This article explains how to use a thermometer to check body temperature.
It provides step-by-step instructions for how to use each throw in of thermometer.
It also explains how to clean thermometers and how to interpret the results.
Verywell / Kelly Miller
Types of Thermometers
Body temperature can be measured in a few different ways.
*Discard old rectal thermometer and buy a new one for oral use.
Body temperature varies by location.
Most thermometers can be disinfected by wiping it with rubbing alcohol or an alcohol swab.
How to Use a Non-Contact Thermometer
Non-contact thermometers use infrared technology to measure skin temperature.
Each equipment works slightly differently, so be sure to read the package instructions.
Are Wrist Temperatures Accurate?
Wrist temperatures taken with non-contact remote infrared thermometers are fairly accurate.
Wrist temperatures measured by a smartwatch, however, may not be accurate.
This emerging technology shows promise but has yet to be scientifically validated.
How to Take an Oral Temperature
Oral thermometers are commonly recommended for adults.
However, they are not the best option for younger children.
Children are usually able to do this around age 4.
Instead, wait 20 to 30 minutes before taking temperature by mouth.
How to Take an Armpit Temperature
Armpitor axillarytemperature is typically measured with a multiuse digital thermometer.
Despite being the least accurate method, schools and daycares often prefer taking axillary temperatures to avoid spreading germs.
To use an axillary thermometer:
What Armpit Temperature Is a Fever?
Rectal temperatures are taken with a digital multiuse thermometer or manual mercury thermometer.
(Be sure to clearly label it for rectal use only.)
These thermometers are fast and easy to use but may read too low at times.
Different varieties of temporal thermometers are available.
In its earliest form, forehead thermometers measured temperature through skin contact.
Each model has different instructions for use.
Be sure to consult the package instructions.
They pose a danger if they break and release mercury, which is toxic.
Interestingly, what’s average appears to have dropped over time.
Certain temperatures or symptoms do warrant medical attention, though.
A fever of 107.6 F can cause brain damage and is a life-threatening emergency.
Seek emergency medical care for a fever of 105 F that does not quickly respond to treatment.
The right thermometer to use depends on age.
Most people can get a fairly accurate reading using a quality non-contact infrared thermometer.
Contactless thermometers can read temperatures at the temple, forehead, or wrist.
If you are unsure if the reading is accurate, try a different thermometer.
Frequently Asked Questions
Yes.
Contactless forehead thermometers are a good choice for screening for COVID.
Researchers have studied whether mothers could accurately determine if a child has a fever by touching them.
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