by Cody Lundin
Horrifying Humidity
Many of you reading this live in locales that are hot and humid. Humidity is a true killer, and when it approaches 70 percent or more it completely impedes the body's evaporation process. High humidity levels will make many of the water tricks in this book useless when trying to "make nice" with hot outdoor temperatures. As the body's main cooling mechanism (the evaporation of sweat) is ineffective during periods of high humidity, it is extremely important that you monitor your behavior and don't do highly physical tasks during the heat of the day. If it's already hot outside, and your sweat won't evaporate due to high humidity, and you create excess metabolic heat by working like a crazy person during the hottest part of the day, you're asking for trouble.
Going Under Cover
Obviously, it's hotter to stand in the sun than in the shade. Any shade allowing protection from direct solar radiation will drastically make your living environment cooler. Rooms not oriented to the north, yet featuring plenty of overhead shade cover from trees, buildings, or whatever, may be cooler inside than the sun-beaten roofs of exposed north-facing rooms, especially if you have crummy insulation in your attic or ceiling. Pay attention someday to how and when the summer sun pummels your home and make mental notes for the future. Tarps, opaque rolls of plastic, blankets, or other shade-producing items can be strung up over parts of your home to eliminate some or all direct sunlight. Along with the created shade, the dead air space produced between the tarp and the house acts as bonus insulation from hot temperatures. Think of your home as a body similar to yours. If it stands out in direct sunlight all day long, it will be much hotter than if it has access to shade. It's very common in the desert to see mobile homes with entire carports erected over the mobile home itself for the same benefit. This is the same reason that many ancient Native American tribes in the Southwest built stone-stacked pueblos under natural rock overhangs. If your house is cooler on the outside, you will be cooler on the inside.
Covering Windows with Space Blankets
I've mentioned this several times but now I'll get specific. Taping a space blanket to the inside of your home's window will reflect away direct shortwave radiation from the sun, as well as hotter long-wave radiation from the boiling outside environment. Smaller, more reflective space blankets will be easier to use for this application than the heavier grommeted type. In truth, while the shinier the material the more it will reflect, any reflective surface can be used. Tape up tinfoil if that's all you have, but keep the foil flat and neat and don't scrunch it up, thereby eliminating some of the tinfoil's reflective value, and put the shinier side out.
Whatever you use, the reflective surface should be taped onto the window itself if possible, yet done so in a way that will allow you to remove it when necessary without ripping up the material. If the reflective surface is hung or taped a few inches away from the window itself, radiation will heat up the space between the reflective surface and the window. This heat gain will eventually leak into the room.
Your home's (or any shelter's) main purpose is to help thermoregulate your core body temperature in hot and cold temperatures.
Avoiding hypothermia (low body temperature) and hyperthermia (high body temperature) is a major factor in your survival. Know the signs and symptoms of both for yourself and others.
Being properly dressed by having adequate clothing and staying hydrated by storing and drinking sufficient water are the easiest ways to thermoregulate core body temperature and stay warm or cool during temperature extremes.
Your body loses or gains heat from the environment through convection (wind and moving water), conduction (touching a hot or cold object), radiation (shortwave radiation from the sun and long-wave radiation from everything else), evaporation (sweating), and respiration (breathing). Pay attention to the same physics when improvising or setting up an alternative shelter such as a tent, tarp, or RV.
Your home could be partially or completely destroyed during a disaster. Check for structural damage before entering the home. If you choose to reenter, make sure it's not in danger of collapsing. Ultimately, this inspection will need to be done by a professional. If you do decide to reenter your home, turn off any outside gas lines and let the house air out for several minutes to remove potential escaping gas. When entering the home, don't use open flames as a light source. Instead, use a battery-operated flashlight or some other nonfuel burning light source.
Have portable, alternative shelter option(s) that are easy to set up under stress such as a tent or tarp in case you need to evacuate your home or your home is damaged in a disaster.
In Cold Weather: Maximize the warmest room(s) in the house and isolate it from the rest of the colder home. As a general rule, smaller south-facing rooms with windows will be warmer on cold, sunny days than other rooms in the house. Direct sunlight hitting thermal mass areas such as a concrete floor will re-radiate more heat at night than the same floor covered with a throw rug. Close and insulate under doors with extra clothing or towels, cover windows during nighttime hours with clear plastic and/or space blankets, and make group "sleeping forts" to maximize body heat. Remember that warm air rises, and sleeping next to a family member will be warmer than sleeping alone.
For your safety and maximum efficiency, woodstoves and fireplaces should be serviced yearly by a professional whether they have been used or not. Have an adequate supply of firewood or pellets on hand, stored in a safe location away from the house.
Danger! Beware of deadly carbon monoxide fumes when using any fuel-burning heating source indoors such as fireplaces, woodstoves, or propane, kerosene, natural gas, or coal-burning space heaters. All yellow and orange flames produce poisonous carbon monoxide. Install battery-powered carbon monoxide detectors and alarms near all rooms where people will be sleeping.
Space heaters should be vented to the outside and kept in good working order. Keep all heaters at least three feet away on all sides from all combustible materials. Use caution with space heaters around children and pets and store all fuels in approved containers safely away from the home.
In Hot Weather: Maximize the coolest room(s) in the house and isolate it from the rest of the hotter home. Look for north-facing rooms, draw window blinds, and utilize space blankets or tinfoil to keep out the sun. Close doors, insulate higher openings in rooms to keep out rising hot air, and create shade wherever possible. Open windows at night to let out trapped heat and let in cooler nighttime air and close them again before outside temperatures rise. Cooler air sinks, so go low and wet down clothing and/or sheets that can be hung between rooms or in doorways to increase evaporative cooling.
Beware of high humidity levels when it's hot outside. Humidity levels of 70 percent or greater severely impede the evaporation of sweat from your body. Wait for cooler early morning or late evening temperatures before doing heavy physical exercise.
13
WONDERFULLY Wet and Wanted WATER
"Many of the wars of this [twentieth] century were about oil, but the wars of the next century will be about water."
—Ismail Serageldin, former World Bank Vice President, 2000
For short- and long-term survival, virtually nothing will eclipse the importance of potable water for you and your loved ones. Ignore this fact and you will meet death. Over dramatic? I wish it were. Water is a biological necessity down to the cellular level. It is not an optional item. It is general knowledge that water accounts for nearly two-thirds of the human body's total weight. Research has shown that the older we get, the drier we become. Floating around in the womb, overall body water content is more than 80 percent. As infants, our body water content drops to around 73 percent. In young adults, the body contains roughly 65 percent water, 70 percent in the muscles and 50 percent in fat deposits. Between forty and sixty years old, water content drops to 55 percent for males and 47 percent for females. After sixty, the rate drops even further, 50 percent for males and 45 percent for females.
Water has several amazing prop
erties, including the fact that it's an excellent solvent. Water dissolves a remarkable number of inorganic and organic molecules. When dissolved, molecules break apart to form a solution. Living activities on a cellular level take place either dissolved in fats or water. Water has a high heat capacity, meaning it requires a lot of energy to heat it up, or cool it down, so it can handle a wide variety of outside temperature fluctuations within the cell before problems arise. The water in your blood helps the circulatory system get rid of excess heat, or distribute heat to wherever it's needed during the cold. Digestion and metabolism are waterbased processes, and water lubricates the joints and helps eliminate waste products from the body as well. Water is even required for the simple act of breathing, as the lungs need moisture to oxygenate blood and rid the blood of excess carbon dioxide. Nearly 70 percent of the Earth's surface is covered in water. It is therefore no exaggeration to say that water is life itself.
In desert climates, temperatures can be so hot and dry that people don't seem to perspire. Since they're "not sweating," they underestimate how hot the outside temperature really is, thereby reducing the urge to drink. The truth is revealed by putting your hand on your skin for a minute or two. Lift your hand and you'll find it's sodden with sweat, proof enough of the body's desperate attempt to keep the brain and internal organs cool. In extreme hot temperatures, unprotected skin instantly loses moisture. The skin is the largest organ of the body, and directly responsible for the evaporation of sweat, thereby helping to keep your inner temperature at a comfortable 98.6 degrees F (37 degrees C).
A person at rest, doing nothing, loses from two to two and a half quarts of water every day. If your home is located in a hot part of the country, be forewarned that you and your family will use much more water than this. Some of this water loss, about 600 to 900 milliliters, happens simply to keep our skin supple and healthy and is called insensible perspiration. In extreme hot temperatures, it's possible to lose a gallon of water an hour in sweat. That's an unbelievable 8.3 pounds! This heinous fact should make apparent that the "standard survival recommendation" of carrying one gallon of water per person per day in the desert is completely bogus. When living, recreating, or traveling in hot temperatures, I recommend at least three gallons of water per person per day, more if the terrain, temperatures, or activities undertaken are extreme. Seeing as how the average American individually uses 116 to 220 gallons of water every day, with some wealthy communities in my arid state using in excess of 400 gallons per person daily, it isn't hard to see our gross neglect regarding the importance of conserving this precious fluid. (Note: The average African family uses about five gallons of water each day.) Pitifully, the National Drinking Water Alliance estimates that up to 50 percent of the water that families use could be saved by implementing simple conservation methods like low-flow shower heads and low-flush toilets.
For every quart of sweat you lose, your heart rate raises about eight beats per minute, your cardiovascular system becomes more stressed, and your cooling system declines. In other words, before dehydration kills you, it greatly impedes your physical and psychological performance.
Deadly Dehydration
Seventy-five percent of Americans are chronically dehydrated. Thirty-seven percent mistake the thirst mechanism for hunger pangs. Lack of hydration is the number one trigger of daytime fatigue. If you live in an arid region or one with oppressively high humidity, you know how tough it is to remain hydrated. Doing so takes a lot of work! Although at times it's hard to remember to drink, and then to drink enough, it is critical for your physiology and psychology that you remain maximally hydrated.
Dehydration is deadly in hot and cold weather. When the blood in your circulatory system loses water, it gets thicker. Thick blood circulates more slowly and is harder for the heart to pump, and in regard to temperature regulation, it hinders the body's ability to lose excess heat or circulate needed heat. When the volume of blood and extra cellular fluids decreases, water is literally sucked from the cells, causing them to shrink, thereby damaging cell membranes and the proteins inside. Platelets actually stick together in the blood due to a lack of plasma. The result is an increase in the naturally occurring salts in the remaining body fluids. Normal body fluid has a salt concentration of 0.9 percent. In contrast, urine contains 2 percent salt, plus toxic urea, while seawater has a whopping 3.9 percent. Many researchers feel that rising salt concentrations within the body are responsible for the punishing side effects of dehydration.
* * *
HOW YOUR BODY LOSES WATER
Factors Inside the Body
Body Water Loss
Factors Outside the Body
-Physical exertion
-Certain medications
-Illness (fever)
Increased sweating
-Hot temperatures
-Direct short-or long-wave radiation (sunlight/fire)
-High humidity
-Physical exertion
-Illness (fever)
-Breathing through mouth
Increased respiratory loss
-Low humidity
-High wind speed
-Cold temperatures
-Hypothermia
Increased urine loss
-Diuretics: alcohol/coffee/tea/certain medications
-Diarrhea
-Vomiting
Increased bowel and stomach loss
Increased insensible perspiration
-Hot temperatures
-Low humidity
-High wind speed
-Bleeding
Increased blood loss
Increased digestive loss
-High protein, fat, and sodium diet
* * *
Exposure to cold weather without protective clothing or some other way to remain warm increases urine production. When surface blood vessels constrict from the cold, reducing the circulatory system and increasing blood pressure, pressure sensors in the body perceive an increase in volume and stimulate urine production. To make things worse, when outside temperatures fall, so does your kidneys' ability to concentrate urine, and the end result is that you lose even more water.
Body functions are severely limited if you lose 10 percent of your weight due to dehydration, yet physical, mental, and emotional impairment is manifest with the slightest loss of water, especially in the heat. Losing just 2 percent of body weight in water compromises your overall judgment by 25 percent and severely limits physical endurance. Being outside in temperatures of 100 degrees F (38 degrees C) or more will cause you to lose another 25 percent. To summarize, if you live in hot temperatures and are a quart and a half low on water, you are operating at half the person you usually are! In Arizona and other arid parts of our nation and world, this is a very common occurrence. The water in your body affects your circulation, metabolism, good judgment, and overall attitude, just like the emotion fear.
How Much Water?
So how do you know if you have enough water in your system? Thirst should never be an indicator of when or how much to drink. Being thirsty is a sign that you're already a quart to a quart and a half low. To make matters worse, somewhere down the line in Dehydrationville, the thirst mechanism stops working altogether.
The best way to tell if you're maximally hydrated is the color of your urine. It should be as clear as the water you drink, with no color whatsoever. Certain medications and vitamins, especially B vitamins, color urine. The volume and frequency of urine produced by someone who has been drinking copiously are other hydration indicators, although not as reliable as color. Using the three together will provide the most effective guesstimating as to when and how much you and your family should drink.
There is no adaptation to dehydration. Military personnel have learned the hard way that "being tough" is not an acceptable substitute for water. Astute military commandeers have recognized for years that when personnel operate in hot temperatures, even when abundant water is readily available, soldiers will not drink enough water to avoid dehydr
ation unless they are forced to drink. This oddity is called "involuntary dehydration" and I experience it all the time with students on my survival courses. Think about it for a minute. When you are thirsty, meaning that your body is already a quart or more low on water, you have the urge to drink. To allay your thirst, you drink a few swallows of water and, voila, you're no longer thirsty, but your body is still dehydrated and will continue to grow more so unless you force yourself to drink a quart or more of water. If you live in hot temperatures, drink more water than your body seems to want. Watch your family like a hawk, especially older people, small children, and babies for the signs and symptoms of dehydration. It only takes one person to compromise the whole group. Exotic methods for procuring water such as solar stills are notoriously unreliable and can hasten your death.
