User Manual

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Mechanical index is used to represent the mechanical effect (cavitation) the possibility of.MI
depends on the attenuation of peak pressure and the center frequency, the actual peak negative
pressure by the actual attenuation effect, which is caused by the actual attenuation between the
probe and the focus of the organization. The organization of all animal solid attenuation is higher
than 0.3 dB/cm/MHz, the peak value is lower than the actual value of negativepressurethat
change will change with the scan position.
Based on the above reasons, TI and MI display value is used to help the operator to implement
ALARA principle in ultrasonic inspection process.
9.8 Uncertainty of measurement
I
spta
31.2%
I
sppa
30.4%
center frequency (f
c
)
2%
Total power (W) 30.1%（5.6% Scan mode and combination mode）
Peak negative pressure(pr) 15.5%
9.9 Reference literature for sound
power and its safety
(1) “Bio-effects and Safety of Diagnostic Ultrasound” issued by AIUM in 1993
(2) “Medical Ultrasound Safety” issued by AIUM in 1994
(3) "Acoustic Output Measurement Standard for Diagnostic Ultrasound Equipment,
Revision 3" issued by AIUM/NEMA in 2004
(4) "Standard for real-time display of thermal and mechanical acoustic output indices on
diagnostic ultrasound equipment, Revision 2" issued by AIUM/NEMA in 2004
(5) "Information for Manufacturers Seeking Marketing Clearance of Diagnostic
Ultrasound Systems and Transducers" issued by FDA in 2008.
(6) “Medical electrical equipment - Part 2-37: Particular requirements for the basic safety
and essential performance of ultrasonic medical diagnostic and monitoring equipment”
issued by IEC in 2007.
9.10 Transducer surface temperature
EN60601-2-37:2008 according to the requirements of clause 201.11, the transducer surface