This is Backpacking Basics and Luke is going over the importance of having a Water Purification Backup.
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Humans need roughly 2 liters of water on average per day. When out backpacking this increases depending the the type of stresses you are putting your body though. I’ve been on trips where my friends and I would consume almost 4 liters of water each!
Under extreme conditions an adult can lose 1 to 1.5 liters of sweat per hour
Humans can only go 100 hours without water at average outdoor temperatures
If it’s cooler, you can go a little longer. If you are exposed to direct sunlight, it’s less.
At least 60% of the adult body is made of it and every living cell in the body needs it to keep functioning.
Bacteria, protozoa and viruses
Never fully rely on a primary source of purification or filtration because eventually, all methods fail eventually. Possibly the product or you will make a mistake.
Carry with you a means of purifying water so that you don’t become sick and ill.
Filters can spring a leak and contaminate water that has already been processed.
Electronic means can break or batteries fail.
Etc
backup methods include :
iodine
Chlorine dioxide
Aquamira Drops
MSR Sweetwater Drops
Polar Pure
Potable Aqua
Katadyn Micropur
Household Bleach (2 drops per quart of water)