The calibration drift check reading of a water quality monitor sensor for pH, during a site visit. The Code indicating whether the reading is for calibration or recalibration. The date and time of the pH check or calibration reading. The theoretical value of the standard solution, in units of the parameter. The code identifying the type of the standard, KCl or NaCl. The lot number of the standard solution. The expiration date of the standard solution. Was this this reading for the conductance standard that was used for recalibration? The temperature during the pH sensor check or calibration,in degrees celsius. The pH read during the pH sensor check or calibration, in standard units. The slope of the pH sensor read during the pH sensor check or calibration. The voltage of the pH sensor read during the pH sensor check or calibration, in volts. The percent error between the pH buffer and the calibration reading.