Accuracy of Temporal Artery Thermometer

Temporal Artery Thermometer Accuracy: Facts & Insights

How accurate are temporal thermometers? Known for their forehead thermometer accuracy, temporal artery thermometers are considered to be very accurate in measuring body temperature..

They use infrared technology to measure the temperature of the temporal artery, which is located on the forehead. This method is considered to be non-invasive and is typically considered more comfortable for adults and children.


How Accurate are Temporal Artery Thermometers?

How it Works

The best place to measure temperature is the center of the heart, but this can be done only under a doctor's supervision. Doctors know that measurement of the blood temperature in a major artery accurately reflects true body temperature. The TemporalScanner Thermometer is designed to measure the temperature of the skin surface over the temporal artery, a major artery of the head.

The temporal artery is connected to the heart via the carotid artery, directly leading from the aorta, the main trunk of the arterial system. It offers constant blood flow. It is the only such artery positioned close enough to the skin surface to provide access needed to take an accurate measurement. It is easy to use because it is ideally located at the front portion of the forehead. 

Learn how to use temporal artery thermometers to best measure temperature and avoid inaccuracies.


What Can Cause Inaccuracies

Despite their accuracy, forehead thermometer accuracy can be affected by factors like age, skin condition, and environment temperature.

It is important to follow the instructions when using a temporal artery thermometer to ensure that it is used correctly, and also it should be calibrated as per the manufacturer's instructions to maintain its accuracy over time.

Dirty Lens

Dirt, greasy films, or moisture on the lens will interfere with the passage of infrared heat and affect the accuracy of the instrument. dirt, greasy films, or moisture on the lens will interfere with the passage of infrared heat and affect the accuracy of the instrument.

Improper Scanning

The user of the temporal artery thermometer is improperly scanning down the side of the face, instead of scanning straight across the forehead. 

Releasing the Button Early

Releasing the button of the Exergen thermometer before finishing the temperature measurement can cause an abnormally low reading. Instead, release the button after the measurement is finished.

Full List of Causes

Possible causes of abnormal readings of temporal thermometers.

Type of Abnormal Temperature Possible Cause Helpful Hint
Abnormally low temperature Dirty Lens Clean lens of scanner every two weeks.
Abnormally low temperature Releasing the button before finished measuring Release the button after finished measuring.
Abnormally low temperature Measuring when an ice pack or wet compress is on the forehead Remove the ice pack or wet compress, wait 2 minutes, and re-take temperature
Abnormally low temperature Measure a completely diaphoretic patient Complete diaphoresis includes diaphoresis of area behind the ear and suggests that the temperature is rapidly dropping. Use an alternative method of temperature measurement in these cases until the patient is dry and the temporal artery measurement can be repeated.
Abnormally low temperature "Improperly scanning down the

side of the face"

Scan straight across forehead. The temporal artery is closest to skin in that area.
Abnormally high-temperature Anything covering the area to be measured would insulate and prevent heat from dissipating, resulting in falsely high readings. Confirm that the measurement site has not recently been in contact with heat insulators such as hats, blankets, and hair. Scan the area not covered or wait about 30 seconds for the previously covered area to equilibrate to the environment.


What To Do If You Experience Inaccurate Temperature Readings

What should I do if I get an abnormally high or low reading? How do I confirm my reading? Here’s what you should do if you happen to get an inaccurate reading. 

  • Repeat the reading with the same Temporal Scanner; a correct reading will be reproducible. 
  • Repeat the reading with another Temporal Scanner, if there is one available. Two Temporal Scanners with the same reading will confirm the reading. 
  • Sequential readings on the same patient in rapid succession will cool the skin; it is best to wait about 30 seconds for the skin to recover from the cold probe. 

Clinical Studies on Accuracy

Peer-reviewed clinical studies  are the gold standard for assessing temporal thermometer accuracy, as they involve real-world use across various settings and account for physiological variations. Only these studies can provide the assurance that the thermometer will provide accuracy in detecting fevers for all ages in all settings.

With over 100 peer-reviewed studies confirming forehead thermometer accuracy across all ages and settings for fever detection, Exergen's thermometers are among the most clinically proven for precision compared to others lacking extensive studies.

View Highlights from Clinical Studies on Temporal Thermometer Accuracy

The TemporalScanner is easier and gentler to use than other types of temperature measurement devices, such as oral, rectal, underarm and in-ear thermometers, because it is truly non-invasive.

How to Get an Accurate Reading with a Temporal Artery Thermometer

To use the thermometer for accurate temperature readings, you must scan the temporal artery.

Slide the thermometer in a reasonably straight line across the forehead, midway between the eyebrows and the upper hairline. 

When using the temporal artery thermometer, do not slide down the side of the face. Midway on the forehead area, the temporal artery is less than 2 millimeters below the skin surface, down the side of the face. Be sure to choose the side of the head that is least exposed.

step 1

Remove the protective cap and place the thermometer head flat against the forehead.

scan the forehead

step 2

Once the thermometer is touching the skin, press the button and keep it depressed as you glide your Exergen scanner across the forehead at the hairline. Do not go down the side of the face or the technology can’t work.

step 3

While still holding the button down on the thermometer, use the scanner to touch the soft spot behind the ear. Then let go of the button and read the temperature.

Accuracy Vs Other Temperature Methods

Arterial temperature is the same temperature as the blood flowing from the heart. It is the best determinant of body temperature. The TemporalScanner is easier and gentler to use than other types of temperature measurement devices, such as oral, rectal, underarm and in-ear thermometers, because it is truly non-invasive.

The temporal arterial temperature method eliminates any discomfort that would be caused by a thermometer inserted into the ear, mouth, or rectum. 

Why Are Temporal Thermometers More Accurate than Infrared No-Touch Devices?

While temporal artery thermometers and non-contact thermometers are both used to measure body temperature, the latter is less accurate because it measures the temperature on the skin surface rather than the temperature of the body's core.

Why Are Temporal Thermometers More Accurate than Ear Thermometers?

A major reason ear thermometers are considered inaccurate by medical professionals is because the positioning of the probe in the ear canal is inconsistent, thus creating inconsistent readings and frequently missing fevers. The temporal artery thermometer scans the forehead area for the temporal artery and it is almost impossible to miss the artery during a scan.

Also, the person whose temperature is being taken does not like something inserted in their ear, making good positioning even more difficult. The gentle scan across the forehead is comfortable and not objectionable. The TemporalScanner thermometer has been proven more accurate than ear thermometers by a Harvard Medical School study.

Using Temporal Artery Thermometers

Temporal artery thermometers are considered to be the most accurate, non-invasive method in measuring body temperature. Learn more about Exergen forehead thermometer for home use models for adults and children.