The correct and rational actions of victims who have fallen into cold water, their observance of certain rules of behavior aimed at reducing heat loss, allow the economical use of available and reserve capacity of the body in a fight with cold, which ultimately increases the life expectancy of victims.
Rules of conduct and procedures for the shipwrecked to find themselves overboard in the cold water of the open sea, actions for convulsions.
What should be the actions and rules of conduct of shipwrecked, caught in cold water? Before listing them, it should be noted that a person caught in cold water after leaving a bending ship or ship may die much earlier than hypothermia occurs. One of the causes of fatal outcomes is a violation of the function of external respiration due to extensive irritation of cold receptors of the skin.
It is manifested by rapidly developing enhanced ventilation of the lungs (hyperventilation). When quickly immersed in cold water, hyperventilation significantly increases the risk of death, since water can get into the victim’s airways when swimming. In addition, in cold water, the time of arbitrary breath holding is significantly reduced. Therefore, once for some reason, under water, the victim may involuntarily take a breath and die.
The results of the experiment, in which volunteer testers (men) participated, showed that lung hyperventilation, which occurs immediately after immersion in cold water, can be significantly reduced by means of gradual (phased) entry into it. To do this, you must first sink into the water to the waist and be in this position for at least 30 seconds, and then completely immerse and swim.
It is likely that during gradual immersion, the victims have time to form urgent adaptation mechanisms, the physiological significance of which is associated with a significant mitigation, weakening of the effects of cold on the body. In our opinion, it is advisable to include training in phased immersion programs in training programs for the survival of disasters at sea. In some cases, it will help save the lives of victims..
The procedure and behavior of the shipwrecked overboard in cold water.
In the event that there are no unforeseen means (rafts, boats) and ambulance nearby, it is necessary to reduce traffic to a minimum. This will help to avoid convective heat loss. Swimming is considered advisable only if the conditions, and, most importantly, the temperature of the water make it possible to get to the shore or rescue equipment.
It was found that a person in ordinary wet clothes can swim no more than 1,500 meters. The maximum distances that a person, depending on the temperature of the water, can swim without serious damage to health are presented in the table below.
The maximum distance that a person can swim at different water temperatures.
You should not roll over on your back if the individual rescue equipment in the neck and head has insufficient insulation. No attempt should be made to keep the body horizontal on the surface. In this case, periodic immersion of the head in water is inevitable, which will significantly increase heat loss. The head should be kept as high as possible above the water, since 50–75% of all heat loss falls on it.
In order to reduce the surface that gives off heat and to protect the areas of the body that intensively give off heat, it is necessary to adopt an “embryo pose”. The legs are bent at the knees, arms and legs pressed to the body. Studies conducted by Canadian researchers have shown that in the case of this behavior, a person can survive in water with a temperature of +10 degrees for about 4 hours, while without moving with arms and legs outstretched – up to 2.5 hours. And swimming in a horizontal position – only 1.5 hours.
Being in the water, you do not need to take off your clothes and throw off, even interfering with movements. When swimming with a life-saving bib or vest, one must remember that they have at least double buoyancy and wet clothing that seems heavy cannot significantly worsen the position of the victim. Numerous examples of emergencies indicate that even completely wet clothes partially protect against cooling in water.
So, a person in ordinary wet clothes in water with a temperature of +5.3 degrees loses heat by 25% less than naked. Woolen clothing significantly reduces heat transfer in water. The skin temperature remains 4–5 degrees higher than that of a naked person.
People in distress in the water and in close proximity to each other (this must be sought) should stick together. To do this, you need to connect the lifejackets using a tench or press them firmly on your sides, as far as individual life-saving devices allow, put your hands on each other’s shoulders and tighten your legs as tight as possible. If there are many victims, it is convenient to group 3 people each. Thanks to this, body cooling is significantly reduced..
The procedure for the occurrence of seizures in cold water.
Often, while in cold water, victims experience cramps in individual muscles. They are painful, but not dangerous, if the person in distress has behaviors that can eliminate them..
If the shipwrecked convulsions while in cold water:
1. In the muscles of both legs – you need to lie on your back and work with one hand, if possible, try to rub and massage the muscles brought together by a cramp.
2. In the muscles of the thigh – bend the leg at the knee joint and hand press the heel to the buttock.
3. In the calf muscles – it is recommended to bend the leg in the knee joint and pull the toes to your hand.
4. In the muscles of the hands – it is necessary to swim on the back, working with one leg, while raising your hands, and continuously compress and unclench your hands.
5. In the muscles of the abdomen – it is necessary to lie on your back, bend your legs at the knee joints and energetically pull them to your stomach.
Given that the cooling of victims in the water stops at temperatures close to body temperature, in almost all cases it is necessary to take measures to prevent hypothermia. When approaching the rescuers, it is necessary to attract attention by raising your hand and without relying on your voice, give signals from time to time with a whistle. The sound of the latter is heard above the water much better than screaming.
The order of behavior of victims in case of accidental falling overboard.
Special care should be taken when accidentally falling overboard. The first thing you need to do is to inflate the rescue tool by pulling the head or the starting shield of the gas spray, and by all means try to sail as soon as possible even at a small distance from the side of the vessel so as not to get under its screws.
Then you should energetically give signals with a whistle in order to attract attention, since a fall overboard, especially in the dark, can be unnoticed. Disaster-affected after taking the listed primary measures in the future should act in accordance with general recommendations.
Based on the book Encyclopedia of Survival at Sea.