Environmental Hazards and the physical effects on the body.
The environment and it's effects on the body, cold, heat, wind rain, being soaking wet, parching dryness of the desert, high humidity of coast or swamps, lightning, and your altitude. During normal times in civilization may only be and inconvenience, add this to hiking or a grid down scenario, and any of these could become life threatening. The length of time exposed to the elements and the mentality or drive, as well as the physical condition of the person may be compounded. If you are out on a scout or hiking mid summer in FL. and you injur yourself and have to spend the night in the elements, no problem, painful night with probably some mosquito bites, as long as there is no wind and rain. That same trip in the fall of the year back in the Mountains of say TN. with a light wind and a drizzle, could prove fatal. You must also have food and water, shelter.
Windchill
The cooling effects of windchill are noticed at any given temperature and wind speeds. Wearing clothing that is wind proof will stop windchii in most cases.
The 4 main causes of heat loss
• Convection- heat is lost from the body by water or moving air.
• Conduction- direct transfer of heat from the body to the cold ground or from wet clothes.
• Evaporation- water or sweat evaporates from the body.
•Radiation- loss of heat from the body to a cooler environment, heat loss in cold, dark night with low wind is significant and impacting on your mental process.
Sources of heat gain
• Shivering- is the first form of heat gain and can increase temperature five fold, this also uses up energy and oxygen to maintain this.
• Blood vessel constriction- skin and extremity constrict, this shunts blood to the core. This is where the blood is needed,( brain, heart, kidneys, and liver) this reduces heat loss through the skin.
• Radiation- will come from a fire, hot engine, sun.
• Exercise- can rewarm the body, approximately 75% energy from use of muscles is heat.
• Food- Carbs provide quick energy, proteins provide superior long term energy and are slower to release usually at the cost of body weight.
• Insulation- is your first line if defense, this works by trapping your own body heat. Windproof, water repelling clothing should be worn as an outer wear trapping in the warm air and reducing the effect of, cconvection, conduction, and also evaporation.
Well I have rambled long enough! Hope this is a help.
Next is Hypothermia
Good luck, be safe, God bless
