When checking the calibration of an instrument, what is the first information to record?

The first information to record when checking the calibration of an instrument is the calibration data before adjustment. This step is crucial as it provides a baseline for comparison. By documenting the original calibration data, technicians can assess the instrument’s performance and determine if it is operating within the specified tolerance limits. This initial data serves as a reference point to observe how adjustments impact the instrument's accuracy and reliability.

Recording this information first ensures that there is a detailed account of the instrument's state prior to any modifications. If changes are made during calibration, having this baseline data allows for a thorough evaluation of the changes and confirms whether the adjustments brought the instrument back into compliance with its specifications. This process is essential for maintaining instruments' integrity and ensuring that any readings are trustworthy and reproducible.