Measurement 9-5 
9.4  Measurement Accuracy 
Table 1 Error of 2D Images 
Parameter    Value Range  Error 
Distance  Full screen 
Within ±3%; or when the measured value is 
less than 40 mm, the error is less than1.5 mm.
Area (Trace)  Full screen 
Within ±7%; or when the measured value is 
less than 16 cm
2
, the error is less than 1.2 cm
2
.
Area (ellipse, 
circle) 
Full screen 
Within ±7%; or when the measured value is 
less than 16 cm
2
, the error is less than 1.2 cm
2
.
Angle  Full screen  Within ±3%. 
 
Table 2 Volume Measurements 
Parameter 
Value 
Range 
Error 
Volume    Full screen
Within ±10 %; or when the measured value is less than 64 cm
3
, 
the error is less than 6.4 cm
3
. 
 
Table 3 Time/Motion Measurements 
Parameter    Value Range  Error   
Distance    Full screen 
Within ±3 %; or when the measured value is 
less than 40mm, the error is less than 1.5mm. 
Time    Timeline Display  Within ±2%. 
Heart rate  Timeline Display  Within ±4%. 
 
Table 4 Doppler Velocity Measurements 
Parameter    Value Range  Error 
Velocity (PW mode)  Maximum ≥2.5m/s  When angle≤60º, ≤5%. 
Velocity (CW mode)  Maximum ≥2.5m/s  When angle≤60º, ≤5%. 
The above measurements are not applicable for the pencil probe (CW2s). 
 
NOTE:
Within the selected field range, the measurement accuracy is ensured within the 
range mentioned above. The accuracy specifications are performance in the 
worst conditions, or based on the real test for the system, regardless of acoustic 
speed error.