Is calibration of a mercury-in-glass thermometer necessary when the thermometer is used to measure the temperature of a standard refrigerator that holds a tube of adhesive?
What is the range of storage temperature of that adhesive ?
If it is anything like 0'C to 8'C (cold room) which a standard commercial refrigerator maintains outside freezer box and inside the refrigerator compartment, and if the Hg in glass thermometer has a graduation for say, 0.5'C and can sense from 0'C to 25'C, I would not calibrate it after first time and store the thermometer safely when not in use.
I would be more interested to know if the refrigerator is assured kept powered on and working round the clock 24 x 7.
This measurement using the Hg in glass thermometer only gives temperatures at that measuring instant. A record of this temperature is no guarantee that the tube of adhesive has been stored all along at my measured temperatures.