How To Use A Temporal Artery Thermometer

Medically Reviewed by Carol DerSarkissian, MD on May 01, 2023
4 min read

Your temporal artery is a blood vessel that runs across the middle of your forehead. A temporal artery thermometer (TAT) is one that you place on the skin of your forehead to get a readout of your body temperature. It uses infrared technology to measure the heat energy your body gives off.

You would likely use this or another type of thermometer when you suspect that you or someone in your care has a fever. Temporal artery thermometers are especially quick to show results.

Besides body heat, signs that you may have a fever include:‌

  • Sweating‌
  • Chills or shivering‌
  • Headache‌
  • Muscle aches‌
  • Loss of appetite‌
  • Skin rash‌
  • Restlessness‌
  • Weakness

A body temperature of 100.4 degrees Fahrenheit or higher signals a fever. But body temperature is different for infants and adults. For an infant, this temperature is more of a concern than it may be for an adult. 

‌‌Your body temperature is naturally higher in the afternoon or evening. Eating and exercising may also have an impact on your temperature.

When you have a fever, it’s a sign that your body is fighting off an infection, and that’s a good thing. A fever means your body’s working to fight a virus or bacteria that somehow entered your system. 

Besides an infection, you may also have a fever because of:‌

  • Health conditions, such as rheumatoid arthritis, that cause inflammation‌
  • Reactions to drugs or vaccines‌
  • Some cancers 

And if your fever gets too high, it can cause:‌

  • Confusion‌
  • Extreme sleepiness‌
  • Irritability‌
  • Seizures 

1. Know your thermometer. Read the instructions for your particular thermometer. Be sure you know how to store and maintain it.‌

2. Turn the thermometer on. Ensure it is ready for use.‌

3. Place the sensor. Align the sensor with the middle of your forehead for the most accurate reading.‌

4. Move the thermometer. Maintaining contact with your skin, drag the thermometer up your forehead to your hairline. ‌

5. Read the temperature. The screen displays your temperature based on the reading. If you think the reading is inaccurate, try again. ‌‌

Your fever is generally considered safe up to 104 degrees Fahrenheit. If it goes over 104, you can try to lower it at home by:

  • Drinking water to cool your body off and prevent dehydration
  • Eating light meals that are easy for your body to digest
  • Resting and sleeping as much as you can
  • Taking ibuprofen, naproxen, acetaminophen, or aspirin to lower your temperature and improve your symptoms‌
  • Taking a lukewarm or cool bath

If you have a persistent fever that stays above 104 degrees Fahrenheit, call your doctor immediately. This is especially important if you develop any of the following symptoms:

  • Seizures
  • Loss of consciousness 
  • Feelings of confusion
  • Stiff neck
  • Difficulty breathing
  • Pain that is more severe than muscle aches
  • Swelling or inflammation in one particular area of your body‌
  • Vaginal discharge or urine that smells strong  

Pro. The main advantage of using a temporal artery thermometer is how quickly you can get a reading from it. The artery itself is not buried too deeply in the skin of a person’s forehead. As you scan it, the thermometer is taking hundreds of measurements per second of the heat the person’s body is giving off. 

Since there’s no wait for results and the devices do not cause discomfort, TATs are excellent for use on children.

Cons. You may find that a temporal artery thermometer costs more than other thermometer options because of its infrared technology. And you must be sure to remove conditions that could affect its accuracy. They include:

  • Direct sunlight
  • Lower surrounding temperatures
  • A sweaty forehead ‌
  • Lack of contact with the forehead 

You should also be ready to make one other adjustment. Especially because of COVID, researchers studied TATs along with more traditional thermometer types that involve more contact and read temperatures from other body parts:

  • Oral – a thermometer that goes under your tongue
  • Anal – a thermometer is inserted rectally and usually considered the most accurate 
  • Armpit – also called an axillary thermometer‌
  • Ear – also called a tympanic thermometer

Temperature readings vary by body part, but doctors generally agree on these:

  • Your oral temperature is considered normal around 98.6 degrees Fahrenheit.
  • Your rectal temperature is 0.5 to 1 degree Fahrenheit higher than your oral temperature.
  • Your tympanic temperature is 0.5 to 1 degree Fahrenheit higher than your oral temperature.
  • Your axillary temperature is usually 0.5 to 1 degree Fahrenheit lower than your oral temperature.‌
  • Your temporal temperature is usually 0.5 to 1 degree Fahrenheit lower than your oral temperature.

And doctors still consider rectal temperature to be the most accurate. 

So you may have to do a little math. For example, if you have a two-year-old and use a temporal artery thermometer, you may get a reading of 101 degrees Fahrenheit. The rectal or ear reading may be closer to 102 degrees Fahrenheit.

‌Always be sure to share what type of thermometer you used, as well as the reading, when you talk to a doctor about a fever.