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28

Assuming you don't have a genitourinary tract infection, fresh urine should be sterile, the problem is that it is a waste product which, apart from making it not taste very nice, means that consuming it will increase the concentration of waste in your body which will require an increased volume of water to absorb and subsequently excrete, resulting in you ...


26

The EPA recommends boiling for one minute for most people, and three minutes for anyone above one mile in elevation. reference - http://water.epa.gov/drink/emerprep/emergencydisinfection.cfm#method That is what I have always done when backpacking. I don't boil for 10-20 minutes because it will kill my fuel supply and waste too much of the water. If I were ...


24

When you're asking for the safest way to purify water, you're asking for the method that removes the most harmful stuff from the water, like bacteria, viruses and larger impurities like mud or sand. No one method is really perfect at removing everything, so I usually use a two-stage approach: Filter: If the water source is cloudy, your first step should ...


23

Boiling- 185° water will become sterile in minutes. Bringing the water up to boiling point will typically sterilize it. At high altitude you may need to boil for a minute. Chemical- Iodine, chlorine, and other chemicals can sterilize water. Follow directions on products specifically designed for this purpose. Typically you'll need to mix it and then let ...


22

Copy and paste from the answer here: http://skeptics.stackexchange.com/questions/1540/is-it-a-good-idea-to-drink-your-own-urine-in-a-survival-situation Summary: You can do it, as a last resort, but it's dicey. The US Army doesn't think it's a good idea and lists it on its "Do NOT drink" list, stating in its Field Manual that it "contains harmful body ...


21

This article (*) gives a good summary of the efficiency of boiling as a method for making water safe for consumption. In particular, Table 2 provides a summary of the temperature and time required to kill various micro-organisms. A distinction should be drawn between killing all pathogens and making water safe to drink. Sterilisation of water (killing all ...


18

Via WebMD Large amounts or long-term use of iodine are possibly unsafe. Adults should avoid prolonged use of doses higher than 1100 mcg per day (the upper tolerable limit, UL) without proper medical supervision. However I seriously question that 1100 mcg number because people in Northern Japan have been found to consume over 80,000 mcg per day due to a ...


18

Urine is normally sterile (barring urinary tract infections) - so, from bacteriological stance, fresh urine isn't going to hurt. The problem is - urine is a waste product, and so is full of stuff that your body wants to be rid of. Worse, as you get more dehydrated, your body produces more concentrated urine. That said - as a short term measure to keep ...


17

I would get a ceramic filter that is rated to remove metals like arsenic (this is a particular issue in the UK where most surface water in the wild country can harbour arsenic - but I'd rather assume all ground water to be 'tainted' than drink it and become poisoned). I've used some hand-pumped filters which can draw water from a lake or river, and filter at ...


12

In the core alps (Liechtenstein, Switzerland, and Austria), you can drink water almost everywhere directly without filtering. There are only two exceptions: If there is a thing or something like this that forbids drinking it, or if you can see an obvious reason not to drink it, like for example a strange smell or abnormal color. In the other countries in ...


12

There is typically no need to purify water collected from natural sources in the wilderness. For example, in a survey of 69 sites in the Sierra, every site had concentrations of Giardia cysts much too low to make anyone sick.[Rockwell 2002] The perception that backcountry water is unsafe to drink without treatment is folk wisdom that is controverted by the ...


12

You need to distill it - I'm assuming that freezing is not an option (unless you're camping in the extreme latitudes). This is easiest, as the ice on top is almost pure water. Where you don't have a freezer available - boiling the water, capturing the steam and condensing it back to water will provide pure water.


11

Boiling kills everything -- giardia, cryptosporidium, other bacteria, and viruses. 185F (140.6C) for a few minutes will do it, and boiling for one minute will do it. (Boiling is lots of big bubbles, not just a few small bubbles on the side of the pot.) Some people recommend longer boiling times at higher altitudes because water boils at cooler temperatures ...


10

The key is to always have a trash bag. Your most reliable backwoods method for clean water is condensation, either through natural action, or via a still of some kind. The primary component of this is having large enough suitable material to make said still. If you are depending on natural action, then surface area is still key. Assuming you left your ...


10

Filter the water right away, when filling the bottle. This way I'm sure the water inside the bottle is safe for drinking. This. Why? The main point for me is accessibility of that water. If you come to a situation where you need fresh water, then it may not just be because you've set up camp, you've got a while to spare and you feel like a drink. It ...


9

This article (*) gives a good summary of the efficiency of boiling as a method for making water safe for consumption. In particular, Table 2 provides a summary of the temperature and time required to kill various micro-organisms. Sterilisation of water (killing all living containments) is not necessary to make water safe to drink. For example, boiling may ...


9

Boiling eliminates only a certain class of contaminants that can make you ill. Specifically living bacteria and other microorganisms (protozoa, amoeba). It does not purify, or decontaminate the water completely. Certain bacterial and algal toxins can survive boiling and make you sick, and as Russell pointed out, there are also inorganic contaminants that ...


8

THE official information can be found on the CDC webpage. The CDC defines the problem in terms of what you're trying to kill: Protozoa, Bacteria, or Viruses. They address each of those in terms of water treatment methods: Boiling, Filtering, Chemical Disinfection, (or now-a-days UV Treatment). Please read what they have to say before you head into the ...


8

Outdoors you can dig a hole and build SOLAR STILL. It is quick and dirty but works very well and it is time tested. Or you can put big plastic bag over brach with a lot of leaves on it and put rock on the bottom to capture the water. Make sure you don't do it on foliage that is toxic to people. If you have the bucks you could get a portable Reverse ...


8

Once you open it up to toxins, the answer is clearly no, boiling is not enough. There are many examples: Alkali Salt Heavy Metals Blue-green algal toxins, which appear to be present in your photo If you are trying to clear up truly noxious water, try this method: http://outdoors.stackexchange.com/a/351/127


8

nope yep (actually, yellow, not purple, thanks Clare) Not in my experience, but I use clarifiers which remove the flavor in the water. Also to clarify from comments, we did this for years before we started carrying a filter and it never damaged our containers. The plastic probably gets more damage from the sunlight caught during hiking than from the ...


7

Well it's been banned for sale in Europe for use in purifying water. (http://www.grough.co.uk/magazine/2009/08/13/eu-ban-will-end-walkers-use-of-iodine) As that webpage mentions Chlorine is an alternative, but leaves a nasty taste (although I believe you can add another chemical to neutralise the taste) Alternatives are a water filter, or UV light ...


7

Botulinum toxin is particularly tough, as is Bacillus cereus. B. cereus is more likely found while camping. For a good reference see: http://aggie-horticulture.tamu.edu/extension/poison.html But your goal is not so much to kill everything as reduce the level to the point where it does no harm. The dust you breathe, the things you touch, and (yick!) the ...


7

Boiling is the best thing to do, as stated already - I was always taught to boil for 2 minutes and then it's safe. (Far from an accepted time though. For debate on how long you should boil, see here: How long does water need to be boiled for to kill all bacteria / viruses?) As pointed out below though it may be wise to use a filter to get rid of any toxic ...


7

As I understand the technology, your microfilters will not expire on the shelf if maintained and stored properly. Their lifetime is determined by the number of gallons pumped. What can happen is if you don't properly dry out your filter before storing then it will develop mold. In that situation you can decide if it is best to clean the filter or replace ...


6

My understanding is that anything above 4000 metres you can drink due to there being a low chance that anything living will affect the water i.e. animal faeces and bacteria etc.


6

If safety is your primary concern, then the only two methods can guarantee safety from major contaminants (microbial or otherwise) these are Distillation and Reverse Osmosis Distillation Boiling alone will leave most contaminants in the water, such as heavy metals, hydrocarbons, etc... multi-stage distillation will both kill pathogens and leave most ...


6

If I am using a water-pump filter. Is it necessary to combine this with a water purification tablet? As discussed in this answer and at greater length here, the need to treat backcountry water before drinking it is largely a myth. Neither the filter nor the tablets are needed. You're better off focusing your efforts on avoiding the real reason that ...


6

The bottom line is there is always SOME risk. Whether to take that risk or not is your choice. Fast running + isolated + high elevation = prettttty low risk. With that said the biggest concern is, unless you are drinking right from the source, you have no idea what has happened upstream from you. There could be a dead animal snagged in the stream, animal ...


5

I've used the Platypus GravityWorks filter with great success and found it to be reliable, easy to clean and it filtered water quicker than any hand-pump filter I've ever used. What I really liked about this filter was that not only was it relatively small and light compared to other filters, but there are no moving parts whatsoever. If you were to need to ...



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