The 12237 has a temperature-buffered sensor enclosed in a bottle of propylene glycol solution, which ensures accurate measurements that are not impacted by rapid temperature fluctuations caused by frequent refrigerator or freezer door openings. The propylene glycol solution is GRAS (generally recognized as safe) and mimics temperature readings in a medium similar to common fluids stored in food and laboratory refrigerators, freezers and cold display cases.
The 12237 Certified Alarm Thermometer comes with a Min/Max memory, a large, easy-to-read LCD, and high/low alarm settings. The thermometer monitors temperature inside freezers, refrigerators, or cold holding display cases. The sensor has a 3 meter cable and a stainless steel, blunt probe enclosed in a sealed plastic bottle of propylene glycol. This enclosure prevents false alarms because the measurements of the probe are not impacted by rapid temperature fluctuations caused by frequent door openings that occur during normal use.
This digital thermometer mimics temperature readings in a medium similar to the common fluids stored in refrigerators and freezers in pharmacies and labs.
For more information check:
https://www.qainstruments.co.nz/products/certified-alarm-thermometer