What do I need to do if the food probe thermometer reading is off by more than 1 degree?

Date modified: 1st June 2025 | This FAQ page has been written by Pilla Founder, Liam Jones, click to email Liam directly, he reads every email. Or book a demo to see how hospitality businesses use Pilla to manage food safety.
Hospitality industry guidance and best practices

If your probe thermometer shows a reading that's off by more than 1 degree during calibration testing, you'll need to take these steps:

1. First, have your head chef verify the reading to confirm the deviation

2. If confirmed to be outside the 1-degree tolerance, record this in your Pilla task.

3. Remove the probe from service immediately

4. Replace it with a backup probe thermometer

5. Send the faulty probe back to the manufacturer for repair or replacement

Common misunderstanding: Once a food probe thermometer is calibrated, it doesn't need to be checked regularly.

This is incorrect. Regular calibration checks are crucial as probe thermometers can drift over time due to regular use and environmental factors. Industry best practices recommend checking calibration at least once a month or whenever you suspect inaccuracy, to ensure food safety standards are consistently met.

Common misunderstanding: You can rely solely on the digital readout of a thermometer without verifying it against physical calibration methods.

Digital readouts can sometimes be misleading if the device is malfunctioning or has been subjected to extreme conditions. It's essential to verify the accuracy using physical calibration methods, like the boiling water and ice bath tests, to ensure reliability.

How do I know if the reading is actually off by more than 1 degree?

You'll need to test the probe using both hot and cold calibration methods. For hot testing, the probe should read 100°C in boiling water (with 1 degree tolerance either way). For cold testing, use an ice bath which should read 0°C (again with 1 degree tolerance). If either test shows a greater deviation, that's when you need to take action.

Common misunderstanding: Ice water and boiling water tests are outdated and unnecessary for modern digital thermometers.

Despite technological advancements, the ice water and boiling water tests remain the most reliable and straightforward methods for checking thermometer accuracy. These tests provide a consistent baseline that digital displays alone cannot guarantee, ensuring precise readings essential for food safety.

Common misunderstanding: A deviation of more than 1 degree is insignificant in commercial kitchen settings.

Even a small deviation can significantly impact food safety, especially when dealing with perishable items and high-risk foods. Maintaining a strict 1-degree tolerance ensures that food is cooked or stored at safe temperatures, preventing potential health hazards.

Can I still use the probe if it's only slightly more than 1 degree off?

No, you should never use a probe that's reading outside the 1-degree tolerance range. Even a small inaccuracy could mean the difference between safe and unsafe food temperatures. This is a critical control point in your food safety system, so it's essential to use only properly calibrated probes. Always take it out of service and get a replacement.

Common misunderstanding: A slight inaccuracy in probe readings is acceptable as long as the chef is experienced and can compensate for it.

Relying on experience to compensate for inaccurate readings is risky. Precise temperature measurement is critical for food safety, and human judgment cannot replace the accuracy of a properly calibrated thermometer. Using a probe that reads accurately within the specified tolerance is essential to ensure all food is safe for consumption.

Common misunderstanding: Once a probe is slightly off, it will naturally recalibrate itself over time with regular use.

Thermometers do not self-correct. If a probe is reading inaccurately, it will remain so without proper recalibration or repair. Continued use of an inaccurate thermometer can lead to unsafe food handling practices, emphasizing the need for timely calibration and maintenance.

UK Official Guidance

USA Official Guidance