Hydration pack and its uses

A hydration pack or drink pouch is a hydration system constructed as a backpack or fanny pack that contains a reservoir or "bladder" usually made of rubber or flexible plastic.The reservoir contains a capped spout for filling liquid and a hose that allows the wearer to drink hands-free.Most hose ends have a "bite valve" that opens when the user bites in; the valve can be protected with a dust cover. Some water bags are insulated to keep the water from freezing or getting hot.

Uses

The volume of the reservoir and the pack that carries it can vary widely depending on the purpose of the hydration pack.Some backpacks are very small and minimalist, designed to keep weight as low as possible and keep you safe while running or cycling, while others are better suited for backpacking and hiking, with larger interiors.However, since each liter of water weighs 1 kg (8.3 lbs/US gal), it is impractical to carry more than a few liters in most cases; typical reservoirs are between 1-3 liters even for very large backpacks between.In addition to hydration, the water reservoir can be used for washing dishes or equipment, or for showering.In some cases, a pressurized water bag is used to provide a flow of water powerful enough to wash effectively, or the water bag can be suspended from a high place (such as a tree branch) to use gravity to create water pressure.

Hydration bladders are commonly used for outdoor recreational activities such as hiking, biking, and kayaking, as well as military exercises.Most field packs designed for backcountry or military use include a user-supplied hydration bladder.Since hydration packs are airtight, they are widely used in CBRN protected situations with full face respirators, allowing for full mobility and fluid/nutrient supply - unlike water bottles that must be turned upside down.In addition, there are acid and chemical resistant versions for military and police use, such as "Camelbak Chem-Bio".