#262660 - 08/21/13 03:25 AM
Water disinfection methods
|
Sheriff
Carpal Tunnel
Registered: 12/03/09
Posts: 3840
Loc: USA
|
Updates to the list in this color.Costco had a Steripen for a nice price so I picked one up. It led me to think about disinfection methods. - Iodine tabs, like Potable Aqua. They make water taste nasty unless you have the neutralizer or drink mix to put in it, and reportedly don't work against Giardia
- Chlorine dioxide tabs, also like Potable Aqua. I think they're a bit easier to use, they don't make water taste nasty, and they work against Giardia.
- Calcium hypochlorite, such as pool shock. Best used when treating a large volume of water, I would think. Requires more steps than the other methods, but can also be used to create a bleach disinfection solution for other purposes.
- Boiling. If you have a container, fuel and a way to make fire, can't be beat.
- SODIS. Easy if you have the container, sunlight and time.
- Steripen. Quick and easy...if you have batteries.
- Filters. Quick and relatively easy, but may not remove viruses.
- Iodine crystals. Roughly the same as iodine tabs? Need more information.
- Miox. Uses both batteries and salt, not sure if there's an advantage to this.
- Bio-sand filter. A great option for long-term use in a single location, not very portable.
- Household bleach. Like the calcium hypochlorite but easier to use and doesn't store as long.
My field experience is limited -- I've boiled water while camping but normally I bring water so as not to have to treat it. Have I missed any methods that I should consider? What have been your experiences?
Edited by chaosmagnet (08/23/13 09:09 PM)
|
Top
|
|
|
|
#262666 - 08/21/13 03:57 AM
Re: Water disinfection methods
[Re: chaosmagnet]
|
Geezer in Chief
Geezer
Registered: 08/26/06
Posts: 7705
Loc: southern Cal
|
Boiling is definitely my preferred method. It has always worked for me, in some cases with some pretty nasty water sources. I am not so sure that water literally has to reach the boiling point to kill bugs; after all, milk is pasteurized by heating to 165F which is the same temperature to which safely cooked meat should reach. Years ago, I routinely drank untreated water from mountain springs, but I am a bit more cautious now.
_________________________
Geezer in Chief
|
Top
|
|
|
|
#262672 - 08/21/13 09:49 AM
Re: Water disinfection methods
[Re: chaosmagnet]
|
Addict
Registered: 09/16/04
Posts: 577
|
Primarily I prefer to boil but my go to emergency method when that is not an option is chlorine dioxide tablets. It will kill viral, bacterial and cyst based threats. I do have a water filter straw but that alone won't eliminate all threats (viruses are too small and will get through). Its primary advantage is allowing me to drink water treated with chlorine dioxide in 15-20 min (after bacteria ane viruses have been killed) instead of having to wait 4 hours for it to kill the cysts too, and for taste. Which is why I don't invest in the super expensive pump type filters. Hell a Millbank bag would work if you are just trying to keep the chunks out.
It seems to me steripen is a decent setup but it doesnt fill a niche for me at the moment. I would imagine because it depends on exposure to UV light that water would have to be pretty clear for it to be effective and might need to be used in conjunction with basoc filtration (even handkerchief) for best results.
Miox makes a water purification setup that uses batteries and salt to make an ionized solution that is supposed to work well and IIRC you can tweak it to purify different amounts..
|
Top
|
|
|
|
#262674 - 08/21/13 01:23 PM
Re: Water disinfection methods
[Re: chaosmagnet]
|
Pooh-Bah
Registered: 07/11/10
Posts: 1680
Loc: New Port Richey, Fla
|
I don't spend time in the outdoors like most of you do, but I do carry a half dozen chlorine dioxide tabs and a water transport bag in my wallet... my major concern is "boil order" for water main burst or contamination with a sewer line... so I opted for the .1 micron Sawyer 5 gal bucket for home... backed up with calcium hypochlorite/Clorox... just a lot more convenient for an old guy
|
Top
|
|
|
|
#262679 - 08/21/13 03:17 PM
Re: Water disinfection methods
[Re: chaosmagnet]
|
Enthusiast
Registered: 08/03/12
Posts: 264
Loc: Missouri
|
I would not clain expertise in this subject, but my understanding is filters will remove larger nasties such as bacteria, amoebas and cysts; but will let viruses pass through. If your in a region where the viral load of streams is high, you need more than a filter. Either a purifier or chemical treatment is indicated. If the viral load is low, a filter is sufficient. Mechanical filters and purifiers both have the problem of clogging, but prefilters help. When i have camped, I have usually been happy with a filter.
|
Top
|
|
|
|
#262683 - 08/21/13 04:08 PM
Re: Water disinfection methods
[Re: chaosmagnet]
|
Addict
Registered: 12/06/07
Posts: 418
Loc: St. Petersburg, Florida
|
Chaosmagnet,
I have the lot of tools for water prep (Steripen, Miox, Katadyn Filter, Tea Kettle, tabs, etc.) and they are all great in certain circumstances. For most uses though the new Sawyer Purifyer filters which will remove virus will do it all. I will still use the others where their strengths fit, but the Sawyer will do most of them almost as well and in many cases better.
Since virus populations are low in most of the North American Wilderness, a filter (I have used a Katadyn Pocket for over 30 years) has been my go to for normal use. Before that, in the high rockies I did not use anything. It also has worked well when traveling, but newer tools have displaced it there.
The Steripen is now my normal traveling (out of the country) source, Works well in a hotel room or by a lake or stream. Kills everything but works best in clearish water. Also great for canoeing. Biggest limitation is the amount of water you can produce at one time. Not good for group camping or in the desert where you may have to fill several gallons at one time. In the canoe you can quickly produce a bottle full any time you need it. Often used with Miox (or now the Sawyer) for working from canoes or small boats.
Miox (produces chlorine dioxide) is great for producing large quantities of water at one time but is slow for anything (15 min to several hours depending on potential problems). It is slowest for large cysts which are common in North American Waters. In third world countries I have been known to filter then use Miox for virus (the shorter time frames. This is a common recommendation from the Wilderness Medical Society (to use two methods). When working from a base camp in canoes, I set up a bag or two(10L) at the camp, fill it in the morning and have safe water when I return for dinner and cleanup. After dinner I fill the bags again and have water for the morning. I use the Steripen during the day since water is all around. The Sawyer bag to bag purifier may replace this, but not necessarily.
Tabs I have used in the past, still use after filtration in places where virus are a problem and I carry them in emergency kits because they are small. Taste and quantity of water are problems so although I usually carry some, I don't actually use them much any more.
The Sawyer I have is a gravity filter and requires 2 bags, dirty and clean. It works best as a replacement for the Miox and MSR bladders. It needs to set for a while.
I understand Sawyer is going to bring out a portable version of there filter (it may be out) which will be great for other uses as well. Just look carefully, some Sawyers are filters and some are Purfyiers.
Respectfully,
Jerry
Edited by JerryFountain (08/21/13 04:09 PM)
|
Top
|
|
|
|
#262685 - 08/21/13 05:41 PM
Re: Water disinfection methods
[Re: chaosmagnet]
|
Old Hand
Registered: 03/19/05
Posts: 1185
Loc: Channeled Scablands
|
Bio-Sand Filter-Long Term, Household http://www.cawst.org/en/resources/biosand-filter"The biosand filter has been studied in the field and in labs. It has been shown to remove the following from contaminated water: Up to 100% of helminths (worms) Up to 100% of protozoa Up to 98.5% of bacteria 70-99% of viruses The filter can also remove up to 95% of turbidity (dirt and cloudiness), and up to 95% or iron (which people often don’t like because it turns water, laundry and food red!). Like other filters, the biosand filter cannot remove dissolved contaminants or chemicals, such as salt, arsenic or fluoride. There is an adaptation of the biosand filter using rusty nails, called the Kanchan Filter, which can remove arsenic from water."
|
Top
|
|
|
|
|
|
|
|
|
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
18
|
19
|
20
|
21
|
22
|
23
|
24
|
25
|
26
|
27
|
28
|
29
|
30
|
|
0 registered (),
444
Guests and
26
Spiders online. |
Key:
Admin,
Global Mod,
Mod
|
|
|