Leak detector for endoscopes

A method for detecting the integrity of a device with an internal passage of unknown volume undergoing reprocessing in a reprocessing chamber, the device being one in which the internal passage undergoes a change in temperature during testing, the method comprising:

• (a) supplying a quantity of gas under pressure to the internal passage of the device and to an interior chamber, the quantity being dependent on the time taken to fill the internal passage to a selected pressure;
• (b) measuring the time taken to fill the internal passage to the selected pressure;
• (c) determining the quantity of gas in the internal passage from the time taken to fill the internal passage to the selected pressure;
• (d) sealing the interior chamber and the internal passage to fix the determined volume;
• (e) measuring a temperature and a pressure of the gas within the internal passage at a first time;
• (f) measuring the temperature and pressure of the gas within the internal passage at a second time;
• and
• (g) determining from the determined quantity of gas and a change in the measured temperatures and a change in the measured pressures of the gas at the first and second times whether leakage of the gas from the internal passage has occurred.

A method for testing the integrity of an endoscope device with an internal passage undergoing reprocessing in a reprocessing chamber, the reprocessing causing changes in temperature of the endoscope during the testing, the method comprising:

• (a) placing the endoscope in a reprocessing vessel and releasably connecting the endoscope to a leak detection system;
• (b) supplying a quantity of gas under pressure through a tubing section adjacent the releasable connection to the internal passage of the endoscope;
• (c) determining whether the pressure in the tubing section reaches a minimum preselected pressure, and if the tubing section does not reach the minimum pressure, examining the endoscope for damage;
• (d) measuring the time taken to fill the internal passage to a selected pressure;
• (e) determining the quantity of gas in the internal passage from the time taken to fill the internal passage to a selected pressure;
• (f) comparing the measured fill time with a preselected maximum fill time;
• (g) sealing the tubing section and the internal passage to define a closed volume;
• (h) measuring a temperature and a pressure of the gas within the tubing section closely adjacent the releasable connection at a first time;
• (i) measuring the temperature and pressure of gas within the tubing section at a second time;
• and
• (j) determining from a change in the measured temperatures and a change in the measured pressures of the gas within the tubing section at the first and second times whether leakage of the gas from the endoscope internal passage has occurred.

A method of leak testing an endoscope of undetermined internal lumen volume comprising:

• filling the endoscope lumen to a preselected above atmospheric pressure;
• determining a volume of gas used to fill the endoscope lumen to the preselected above atmospheric pressure;
• a measured time interval after filling the endoscope lumen, determining a volume of gas remaining in the endoscope lumen;
• from the determined fill volume, the determined remaining volume, and the measured time interval, determining a rate of change of the volume of gas in the endoscope lumen;
• from the rate of volume change, determining whether unacceptable leakage has occurred.

A method of detecting leaks in an endoscope having at least one lumen of unspecified volume, the method comprising:

• filling the endoscope lumen with test gas;
• determining a volume of the lumen from a quantity and pressure of the test gas used to fill the lumen;
• measuring a drop in pressure over time of the test gas in the lumen;
• from both the determined lumen volume and the pressure drop, determining whether leakage above a preselected level has occurred, such that dynamic compensation is made for the lumen volume.