What are the different types of thermometers?

Digital thermometers

Digital thermometers provide the fastest and most accurate results in taking temperature. Available in many shapes and sizes, they can be found at a variety of locations such as grocery stores and pharmacies. Be sure to read the instructions given to you with the thermometer so that you can get the most accurate results; this also goes for any other type of thermometer you may use. There is a sensor on the end of the thermometer that touches the body part and reads the body’s temperature.

digital thermometer

2 piece thermometer

You can use a digital thermometer in three ways:

  • Oral (in the mouth)
  • Rectal (in the bottom)
  • Axillary (under the arm)

Do not use the same thermometer for both oral and rectal readings.

Electronic ear thermometer

This thermometer measures the temperature inside of the ear by reading the infrared heat from inside of the ear. For best results make sure to follow the device’s directions on where inside the ear to place the thermometer. For older babies and children they can be quicker and easier to use. For babies 3 months or younger the results may not be as reliable. If the child has too much earwax, the results may not be accurate.

Ear thermometer

Forehead thermometers

Forehead thermometers are also used to measure temperature, but may not be as reliable as the digital thermometers. They are placed on the temporal artery of the forehead and reads the infrared heat that comes off of the head.

forehead thermometer

Plastic “fever” strip thermometers

Strip-type thermometers are not reliable measurements of body temperature. They indicate temperature of the skin only.

Glass and mercury thermometers

A mercury thermometer a glass tube with mercury inside of the tube. The tube goes underneath the tongue and the body temperature will cause the mercury to rise inside the tube. The point where the mercury stops is your temperature reading.

However, while mercury thermometers were once the popular way to take a temperature, they are no longer available. These thermometers are easily broken, increasing the risk of exposure to poisonous mercury and broken glass shards. If you still have mercury thermometers you are encouraged to dispose of them safely. Consult with your doctor or your local health department for the right way to dispose of the thermometer.

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