How to measure body temperature accurately

In every family's medicine cabinet, especially families with young children, a thermometer is a necessary item and should be available to take care of the health of each member. When there are symptoms of fever or other diseases, especially when the Corona virus is developing rapidly, determining body temperature is very important. So what types of thermometers are there and how to use them effectively?

1. Measure temperature with a mercury thermometer

Mercury thermometers, also known as mercury thermometers, are familiar thermometers and are widely used not only in homes but also in medical facilities. The mercury thermometer was invented in 1714 by physicist Daniel Gabriel Fahrenheit (Amsterdam).

This is a type of thermometer used to measure body temperature, inside it contains mercury - a substance that can expand when the temperature increases. Therefore, a mercury thermometer cannot be used to measure temperatures below -39oC (because it makes the mercury solid) or above 356.7oC (because this is the boiling point of mercury).

When using a mercury thermometer, we can choose to measure at many different positions on the body. Before measuring, gently shake the mercury line below the red triangle marked on the thermometer.

Measure body temperature in the armpit

Hold the thermometer in the armpit, pressing the elbow against the chest for about 4-5 minutes. For children, body temperature measured between 34.7 degrees - 37.3 degrees, the children do not have a fever. The same is true for adults. Usually, adults will use the method of measuring temperature in the armpit.

How to measure body temperature accurately

Oral temperature measurement

Note: Do not take the temperature within 30 minutes of eating or drinking hot food. Before measuring, wash with soap, place the tip of the thermometer under the tongue, hold the thermometer with your lips, and keep your lips closed around the thermometer. With a mercury thermometer, hold it for about 3 minutes and with an electronic thermometer, hold it for less than 1 minute.

If a child's temperature is between 35.5 and 37.5 degrees, they do not have a fever. For adults, an oral temperature greater than 37.5 degrees Celsius is a sign of fever.

Rectal temperature measurement

The method of measuring body temperature in the rectum will give absolutely accurate results. Soak the thermometer tip with lubricant and then gently insert the thermometer bulb about 2 - 2.5 cm deep into the rectum. Hold for 3 minutes then take it out to read the result. When the temperature in the rectum of a child is 38 degrees Celsius or higher, there is a sign of fever, and in adults it is greater than 37.6 degrees Celsius.

2. Electronic thermometer

Electronic thermometers operate based on thermal sensors in areas in contact with the thermometer tip. Electronic thermometers are used to measure in the armpit, mouth or anus, displaying parameters electronically with LED lights that are easier to read than mercury thermometers and have an audible alarm when finished. Electronic thermometers measure body temperature using infrared rays, the contact time to get results is less than 30 seconds, higher safety.

How to measure body temperature accurately

3. Infrared thermometer

Infrared thermometer to measure temperature in the ear or forehead. This method is the fastest, taking no more than 3 seconds, very convenient, easy to measure. When measuring the temperature at the forehead, you need to place the thermometer in the middle and close to the forehead, scan from the middle of the forehead to the temple, about 1 - 3 cm and wait within 60 seconds to get the result. In case the temperature measured in the ear is greater than 38.1 degrees Celsius, it is a fever.

>>> Learn more: Which type of forehead thermometer is good?

How to measure body temperature accurately

If measuring through the ear, we need to pull the patient's ear back and press the measuring button. After about 1 - 3 seconds, we can remove the thermometer to see the result. When the temperature in the ear is 38 degrees Celsius or higher, it means a fever. This method is only for children over 6 months old. If the child's ear has a lot of earwax, the result will be inaccurate.

>>> You may be interested in: Which type of infrared thermometer is good?

How to measure body temperature accurately

Note that when young children show signs of fever, families need to monitor them regularly to quickly take them to a medical facility to avoid high fever leading to convulsions.

Hope this article is helpful to you!

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