When your body starts to get very hot, your pores will open and your retained body fluid starts to exit, sweating. This is the body’s air conditioning system and works much like an evaporative cooler. If the body gets too hot, then it starts to shut down looking for ways to reduce the heat. If it’s not done then this will result in the person eventually dying.
Treating Hypothermia
- Put on additional layers of clothing, or replace wet clothes with dry
- Get the person moving to increase their activity,
- Ensure the surroundings are as warm and still as possible
- Provide food, initially as hot liquids
- Add warmth with a fire or from body to body contact
There are things that a person should do for hypothermia and I have listed some of them below:
- Wrap them in blankets, towels, and coats, protecting the head first
- Remove any wet clothing and dry the person
- Move the person indoors or somewhere warm as soon as possible
- Increase activity if possible, but not to the point where sweating occurs, as that cools the skin down again
- Your own body heat can help them
- Give the person warms drinks but not alcohol
There are things that you should not to do when you have hypothermia and I have also listed some of them below:
- Don’t give the person any alcohol, as this will decrease the body’s ability to retain heat
- Don’t apply direct heat to the arms and legs, as this forces cold blood back to the major organs, making the conditions worse
- Don’t rub or massage the person’s skin, as this can cause the blood vessels to widen and decrease the body’s ability to retain heat
When to seek medical help?
If a person has been exposed to the cold and their distressed or confused, and they have slow, shallow breathing or their unconscious, they may have severe hypothermia and this means they have to seek medical help immediately as it could be life threatening. If you look at a person’s ski n that has hypothermia, it might look healthy, but they would feel cold and babies may also be limp, unusually quiet and refuse to feed.
As the body temperature drops, shivering will stop completely. The heart rate will slow and a person will gradually lose consciousness. They won't appear to have a pulse or be breathing. If possible, should be given while the person is being warmed. CPR is an emergency procedure that involves giving mouth-to-mouth resuscitation and chest compressions.
Modelling skin features and heat loss
Modelling is useful in science. Simple models can give us some initial insights into systems which are difficult to study. An example is the process of heat loss through our skin.
The structure of the skin is complex, but we can get a feel for the factors influencing the rate of heat loss through it using a simple model. This and other crude models can be a useful starting point for the design of more sophisticated experiments.
Equipments
Diagram
Method
- Put the boiling tube being investigated into a test tube rack.
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Pour 40cm3 of hot water (at a temperature about 70oC) into a 100cm3 measuring cylinder.
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Put a thermometer in the water and let it to cool to 60oC.
- Quickly pour the water into the boiling tube and put the thermometer into the water in the tube.
- Immediately record the temperature.
(Note: For Tube 4 measure 50cm3 of hot water. When it cools to 60oC, pour 10cm3 over the tissue to wet it thoroughly. Pour the remainder into the tube and continue as for the other tubes.
- Record the temperature of the water every minute for 10 minutes.
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Plot a graph of temperature in oC (y-axis) against time in minutes (x-axis).
- Plot the results for all four tubes on the same graph paper.
Risk Assessment
Results
Analysis
By looking at the table of the results, all the tubes have a decrease in temperature as the time in minute’s increases. This shows that the amount of heat have been lost as the time increases. I have done a graph to show my results, and by looking at the graph, tube 4 has the highest temperature for 0 minutes, then all the other tubes.
Conclusion
Test tube 1 has lost more heat than test tube 4 because test tube 1 didn’t have any layer of tissue, which in simple terms means nothing to protect or trap the air to keep it warm. The test tubes can be compared to the human body, as if you don’t wear layers on to trap the heat or air, then you will feel cold as there is nothing to protect you or make you warm. As you can see from the graph, the starting point of test tube 4 is 72oC and for test tube 1 is 69oC and this is has a small difference in temperature, but after 10 minutes, the temperature for test tube 4 is 65oC and the temperature for test tube 1 is 54o and this is a bigger difference of 11 C. This shows that test tube 1 have lost more heat than test tube 1 as there is no layer of tissue to protect test tube 1.
Evaluation
To evaluate this experiment, if I was to improve the investigation, then I would suggest that the experiment should be done more than once to get a reliable result. The four test tubes was recorded at different time intervals and this was time consuming as we was recording each test tube at different times and this shows that the experiment is not valid or reliable as the surrounding temperature may vary from time to time and as it was carried out at different times, the results that I have obtained might not be reliable. To improve this, I would have carried out the experiment on all four tubes at the same times so that I would a reliable result or I would have carried out the experiment by doing one test tube at a time so that I can get a better result for each test tube.
Furthermore, I would have carried out the experiment longer, so instead of 10 minutes, I would have carried it out for 15 minutes. This would have improved my investigation, as the longer you record the temperature for each test tube, the better the results would be. Also I would have found out which test tube has trapped more heat by carrying the experiment out longer.
Monitoring heat loss from the body
Normally your body is about 37oC. In the UK this is usually hotter than the air around it. The result is that heat flows from your body to the air. However, if the air is hotter than 37oC, heat will flow from the air to your body. The body, however, has mechanisms for maintaining a reasonably constant temperature. This is called homeostasis.
There are three ways that heat flows which are conduction, radiation and convection.
How can you minimise heat loss from your body by these three heat flows?
Conduction
Keeps contact with the ground and solid objects to a minimum e.g. stay on your feet. The ground is a better conductor than air. Keep your body insulated by wearing several layers of clothing (the trapped air is a good insulator).
Convection
It keeps out of the wind and air around you heats up by conduction from your body. It becomes less dense, rises and carries the heat away. It’s replaced by cool air and the process is repeated over and over. This is natural convection. When the wind blows it carries the heated air even more quickly. This is forced convection.
Radiation
Stand under a shelter and this will reflect heat.
Equipments
Method
- Attach a skin temperature probe to the back of one hand. Attach a second probe (the control) to the back of the other hand. Record the temperature at each position. It should be the same. If not check for possible causes and eliminate them.
- Record the volunteer’s core body temperature using a clinical thermometer.
- Ask the volunteer to sit with their hands palm down on a table, arms spread apart as far as possible, but comfortably so.
- Position a fan midway between the hands pointing at the non-control hand and away from the control hand. Arrange it so that it will blow air a few centimetres above the surface of the hand.
- Start recording the temperatures of the hand under investigation and the control hand. After five minutes turn on the fan and continue to record the two temperatures for a further five minutes.
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Plot on the same graph, temperature of cooled hand / oC (y-axis) against time / minutes (x-axis) and temperature of control hand / oC (y-axis) against time / minutes (x-axis).
Risk Assessment
Results
Analysis
As you can see above, I have the results of monitoring the heat loss in the body and the temperature. I have found out that the Normal hand temperature is 39.00C and this stays constant throughout because it is not getting affected by anything and it’s not losing any air because it’s a normal human temperature. On the other hand, wet/fan has a lot of heat because it was getting affected by the air and water in the surroundings, which made the temperature to decrease.
Conclusion
The table of results and the graph above shows the results of monitoring the heat loss in the body and temperature. I have found out that normal hand temperature stays the same or remain constant throughout because nothing is affecting the temperature, so it’s not losing air as it’s a human normal temperature. On the other hand, the left hand wet/fan temperature has lost a lot of heat because it was getting affected by the air in the surroundings and the water. This made a change in the results, as the temperature has decreased.
Evaluation
To evaluate this experiment, if I was to improve the investigation, then I would carried out the experiment longer, so instead of 5 minutes, I would have carried it out for 10 minutes or longer. This would have improved my investigation, as I would have obtained a reliable result. The longer you record the temperature, the better the results.
Another way I have improved my investigation is by increasing the number of volunteers that was part of the investigation. As we only used one volunteer to get the results, we wouldn’t have got a reliable result and in order to get a reliable result, I would increase the number of volunteers so that I can collect all the results and compare it. By comparing the set of results, I would get a reliable result and this would make a change to my experiment and I can find out which hand condition lost more heat.