When and How to use infrared thermometer?

Posted by HoldPeak on 6th Nov 2020

IR Infrared Thermometer Handhold -50-800℃

Infrared thermometer offer speed and convenience, but what applications are best suited to infrared thermometer, and how can you be sure the readings are accurate? Our laser-focused tips will help you understand how infrared temperatures are measured so you can be confident in the accuracy of your readings.



Infrared thermometers are ideal for taking temperatures need to be tested from a distance. They provide accurate temperatures without ever having to touch the object you’re measuring (and even if your subject is in motion).

This is ideal when you can’t insert a probe into the item being measured, if the surface is out of reach, or if you have to keep your distance because of high heat. You might use an infrared thermometer to measure objects that are:

Fragile (computer circuitry)
Dangerous (gears, molten metal)
Impenetrable (frozen foods)
Susceptible to contamination (foods, saline solution)
Moving (conveyor belt, living organisms)
Out of reach (air conditioning ducts, ear drums)

HP-985B Digital Infrared Thermometer Dual Laser Thermometer


Infrared thermometers are great for checking surface temperature, however, they do not measure the internal temperature of an object.

Infrared thermometers are very fast, typically giving a reading in a fraction of a second, or the time it takes for the thermometer’s processor to perform its calculations. Their speed and relative ease of use have made infrared thermometers invaluable public safety tools in the food service industry, manufacturing, HVAC, asphalt & concrete, labs and countless other industrial applications.


Infrared thermometers can be very useful when used in the right way and put to task in the right applications. However, before you can develop confidence in their ability to give fast temperatures, you need to understand their limitations.

Infrared thermometers:

  • Only measure surface temperatures and NOT the internal temperature of food or other materials. An IR thermometer is not a substitute when an instant-read thermometer is needed to measure internal temperatures in foods.
  • Require adjustments depending on the surface being measured (See “What is emissivity” below)
  • Are not thought to be as highly accurate as surface probes measurements of the same *surface
  • Can be temporarily affected by frost, moisture, dust, fog, smoke or other particles in the air
  • Can be temporarily affected by rapid changes in ambient temperature
  • Can be temporarily affected by proximity to a radio frequency with an electromagnetic field strength of three volts per meter or greater
  • Do not “see through” glass, liquids or other transparent surfaces—even though visible light (like a laser) passes through them (i.e. if you point an IR gun at a window, you’ll be measuring the temperature of the window pane, not the outside temp).

* In some cases, Infrared Thermometers can be MORE accurate than a surface probe because surface probes have their own temperature and can affect the surface being measured by coming into contact with it.