The purpose of this article is to review the subject of IR Thermometers and the Emissivity setting.
You need to be aware of the surface emissivity parameters when using an IR thermometer.
To give an example the emissivity surface of copper is below the default setting of an IR thermometer setting of 0.98.
You can change the emissivity setting but first you need to use an Emissivity Chart to get you in the ballpark. Some of the IR thermometers will have emissivity charts in the manual but you can find Emissivity Charts online if the manual doesn’t have a chart or the chart doesn’t show the item you need.
Still using copper the charts states polished copper as 0.05 and copper oxidized 0.65. Once the emissivity gets below 0.60 you should isolate the surface from surrounding items. Example if the copper surface is polished and it was next to an oven the surface of the copper can reflect the IR energy and the IR thermometer can read that level. You would have to shield the surface of the copper from outside influence to get accurate measurements.
Another way around the emissivity levels being too low is to either paint the surface or put tape on it so you can get an accurate measurement without changing the emissivity (both tape and paint emissivity are 0.95).
If you have any further question call tech support at 1-800-873-5853.