Quality control protocols and methods for determining replacement and proper location for listening to body fluids

A method for performing a quality control process on a sensor comprising performing the following steps in order:

• b. placing a sensor adjacent to a skin surface of a patient, said sensor comprising a piezoelectric element for detecting sound waves generated under said skin surface;
• c. detecting said sound waves with said sensor;
• d. comparing said detected sound waves to a predetermined sound fingerprint corresponding to the area of skin surface being tested;
• e. determining whether said piezoelectric element is functioning wherein proper functioning is determined when said detected sound waves are within a predetermined tolerance of said sound fingerprint;
• f. adjusting the sensor's position if the detected sound waves are outside of a predetermined tolerance and reperforming the test at a new position;
• and
• g. wherein said detected sound waves are outside of the predetermined tolerance at the new position, replacing said piezoelectric element if said detected waves are outside of said predetermined tolerance;
• and
• h. proceeding to take a data sample from said patient upon confirmation that the piezoelectric element is detecting said sound waves within said predetermined tolerance.