Body temperature and thermometers
Readings using different types of thermometers will be the same but different readings will be obtained from different parts of the body.
Body temperatures are a result of our bodies producing, maintaining and dissipating heat. When our body heats up, the blood capillaries under our skin will expand resulting in an increase in blood flow - this allows more heat to be carried from within our body to the surface of our skin. This is where the heat is released/dissipates - resulting an reduction of the body temperature. In cold climates, the blood vessels contract restricting the flow of blood to the skin surface, allowing for increased heat retention.
A normal body temperature is about 37 °C and this temperature may vary by about 0.6 °C depending on the time of the day. The temperature measured at our body cavities (eg. inside the ear or rectum) is normally up to 0.6 °C higher than oral temperature reading. Temperatures taken at the armpit or the skin, will be up to 0.6 °C lower than the oral temperature reading. Therefore different parts of the body will give different temperature readings.
Temperatures are taken from inside the mouth and under our armpits with a mercury or digital thermometer. Temperatures at the forehead are normally measured using a plastic thermal strip. The temperature is measured at the tympanic membrane inside the ear using an infrared thermometer.
Be extremely careful with glass mercury thermometers to avoid breakage/spillage of the mercury, which can be extremely toxic/dangerous. Adult assistance is required.