a) establishes the free-field convergent spherical wave self-reciprocity method for ultrasonic transducer calibration,

b) establishes the measurement conditions and experimental procedure required to determine the transducer's electroacoustic parameters and acoustic output power using the self-reciprocity method,

c) establishes the criteria for checking the reciprocity of these transducers and the linear range of the focused field, and

d) provides guiding information for the assessment of the overall measurement uncertainties for radiation conductance.

i) circular spherically curved concave focusing transducers without a centric hole working in the linear amplitude range,

ii) measurements in the frequency range 0,5 MHz to 15 MHz, and

iii) acoustic pressure amplitudes in the focused field within the linear amplitude range.