MPI Outdoors


You heard about it - now read about it.

Wind Chill factors measure the effect of the combination of temperature and wind speed on human comfort. It is important to remember that these chill factor temperatures do not have the same effect on inanimate objects, animals or on plants. Wind Chill does not humans who are sheltered from the wind, such as those wrapped up in a SPACE® Brand BLANKET, or inside the EXTREME Pro-Tech Bag or Vest. The current formula to determine Wind Chill uses advances in science, technology, and computer modeling to provide a more accurate, understandable, and useful formula for calculating the dangers from winter winds and freezing temperatures. The following is a link to the National Weather Service site, where you can view the wind chill chart, get plenty of additional information and you can even enter the temperature and wind speed and it will figure out the specific wind chill temperature for you.

What is it and how does it affect your outdoor performance.

Hypothermia is a temperature related disorder. Therefore, it is necessary to understand human physiology as it pertains to temperature stress.

Man is considered to be a tropical animal. Normal functioning of the human animal requires a body temperature of 98.6 degrees Fahrenheit. Comfortable human survival using only that protection from temperature stress, which is provided physiologically at birth, would therefore require an environment providing a temperature of 98.6 degrees Fahrenheit.

The body can self-compensate for small upward or downward variations in temperature through the activation of a built-in thermoregulatory system, controlled by temperature sensors in the skin.

The response to an upward variation in body temperature is the initiation of perspiration, which moves moisture from body tissues to the body surface. When the moisture reaches the surface it evaporates, carrying with it a quantity of heat. The explanation for a person becoming thirsty when exposed to a hot environment for a period of time is that fluids lost due to perspiration must be replaced.

The response to a downward variation in body temperature is shivering, which is the body's attempt to generate heat. Shivering is an involuntary contraction and expansion of muscle tissue occurring on a large scale. This muscle action creates heat through friction.

Hypothermia is also considered the clinical state of sub-normal temperature when the body is unable to generate sufficient heat to efficiently maintain functions.

Many variables contribute to the development of hypothermia. Age, health, nutrition, body size, exhaustion, exposure, duration of exposure, wind, temperature, wetness, medication and intoxicants may decrease heat production, increase heat loss, or interfere with thermostability.

The healthy individual's compensatory responses to heat loss via conduction, convection, radiation, evaporation and respiration may be overwhelmed by exposure. Medications may interfere with thermoregulation. Acute or chronic central nervous system processes may decrease the efficiency of thermoregulation.

Here are the definitions of the main causes of body heat loss.

Conduction: Direct transfer of heat by contact with a cooler object and the conduction of heat to the cooler object.

Convection: Cool air moving across the surface of the body, heat transferred to the cool air, warming it and cooling the body.

Radiation: Heat radiated outward from the warm body to the cooler environment.

Evaporation: The loss of heat through the process of removing water from the surface of the body through vaporization.

Respiration: Air inside your lungs raised to current body temperature and then exhaled.

Each of these causes of heat loss play a role in the development of hypothermia, depending on clothing, head cover, wind, weather, etc.

Note: ALWAYS GET PROFESSIONAL MEDICAL HELP AS SOON AS POSSIBLE, this is just an overview so hopefully you can recognize the symptoms and only if needed address the treatment.

Impending Hypothermia:

Due to physiological, medical, environmental, or other factors the person's core temperature has decreased to below 98.6 degrees. The person will increase activity in an attempt to warm up. The skin may become pale, numb and waxy. Muscles become tense, shivering may begin but can be overcome by activity. Fatigue and signs of weakness begin to show.

Mild Hypothermia:

The person has now become a victim of hypothermia. The core temperature has dropped to well below 98.6 degrees. Uncontrolled, intense shivering begins. The victim is still alert and able to help self, however movements become less coordinated and the coldness is creating some pain and discomfort.

Moderate Hypothermia:

The victim's core temperature has now dropped to below 90 degrees F. Shivering slows or stops, muscles begin to stiffen and mental confusion and apathy sets in. Speech becomes slow, vague and slurred, breathing becomes slower and shallow, and drowsiness and strange behavior may occur.

Severe Hypothermia:

Core temperature is now below 86 degrees F. Skin is cold, may be bluish- gray in color, eyes may be dilated. Victim is very weak, displays a marked lack of coordination, slurred speech, appears exhausted, may appear to be drunk, denies problem and may resist help. There is a gradual loss of consciousness. There may be little or no apparent breathing, victim may be very rigid, unconscious, and may appear dead.

Note: ALWAYS GET PROFESSIONAL MEDICAL HELP AS SOON AS POSSIBLE, this is just an overview so hopefully you can recognize the symptoms and only if needed address the treatment.

Impending Hypothermia:

Seek out or build a shelter to get the person out of the cold, windy, wet environment. Wrap in a blanket or additional dry clothes if possible. Start a fire to provide warmth. Provide the person with a hot drink (no alcohol, coffee or tea). The person should feel better and start to recover from the present condition quickly.

When signs of recovery are evident---GET OUT OF THERE IMMEDIATELY.

Mild Hypothermia:

Remove or insulate the patient from the cold environment, keeping the head and neck covered. This prevents further heat loss and allows the body to re-warm itself. Provide the person with a warm, sweetened drink (no alcohol, coffee or tea) and some high-energy food. Limited exercise may help to generate some internal heat, but it could deplete energy reserves, so be careful.


Moderate Hypothermia:

Remove and insulate the person from the cold environment, keeping the head and neck covered. Apply mild heat (comfortable to your elbow) to the head, neck, chest, armpits and groin of the patient. Use hot water bottles, wrapped Thermo-Pads, or warm moist towels. It is possible that you may have to continue this treatment for some time. Offer sips of warm, sweetened liquids (no alcohol, coffee or tea) if the patient is fully conscious, beginning to re-warm and be sure they are able to swallow.

Get this person as quickly and as safely as possible to a physician.

Severe Hypothermia:

At this point you should be on your way to or at a hospital.

Place the afflicted person into a pre-warmed sleeping bag along with one or two other people. Skin to skin contact in the areas of the chest (ribs) and neck is effective. Exhale warm air near the patient's nose and mouth, or introduce steam into the area. Try to keep the patient awake, ignore pleas of "leave me alone, I'm ok". The person is in serious trouble at his point; keep a close, continuous watch over him/her. Apply mild heat, with the aim of stopping temperature drop, not re-warming. If patient has lost consciousness be very gentle, as by now the heart is extremely sensitive. Always assume the patient is revivable never ever give up. Check for pulse at the carotid artery. If, after two minutes you find no pulse check on the other side of the neck for two minutes. If there is any breathing or pulse, no matter how faint, do not give CPR but keep very close watch for changes in vital signs. If no pulse is found begin CPR immediately, stopping only when the heart begins to beat. Medical help is imperative--hospitalization is needed.

Treatment of hypothermia should be approached ONLY with great knowledge and care.

It is too easy to cause more harm than good by using the wrong treatment. If you cannot distinguish the level of hypothermia through visible signs and symptoms then you should assume severe hypothermia and expend every minute of effort to get to a hospital.

New Mosquito Netting!
New Extreme!
All Weather Blanket (Space)
Emergency Blanket (Space)
Easy Focusing Headlamp
Safety Flasher
Mini-Giant Focusing Lamp
Northwoods Lights
Seabrook Waterproof Lights
Pathfinder LED

Let's get technical | Survival basics | 5 basic survival skills | Facts on Fire | Kids Survival Kit | Your First Aid Kit | First Aid Primer
Feet Facts | Your Personal Survival Kit | Collection of Outdoor Knowledge | Other Sites of Possible Interest |
Equipment checklist
Signal mirrors | Pre-trip planning | Outdoor Signaling | A balloon does what?
| Look Before You Go | Fun Flashlight Facts | "Off Season" Projects

Gear Products - Space® All Weather blanket | Space® Emergency Blanket | Space® Emergency Bag | Emergency Strobe™
Safe Signal™ Day/Night Signal Mirror
| You CAN Survive™ | Esbit® Solid Fuel | Where to find MPI Products

Lighting Products - Easy Focusing Headlamp | Safety Flasher
Mini-Giant Focusing Lamp
| Northwoods Lights | Seabrook Waterproof Lights