Health Risks
This type of parachuting technique can be dangerous. At high altitudes of the Earth's atmosphere (greater than 22,000 feet ), the partial pressure of oxygen (required for human respiration) is low. Lack of pressure can lead to hypoxia. Also, rapid ascent in the jump aircraft without all nitrogen flushed from the bloodstream can lead to decompression sickness (also known as caisson disease or "the bends").
A typical HALO exercise will require a pre-breathing period (30–45 minutes) prior to jump where the jumper breathes 100% oxygen in order to flush nitrogen from their bloodstream. Also, a HALO jumper will employ an oxygen bottle during the jump. Danger can come from medical conditions affecting the jumper. For example, cigarette smoking, alcohol and drug use (including histamine antagonists, sedatives, and analgesics), anemia, carbon monoxide, fatigue and anxiety can all lead to a jumper being more susceptible to hypoxia. In addition, problems with the oxygen bottle and during the changeover from the pre-breather to the oxygen bottle can result in the return of nitrogen to the jumper's bloodstream and, therefore, an increased likelihood of decompression sickness. Theoretically, a single breath of atmospheric air may elevate the jumpers arterial nitrogen level to dangerous levels. A jumper suffering from hypoxia may lose consciousness and therefore be unable to open his parachute. A jumper suffering from decompression sickness may die or become permanently disabled from nitrogen bubbles in the bloodstream, which causes inflammation of joints.
Another risk is from the low ambient temperatures prevalent at higher altitudes. At an altitude of 35,000 feet, the jumper faces temperatures of –45 °C (–50 °F), and can experience frostbite. However, HALO jumpers generally wear polypropylene knit undergarments and other warm clothing to prevent this.
Read more about this topic: High Altitude Military Parachuting
Famous quotes containing the words health and/or risks:
“The philanthropist too often surrounds mankind with the remembrance of his own cast- off griefs as an atmosphere, and calls it sympathy. We should impart our courage, and not our despair, our health and ease, and not our disease, and take care that this does not spread by contagion.”
—Henry David Thoreau (1817–1862)
“The amount of it is, if a man is alive, there is always danger that he may die, though the danger must be allowed to be less in proportion as he is dead-and-alive to begin with. A man sits as many risks as he runs.”
—Henry David Thoreau (1817–1862)