What should be done before using a pH meter?

Using a pH meter is essential for accurate water quality testing, and calibrating it every day ensures that the measurements remain precise and reliable. pH meters are sensitive instruments that can be affected by changes in temperature, ionic strength, and other factors in the environment. Regular calibration helps compensate for these variables and adjusts for any potential drift in readings over time.

Calibration involves using standard buffer solutions that provide known pH values, allowing the meter to adjust its readings to maintain accuracy. While some may choose to calibrate less frequently based on usage or conditions, daily calibration is the best practice, particularly in professional or critical applications, as it guarantees more consistent results in diverse conditions.

Cleaning the meter with distilled water, while important, is secondary to calibration as it primarily prevents contamination. Storing the meter correctly is also essential but does not directly affect the calibration process or the immediate preparation for an accurate reading. Therefore, calibrating every day stands out as the most critical step before using a pH meter.