Page 119 - Sterilization Training Manual

DIR INSTALLATION TIPS
Ò Chamber Leaks
Room air leaking (tiny leaks) into the chamber will make a pressure rise calculated density appear higher than it actually is. The DIR will appear to be reading low since there is little or no response to room air.
Ò H2O Channel Zero
Water is typically difficult to remove from the chamber. If there is pressure in the chamber following an evacuation, much of the remaining pressure can be due to water still present in the chamber. This would not be a good time to zero the H2O channel. Exposing the DIR to dry N2 directly or running several N2 chamber washes is usually required to dry the DIR enough for a good H2O zero.