The AquaVent is calibrated against a range of set reference points to an accuracy of 3 decimal places. During the calibration procedure, the AquaVent logger is fully submerged in a highly accurate water bath. The bath is set and allowed to stabilize. The pressure is then calibrated to six separate pressure points covering the entire range of pressure for that particular AquaVent to check for any nonlinearity. The process is repeated again at two different temperatures to check for temperature effects. Once done, the AquaVent is approved after all specifications for accuracy, precision, stability and hysteresis have been met. The AquaVent should be calibrated for the life-time of the instrument, as long as it is used within its specified range.