42
votes
Accepted
How much sea water can I safely drink?
How much sea water can I safely drink? = None
If you drink sea water, how much fresh water do you need to drink to off set the sea water you drank? = 2.8 units of distilled water per 1 unit of sea ...
- 30.3k
37
votes
Accepted
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 ...
- 26.1k
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 ...
- 471
35
votes
Accepted
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/...
- 1,543
34
votes
Accepted
In a survival situation, should I drink unpurified water?
Dehydration will very quickly reduce your ability to undertake the activities required to survive and so finding and conserving water should be a very high priority in any survival situation.
...
- 6,202
24
votes
Accepted
Does a life-straw replace my water while hiking?
Generally speaking, no.
Arguably you should never go for out for any kind of extended exhausting activity without ensuring proper hydration, i.e. packing enough fluids at least for your immediate ...
- 12.7k
19
votes
Accepted
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 ...
- 5,168
14
votes
Why are people so worried about Giardia?
I'm going to chime in on a more practical answer. The question is not "What is the scientific case for Giardia". The question is "Why are people so scared of it?" "Or why is everyone so scared of it ...
- 32.1k
14
votes
Accepted
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*
...
- 1,778
13
votes
Accepted
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 ...
- 23.5k
13
votes
Accepted
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 ...
- 69.2k
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 ...
- 9,668
12
votes
Accepted
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 ...
- 4,384
11
votes
In a survival situation, should I drink unpurified water?
Dehydration will kill you before Giardia or cholera does. So, I'd first take a measure of where I am, do I absolutely need to drink the water is question, or is there any other better (safer, need not ...
- 31.7k
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 ...
- 7,156
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 ...
- 613
10
votes
Accepted
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 ...
- 9,664
9
votes
Accepted
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 ...
- 69.2k
9
votes
Why are people so worried about Giardia?
Why are People so Worried About Giardia?
Because giardia is commonly found in backcountry water and it is known to make some people very sick. The EPA says [giardia] "Cysts have been found all months ...
- 530
9
votes
Accepted
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 ...
- 26.1k
8
votes
Why are people so worried about Giardia?
Some excellent research-based answers here, so I'll focus on the practical implications.
First, and most importantly:
Most intestinal infections in the backcountry aren't caused by
bad water - ...
- 11.7k
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 ...
- 7,156
8
votes
Accepted
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 ...
- 11.7k
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 ...
- 1,451
8
votes
Accepted
Can any automotive fluids be made safe to drink?
There are three fluids in your car that contain water: the battery electrolyte, the washer fluid, and the coolant. Everything else is hydrocarbon-based, and in a properly-functioning car, contains no ...
- 2,930
8
votes
Accepted
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 ...
- 1,329
7
votes
What micron level is needed to properly filter viruses from water?
Let's look at the absolute here.
The hepatitis B virus is 0.042 microns in length; this is about as small as viruses get (http://www.who.int/csr/disease/hepatitis/whocdscsrlyo20022/en/index2.html). ...
- 284
7
votes
Accepted
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 ...
- 11.7k
Only top scored, non community-wiki answers of a minimum length are eligible