What must be done to ensure a thermometer is accurate?

To ensure a thermometer is accurate, regular cleaning and calibration are essential. This practice helps maintain accuracy over time and ensures that the thermometer is providing correct temperature readings. Cleaning the thermometer after each use helps prevent cross-contamination and ensures any residue from previous measurements does not affect future readings. Calibration, which involves adjusting the thermometer to align with the true temperature, is crucial because environmental factors or wear can lead to inaccuracies. Regularly performing these tasks is a fundamental part of food safety protocols, which help in maintaining safe food handling practices and ensuring the health of customers.

The other options, such as checking it once a year, only using it in one type of food, or storing it in a cold environment, do not adequately address the requirement for ongoing accuracy and reliability needed in food service operations. Regular checks and a broader application across different food types are also important in a comprehensive food safety management system.