A minimum/maximum thermometer is essential for temperature monitoring of vaccine fridges and vaccine cooler boxes. Purpose built vaccine fridges incorporate their own minimum/maximum thermometers, but bar fridges and most coolers do not.

The portable min/max thermometer allows for the recording of temperatures in whatever position the probe is located. The probe should be taped inside an empty vaccine box. Min/Max thermometers will need to be reset regularly (i.e. at least daily on work days). Minimum/maximum digital thermometers must have an accuracy of at least ±1^oC.