Infuse 15 ml of endotoxin-free water into the lumen of medical device (e.g. infusion apparatus, dialysis tubing, etc.) and shocks five times, seal all the ends and incubate it at 37°C water bath for 2 hours, then transfer the water to an endotoxin-free vial. Detect the endotoxin concentration in the water by using ToxinSensor Chromogenic LAL Endotoxin Assay Kit(Cat. No. L00350), and the total endotoxin value in the water can be determined.