iStraw Emergency Water Filter

Don’t let an illness (like one of these) spoil your next backpacking, vacation or important business trip. The iStraw Emergency Water Filter is a personal water filtration drinking straw. This means you don’t have to worry about using local tap water or ice cubes and also means that you are playing your part in helping the environment by not using plastic bottles of water that release harmful emissions into the atmosphere. iStraw is a polycarbonate straw fitted with a special membrane, which uses micro-filtration technology to clean your water rather than expensive and bad tasting water cleaning tablets. It is suitable for personal use to help protect you, your family and friends against water borne bacteria and protozoa that are present in the drinking water and ice of many countries. In this day of extensive personal and business travel it is no wonder that many travellers often incur health problems during their holiday or business trip.

The iStraw is compact, lightweight and simple to use, an essential companion for all travelers. Unlike water purification tablets, it leaves no funky aftertaste. It reduces up to 99.99999% of all waterborne bacteria, including Giardia and Cryptosporidium. When used properly, the iStraw is capable of filtering up to 500 litres of water.

• Reduces up to 99.99999% of all waterborne bacteria, including Giardia and Cryptosporidium
• Filters up to 500 litres of water
• The iStraw can be used for local municiapal tap water, streams and lakes but always refer to the instructions
• The iStraw should not be used to filter brackish or turbid water and it does not remove chemical contaminants or viruses contained in water

iStraw

What to carry in the woods

Water

A human can survive a maximum of three days without the intake of water, assuming you are at sea level, at room temperature, and a relative humidity.^[4] Depending on the climate conditions, it has been recorded that people have lasted longer than two weeks with no water supply. According to the Guinness Book of Records, the longest time a human has survived without water is 18 days.^{[citation needed]}

In cold temperatures and with rain or snow the length of survival would be greatly reduced. Length of survival also depends on amount of physical exertion. A typical person will lose 2-3 liters of water per day in ordinary conditions, but more in hot, dry, or cold weather.

A lack of water causes dehydration, resulting in lethargy, headaches, dizziness, confusion, and eventually death. Even mild dehydration reduces endurance and impairs concentration, which is dangerous in a survival situation where clear thinking is essential. Your body requires 4L to 6L of water or other liquids each day in the wilderness to avoid dehydration and to keep your body functioning properly.^[4]

Dark yellow or brown urine indicates dehydration. Because of these risks, a safe supply of drinking water must be located as soon as a shelter is built (or even before, depending on conditions). In a survival situation, any water supply may be contaminated with pollutants or pathogens (see Potability of backcountry water). Although little can be done to remove molecular contaminants, particles and microorganisms can be removed and/or killed (see Portable water purification).

There are some plants which will provide you with survivable sources of water. Most tree roots and vines contain lots of water, and can be purged by breaking into 3 ft. sections, and standing upright above a water catcher. Avoid any vegetable liquids which are cloudy, milky in appearance, or colored in any way.

Water can be gathered in numerous ways. In areas of abundant moisture, water can be scooped out of a creek or pond. Rainwater (which is typically safe to drink) can be caught in makeshift containers. If these easy sources are not available, a bit more ingenuity will be necessary. Water can be collected from condensation traps or solar stills. Clothing can be used to collect dew from vegetation. Tie a tee shirt to your ankle and walk through dew-covered grass in the morning or evening, wring out water and collect. This is a very effective water procurement method.

Although you cannot drink salty seawater, if you are near the beach, you can dig a sand well on the opposite side (from the sea) of a windblown dune. Below sea level, the sand well will fill with drinkable water. It may taste salty or brackish, but the sand acts as a filter reducing the salt content the further you dig inland.

Stagnant water can be made drinkable by filtration through a sieve of charcoal.

Animal blood is not suitable for rehydration as it may be diseased. In addition, because of the nutrients it contains, it requires energy to digest. Mammals all have blood-borne pathogens so the animal must also be cooked. Urine contains salt and other toxins, which also makes it unsuitable to drink, although it can be refined in a solar still.

A common survival myth is that cacti can be sliced open to obtain water. While some cacti do have fluid inside, it is a highly acidic solution and would induce vomiting if drunk.^{[citation needed]} Some Cacti are very toxic and would kill you if drunk.

Many birds, mammals, and some insects, such as bees, ants, and mason flies, are reliable indications of water, either through a stream or a soaked patch of earth.

There are differences of opinion on whether or not to ration water when you have a limited supply. The U.S. Army survival manual recommends that you use your water whenever thirsty to avoid “voluntary” dehydration.^[5] Other groups recommend rationing water through “water discipline”.^[6]

In extremely dry environments, it is necessary to take extra care to prevent water loss by:

• Breathing through the nose to prevent water vapor escaping through the mouth
• Not smoking
• Resting in the shade and avoiding strenuous labor during sunny, hot periods
• Not eating too much (the human body uses a lot of water to digest food – especially fats and proteins)
• Not drinking alcohol, which hastens dehydration

You can gather moisture in these ways:

• Transpiration – collecting transpired water via a plastic bag.
• Using a Solar still
• Melting ice
• Well water
• Desalination
• Utility-Scale Atmospheric Water Gathering
• Harvesting/collecting dew from plants and grasses

from wikipedia.com

Water Filtration Systems

WATER FILTRATION DEVICES

6-35. If the water you find is also muddy, stagnant, and foul-smelling, you can clear the water—

• By placing it in a container and letting it stand for 12 hours.
• By pouring it through a filtering system.

NOTE: These procedures only clear the water and make it more palatable. You will have to purify it.

6-36. To make a filtering system, place several centimeters or layers of filtering material such as sand, crushed rock, charcoal, or cloth in bamboo, a hollow log, or an article of clothing (Figure 6-10).

Figure 6-10. Water Filtering Systems

6-37. Remove the odor from water by adding charcoal from your fire. Charcoal is also helpful in absorbing some agricultural and industrial chemicals. Let the water stand for 45 minutes before drinking it.

Water Purification

6-29. Rainwater collected in clean containers or in plants is usually safe for drinking. However, purify water from lakes, ponds, swamps, springs, or streams, especially the water near human settlements or in the tropics.

6-30. When possible, purify all water you get from vegetation or from the ground by boiling or using iodine or chlorine. After purifying a canteen of water, you must partially unscrew the cap and turn the canteen upside down to rinse unpurified water from the threads of the canteen where your mouth touches.

6-31. Purify water by the following methods:

• Use water purification tablets. (Follow the directions provided.)
• Place 5 drops of 2 percent tincture of iodine in a canteen full of clear water. If the canteen is full of cloudy or cold water, use 10 drops. (Let the canteen of water stand for 30 minutes before drinking.)
• Use 2 drops of 10 percent (military strength) povidone-iodine or 1 percent titrated povidone-iodine. The civilian equivalent is usually 2 percent strength, so 10 drops will be needed. Let stand for 30 minutes. If the water is cold and clear, wait 60 minutes. If it’s very cold or cloudy, add 4 drops and wait 60 minutes.
• Place 2 drops of chlorine bleach (5.25 percent sodium hypochlorite) in a canteen of water. Let stand 30 minutes. If the water is cold or cloudy, wait 60 minutes. Remember that not all bleach is the same around the world; check the available level of sodium hypochlorite.
• Use potassium permanganate, commonly marketed as Condy’s Crystals, for a number of applications, including emergency disinfection of water. The crystals are of a nonuniform size, so you must judge the actual dosage by the color of the water after adding the crystals. Add three small crystals to 1 liter (1 quart) of water. If the water turns a bright pink after waiting 30 minutes, the water is considered purified. If the water turns a dark pink, there is too much potassium permanganate to drink safely. Either add more water to dilute the mixture or save it for use as an antiseptic solution. If the water becomes a full red, like the color of cranberry juice, the solution may be used as an antifungal solution.
• Boil your drinking water. This is the safest method of purifying your drinking water. By achieving a rolling boil, you can ensure that you are destroying all living waterborne pathogens.

6-32. By drinking nonpotable water you may contract diseases or swallow organisms that can harm you and may easily lead to potentially fatal waterborne illnesses.

6-33. Two of the most prevalent pathogens found in most water sources throughout the world are—

• Giardia, which causes Giardiasis (beaver fever). It is characterized by an explosive, watery diarrhea accompanied by severe cramps lasting 7 to 14 days.
• Cryptosporidium, which causes Cryptosporidiosis. It is much like Giardiasis, only more severe and prolonged, and there is no known cure but time. Diarrhea may be mild and can last from 3 days to 2 weeks.

NOTE: The only effective means of neutralizing Cryptosporidium is by boiling or by using a commercial microfilter or reverse-osmosis filtration system. Chemical disinfectants such as iodine tablets or bleach have not shown to be 100 percent effective in eliminating Cryptosporidium.

6-34. Examples of other diseases or organisms are—

• Dysentery. You may experience severe, prolonged diarrhea with bloody stools, fever, and weakness.
• Cholera and typhoid. You may be susceptible to these diseases regardless of inoculations. Cholera can cause profuse, watery diarrhea, vomiting, and leg cramps. Typhoid symptoms include fever, headache, loss of appetite, constipation, and bleeding in the bowel.
• Hepatitis A. Symptoms include diarrhea, abdominal pain, jaundice, and dark urine. This infection can spread through close person-to-person contact or ingestion of contaminated water or food.
• Flukes. Stagnant, polluted water—especially in tropical areas—often contains blood flukes. If you swallow flukes, they will bore into the bloodstream, live as parasites, and cause disease.
• Leeches. If you swallow a leech, it can hook onto the throat passage or inside the nose. It will suck blood, create a wound, and move to another area. Each bleeding wound may become infected.