PH MEASUREMENT TECHNOLOGY

PROBLEM TO BE SOLVED: To reduce the amount of waste liquid in the case of measuring the property of test liquid.SOLUTION: A method of one example includes: swinging at least a portion of a measuring tool for measuring the quality of a test liquid with the portion soaked in the test liquid to agitate the test liquid, and measuring the measuring tool after that; and making at least the portion of the measuring tool go through a hole provide in a lid of a waste liquid container, and spraying a cleaning fluid and drying air in succession under the lid while swinging the portion in the axial direction thereof. An embodiment includes a device for entirely or partially mounting the method.