The No-Nonsense How-to Guide for Infrared Thermometers

How to use an infrared thermometer properly

• Measure solid surfaces: Use an intermediary object like a cast iron frying pan when measuring objects equipped with grills or have holes (e.g. outdoor barbecues and HVACs)
• Be aware of your measuring distance: The range of an infrared thermometer is limited by its distance-to-spot ratio. For example, a device with a 12:1 distance-to-spot ratio can measure a 1-inch area from a distance of 12 inches. However, at a distance of 12 feet, this area will grow to 1 foot. As such, this will reduce the precision of the test area.
• Adjust emissivity for better results: Different objects have different surface textures that emit different levels of thermal radiation. A good thermal thermometer will allow users to adjust this ‘emissivity‘ setting in a range of 0.1-1.0.
• Use a non-reflective surface: Problematic test subjects with high reflectivity can be measured by placing a piece of non-reflective tape on their surfaces. After allowing it to acclimatize by waiting half an hour, use the infrared thermometer to measure the piece of tape.
• Everything in equilibrium: An important thing to keep in mind is that the temperature gun needs to be at the same relative temperature as the object it is testing. If changing environments with different temperatures, give time for the IR thermometer to adjust to its present surroundings before use.
• Affected by air particles: Even though the infrared temperature monitor is a non-contact device, tiny microscopic air particles may get in the way between it and the test subject. Take precautions when measuring in an environment with heavy dust, fog, air pollution, or similar phenomenon.