to reduce Cryptosporidium, including filters with reverse osmosis and those that have an absolute pore size of 1 micron or smaller.

http://www.cdc.gov/parasites/crypto/gen_info/filters.html

I picked up a "Sawyer Mini Water Filtration System" and have been satisfied with it. It filters water fast enough for my needs, is simple to use, is compact, and supposedly is pretty effective in filtering out most problem causing bacteria. It cannot filter out viruses though, and won't filter out impurities such as chemicals and what not. I take it when I go on long hikes in case I run out of water.

Only down side with it is you can't let it freeze, otherwise the ceramic filter will bust. I've used it a bunch of times and haven't gotten sick yet, so I guess it works pretty decently. The reviews I've read have been pretty satisfactory as well. Best part about it is it's really cheap (~$20).

Watch out: UV Light & Giardia: UV light does not kill cysts, according to Dr. Amin. Websites that advertise use of UV light to kill giardia may be misleading. UV light will kill Giardia trophozoites but the real concern for drinking water is the Giardia cysts, since it is the cysts from stool that appear there. Other treatment methods may be needed if Giardia is present in the water supply.

UV light for water disinfection where Giardia is present has, however, been successfully used in combination with chlorination as an approach to killing Giardia in water.

http://inspectapedia.com/water/Drinking_Water_UV.htm#Giardia