I. A diagram showing the layout of a three-transducer ... dissolved in the fluid filling the system is acceptable (provided it remains in solution: it is normally impracticable to remove such air). ... The Middlesex Hospital, London WI, UK. necessary in routine clinical situations where sterility. speed. simplicity and ruggedness ... The rear of the transducer body is hermetically sealed except for port (K). which connects via calibration line (E) to vacuum gauge (C) and a three- way stop cock (A).