Gunhub.com banner

1 - 6 of 6 Posts

·
Registered
Joined
·
356 Posts
Discussion Starter #1
You don't need to 'sterilize' water. Sterilization is the destruction of all microorganisms in, on and around an object. What is needed, is disinfection (killing of pathogenic, or disease causing, organisms).

Disinfection can be done many ways, including filtration, heat, ozonation, and chemical disinfection.

Despite many stories to the contrary, simply boiling water will disinfect it. At any elevation you're likely be at, the boiling point of water is high enough to kill (or denature) anything in the water. You don't need to boil it for any particular length of time, just get it boiling to a good rolling boil.

Filtration is a good method, you should use a filter that has an absolute rating of 0.2 micron diameter or LESS (0.1 micron). Personally, I use iodine crystals first, then filter the water.

Chemical disinfection is the use of various chemicals (usually a halide like chlorine or iodine) in the water. It's usually a quick, economical and effective method.

Here is a summary of water disinfection chemical usage based on the Wilderness Medical Society Practice Guidelines 2nd Edition, edited by William Forgey MD (page 63):

For chemical disinfection, the key is the concentration of halogenation:

Concentration of Halogen
Contact time @ 5oC / 41o F Contact time @ 15o C / 59o F Contact time @ 30o C / 86o F
2 ppm 240 minutes 180 minutes 60 minutes
4 ppm 180 min 60 min 45 min
8 ppm 60 min 30 min 15 min


Per liter of water, Iodine tabs (tetraglycine hydroperiodide, EDWGT (emergency drinking water germicidal tablets), current USGI water purification tablets, Potable Aqua (trade name), Globaline (trade name):
4 ppm – ½ tab 8 ppm – 1 tab

NOTE: These tablets should be gunmetal gray in color when used – if rust colored, they are useless: The free iodine has combined with atmospheric moisture. The bottles should be kept well sealed and replaced often. There's a danger in 'checking' to see if the tablets are good, it lets air into the bottle and then they can go bad.

For 2% iodine (tincture of Iodine)
4 ppm – 0.2 ml (5 gtts) 8 ppm – 0.4 ml (10 gtts)
(gtts=drops)

NOTE: Tincture of Iodine should NOT be used as a wound treatment, so this is not a good option for a 'dual use' item.

10% povidone-iodine (Betadine)
4 ppm - 0.35 ml (8 gtts) 8 ppm – 0.7ml (16 gtts)
NOTE: Solution only, NOT SCRUB - Scrub has soap in it and tastes bad, as well as having a pretty dramatic laxitive effect.

Saturated (in water) Iodine crystals
4 ppm – 13 ml 8 ppm – 26 ml
Polar Pure (tm)

Iodine crystals in alcohol
0.1 ml / 5 ppm 0.2 ml / 10 ppm

Halazone tablets
4 ppm – 2 tabs 8 ppm – 4 tabs
Monodichloroaminobenzoic acid

NOTE: The old Vietnam era chlorine tabs are decades out of date. Chlorine tabs decay even more rapidly than iodine tabs. Not recommended.

Household bleach (Chlorox)
4 ppm – 0.1 ml (2 gtts) 8 ppm – 0.2 ml (4 gtts)

Note: Bleach offers a relatively economical method of treating large (gallons) of water at a time. 4 liters is approximately 1 gallon.

For very cold water contact time should be increased.

If drinking this water after disinfection, flavoring agents (drink mixes, etc) can be added: This must be done AFTER the period allocated for disinfection (the disinfecting agent will bind to the organic material and not work).
 

·
Registered
Joined
·
127 Posts
Flighterdoc,

Thanks for a great post on this subject. I currently have a filter with a nominal .3 micron diameter. It is supposed to get out bacteria but leave viruses. I was thinking that I could use the filter to get most of the contaminants out and then be able to use a lower dose of chlorine to kill the few contaminants that are left. Is this correct, or would I still need the full dose of chlorine whether it was filtered or not?
 

·
Registered
Joined
·
356 Posts
Discussion Starter #3
horseshoe3 said:
Flighterdoc,

Thanks for a great post on this subject. I currently have a filter with a nominal .3 micron diameter. It is supposed to get out bacteria but leave viruses. I was thinking that I could use the filter to get most of the contaminants out and then be able to use a lower dose of chlorine to kill the few contaminants that are left. Is this correct, or would I still need the full dose of chlorine whether it was filtered or not?
I'd get a filter with less than .2 micron absolute filtering - nominal is 'who the heck knows whats really going on'.

And if you want to treat it (I usually do) treat it first, then filter it. It helps get the bad taste out.
 

·
Registered
Joined
·
356 Posts
Discussion Starter #5
Re: hi

bdcochran said:
How about ultraviolet pen technology?
I don't trust anything that requires a lot of different things to work correctly.

Chemicals are reliable.
 

·
Registered
Joined
·
125 Posts
I just happen to have bought a few months ago some:
Katadyn Exstream XR Water Purifier Bottle
Amazon.com had a nice sale on them.

My bro who is a retired NBC lifer told me this is what he got for his family.

It will filter radioactive water, and just about anything else. Filters good for 125 refills.

Damn I hated tho clorine tabs!
 
1 - 6 of 6 Posts
Top