Apparatus and method for detecting moisture in a vacuum chamber
A method of operating a sterilization system having a vacuum chamber for sterilizing instruments, the chamber connected to a reservoir of sterilant by a valve in a closed state, is disclosed. The method may include taking a baseline humidity measurement while the pressure within the chamber is a first pressure, lowering the pressure within the chamber to a conditioning pressure, maintaining the conditioning pressure for a dwell time, increasing the pressure within the chamber, acquiring a second humidity measurement from within the chamber, and comparing the baseline humidity measurement to the second humidity measurement.
1. A method of operating a sterilization system having a vacuum chamber for sterilizing instruments, comprising:
(a) acquiring a baseline humidity measurement from within the chamber;
(b) acquiring subsequent humidity measurements from within the chamber;
(c) withdrawing a first volume of air from the chamber;
(d) waiting for a dwell time after the first volume of air is withdrawn from the chamber;
(e) introducing a second volume of air into the chamber after waiting for the dwell time;
(f) identifying a maximum humidity measurement from among the subsequent humidity measurements; and
(g) comparing the maximum humidity measurement to another humidity measurement.
2. The method of claim 1 , wherein the another humidity measurement is the baseline humidity measurement.
3. The method of claim 2 , wherein the step of acquiring the subsequent humidity measurements includes repeatedly taking humidity measurement data with a humidity sensor and storing the data in a non-transitory storage medium of a digital computer.
4. The method of claim 3 , wherein the maximum humidity measurement is greater than the baseline humidity measurement.
5. The method of claim 4 , further comprising commencing a sequence of vacuum pulsing.
6. The method of claim 3 , wherein the maximum humidity measurement is less than or equal to the baseline humidity measurement.
7. The method of claim 6 , further comprising introducing a sterilant into the chamber.
8. The method of claim 7 , wherein the sterilant is hydrogen peroxide.
9. The method of claim 1 , wherein the step of withdrawing a first volume of air from the chamber is performed until a first pressure within the chamber equals a conditioning pressure.
10. The method of claim 9 , wherein the conditioning pressure is between approximately 5 torr and 15 torr.
11. The method of claim 10 , wherein the conditioning pressure is approximately 10 torr.
12. The method of claim 1 , wherein the dwell time is between approximately one second and approximately one minute.
13. The method of claim 12 , wherein the dwell time is approximately five seconds.
14. The method of claim 1 , further comprising identifying a minimum humidity measurement from among the subsequent humidity measurements.
15. The method of claim 14 , wherein the another humidity measurement is the minimum humidity measurement.
16. The method of claim 15 , further comprising determining that the maximum humidity measurement is approximately twice as large as the minimum humidity measurement.
17. The method of claim 16 , further comprising commencing a sequence of vacuum pulsing.