Patent ID: 7875126

Claim:
A method of supplying a gas through a nozzle to a fitting attached to an opening of a duct provided in an endoscope to sense a water leakage of the endoscope, comprising the steps of: starting the supply of the gas through the nozzle under a condition in which the nozzle is not coupled to the opening, the gas being supplied at a first pressure in order to remove and prevent liquid drops from forming inside the endoscope; moving the nozzle toward the opening after the start of the supply of the gas; inserting the nozzle into the opening until the nozzle is coupled to the opening; supplying the gas at a second pressure to sense a water leakage from inside of the endoscope after the nozzle is coupled to the opening and determining whether or not there is a water leakage based on the pressure inside of the endoscope; wherein the first pressure is greater than the second pressure.