Can we “see” through dust and smoke with an infrared thermometer?

No, the infrared thermometers cannot see thru these interferences. However, in most industrial applications the dust and smoke are rising from the hot object and, if your eye was as fast as the IR thermometer you can see openings where the instrument has a clear line of sight. With the aid of a function called a peak picker the instrument can indicate the target temperature and ignore the cold readings caused by the dust and smoke.