There is a lot of posting about this. Do a search.
First, you should only use the readings as comparisons. With use, you will learn what temps things are supposed to be.
Second, IR thermo’s can not measure air or other gasses. They can measure the objects that are in contact with the gas.
Third, IR’s measure different on different types of surfaces (shiny reflective vs. flat black).
Say you use your IR Thermo in an electrical panel. Take the ambient temp of the panel, then get the average breaker temp, then look for high temp differential between breakers.
When you find heat, you can identify where it is coming from by “searching”. You can get five readings on one breaker at different locations on the breaker. You can tell if the heat is coming at the wire connection, at the panel connection at the back of the breaker or tell if the whole breaker is hot from high amperage passing through the breaker.
It is a tool with limitations, but allows you to take readings where you could not, with a contact thermometer.