Temperature Variation With Different Thermometers

[Mary**]

After reading about using infrared thermometers on this site to take the temperature of units issued in igloos, I purchased one of these. We had been using Temp Chek. I validated both thermometers with a NIST thermometer.

Taking the temperature of the same unit, I got -0.6C with the infrared and 5C with the Temp Chek. I wonder if I am using the infrared incorrectly. I don't know which to believe.

I would appreciate any advise. :confused:

[JEMarti]

IR thermometers can give you varying results depending upon where on the bag you aim them. The label can have a significant effect. IR passes through rbc's rather efficiently so aiming toward the edge where the thickness of the bag can also contribute to variability of readings. Your best bet is to validate temp readings to a region of the bag that gives you reliable results.