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37 votes
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Ways to desalinate water when "lost at sea"?

Salt dissolves in water so will pass though a normal filter or cloth. You can try that with a coffee filter at home. So there's definitely an error in the article. A still (i.e. distillation ...
Chris H's user avatar
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37 votes

Ways to desalinate water when "lost at sea"?

You can place an empty cup in the middle of a lightly filled bucket of sea water. You then place a plastic bag over the bucket, with a stone in the middle so it has a dip in it over the cup. The sea ...
Robin's user avatar
  • 471
34 votes
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Can you boil/decontaminate water with heat from a magnifying glass?

Let's do some back-of-the-envelope calculations. The specific heat of water is the amount of energy needed to raise the temperature of a particular amount of water by 1 degree C. This is 4.186 joules/...
Greg Hewgill's user avatar
  • 1,543
19 votes
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Iodine tablet correct use and efficiency

Welcome back to good old chemistry class! Apologies if this gives you nightmares. First, the tablets used for water purification are not elemental iodine, but a crystal form called Tetraglycine ...
cobaltduck's user avatar
  • 5,178
18 votes

is water filter log reduction multiplicative?

No. Filters don't work like that, though there can be some benefit to double filtration as I'll explain below. I don't know the mathematics of it though. Basically what happens inside a filter is that ...
bob1's user avatar
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14 votes
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How do you boil water without a proper container?

A watertight container is what is required here. The best thing is metal but if we're without this you can use plastic bottles on the shoreline folded paper a hollowed out and charred piece of wood* ...
Chris J's user avatar
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13 votes
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How do I test my water filter?

General information Unfortunately the only real way to get your water filter checked is to send a water sample to a lab. You may only want to check whether water is still flowing through, but that's ...
OddDeer's user avatar
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13 votes
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Is pouring boiling water into a plastic Nalgene bad for you?

Most Nalgene bottles are designed to be able to stand up to boiling water. Today, many hikers and others recognize the distinctive appearance of Nalgene-branded bottles. Its laboratory pedigree is ...
Charlie Brumbaugh's user avatar
13 votes

Filtering fine silt/mud from water (not necessarily bacteria etc.)

While coffee filters would work great as suggested in a different answer I would probably just use something I was going to bring anyway like a handkerchief. That should work reasonably well, be ...
Erik's user avatar
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12 votes
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UK blanket bog peatland water - safe to drink?

EDITED TO ADD: Please also read the other answer by cbeleites unhappy with SX about the risk of heavy metal contamination. The information in my original answer (below) is still accurate regarding ...
csk's user avatar
  • 4,364
10 votes
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Can any automotive fluids be made safe to drink?

THIS IS A HIGHLY DANGEROUS IDEA AND SHOULD ONLY BE ATTEMPTED WHEN DESPARATE There are three fluids in your car that contain water: the battery electrolyte, the washer fluid, and the coolant. ...
Mark's user avatar
  • 2,998
10 votes

Is pouring boiling water into a plastic Nalgene bad for you?

Nalgene is owned by Fisher Scientific. They do lab bottles, recreational bottles, and lab equipment. Boiling water is a probable exposure. If bad thing happen the lawyers would be putting out ...
paparazzo's user avatar
  • 7,186
10 votes

Ways to desalinate water when "lost at sea"?

Disclaimer: This is not safe. This is not well tested. This belongs here, not on the other question. This is weak evidence in collaboration for the drinking seawater claim. On request by Seth ...
Joshua's user avatar
  • 613
10 votes
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Filtering fine silt/mud from water (not necessarily bacteria etc.)

Leaving aside your assertion that water in the high mountains is likely to be biologically safe. The answer depends on how big the particulates are. The smaller they are, the harder it is to find an ...
bob1's user avatar
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9 votes
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How can I desalinate ocean water enough for cleaning or showering?

The problem is that desalinating water is hard; nearly desalinating it isn't much easier (it would be possible to design a bad reverse osmosis system but there isn't much market for that). Instead if ...
Chris H's user avatar
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9 votes
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How do you make an emergency water filter and purifier?

Gravity Filters Cone Filter Much like Charlie's gravity filter in a bottle, this filter is essentially the same, only using a cone of tree bark in place of the bottle, and using extra filtration ...
9 votes

How do you make an emergency water filter and purifier?

Here is what I have found for a very basic set up with a cheap water bottle. The water will be pored through the top through gravel, sand, charcoal and finally either a screen or another mechanism ...
Charlie Brumbaugh's user avatar
8 votes

When should I boil water before distilling it?

I still think this is off topic but I don't agree with a posted answer. If you are talking hydrocarbons they are pretty toxic to humans even in small concentrations. A spill minor compared to the ...
paparazzo's user avatar
  • 7,186
8 votes

Can any automotive fluids be made safe to drink?

None of these fluids can be made "safe" for consumption. Most of these liquids are oil based with these exceptionn: battery fluid: is a strong acid, which is diluted with water washer fluid: water ...
knitti's user avatar
  • 1,469
8 votes
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What are the most likely causes of unfilterable water contamination in upland UK areas?

Viral infection Assuming you have a quality filter which genuinely removes bacteria and protozoa, you are probably safer from viral infection than you think. Viruses are quite likely to be present ...
Tullochgorum's user avatar
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8 votes
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What is the minimum amount of water per day to survive?

According to NAP.edu, the minimal (obligatory) daily water loss for an adult is at least 1 liter (~1 quart), which includes losses by the urine, feces, insensible perspiration and breathing (but not ...
Jan's user avatar
  • 1,329
7 votes

How can I desalinate ocean water enough for cleaning or showering?

You linked to an industrial sized watermaker (75 gallons per hour) but they do come in smaller sizes for significantly less money. But think hard about how much water you actually need. I'd consider ...
Karen's user avatar
  • 4,254
7 votes
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Can sunlight be used to purify water?

It is possible, here is the Wikipedia article on it. You do have to check that the plastic in the waterbottle doesn't prevent the UV light peneatrating the bottle. Some glass or PVC materials may ...
Charlie Brumbaugh's user avatar
7 votes
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Drinking water in Dartmoor

I live by Dartmoor and walk there regularly (in fact I was up there earlier today). The moor carries a significant stock of sheep, cattle and ponies. I've heard of tests that found much of the water ...
Tullochgorum's user avatar
  • 11.7k
7 votes
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Water filters: is there always a tradeoff between longevity and safety

If the water is muddy or there are swimmers, then the usual solution is to prefilter before treating. A handkerchief is usually sufficient for filtering out all of the visible swimming bugs and sand/...
Charlie Brumbaugh's user avatar
7 votes

How can I obtain drinking water in a saline area such as the Northern Great Plains?

Distill by fuel (doesn't work well on the go) Technically you could distill the water, but this takes a long time and uses a lot of fuel. I'm not sure how many ounces of water you can distil with an ...
Loduwijk's user avatar
  • 3,556
6 votes
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Could a steam juicer be used to desalinate water?

Yes, it can as what you would do is use heat to turn the salt water to steam and then collect the steam and turn it back into liquid water. It works on the same principle as a regular distiller, and ...
Charlie Brumbaugh's user avatar
6 votes

Filtering fine silt/mud from water (not necessarily bacteria etc.)

This is only a partial answer but if you’re not drinking the water immediately you might benefit from letting it settle, especially if you can find water near where you’re camping. From https://www....
mmcc's user avatar
  • 3,466
6 votes
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How can I obtain drinking water in a saline area such as the Northern Great Plains?

I've been to the Northwestern part near Val Marie in April 2004. Carry a Supply of Water ... probably the only realistic option. Val Marie drinks reverse osmosis water and I took the advice of the ...
cbeleites unhappy with SX's user avatar
6 votes
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Water treatment for washing - are purification tablets best option, and how many are needed?

Boiling is the most effective and cheapest method of cleaning up this much water. It does require some faffing about boiling volumes, letting them cool before putting in storage containers, then ...
bob1's user avatar
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