Philips epiq 7, User Manual

Page: 80 / 318

NOTE
The recommended separation distance guidelines in the following table may not apply to all
situations. Electromagnetic propagation is affected by absorption and reflection from
structures, objects, and people.
The information provided here, in conjunction with “Electromagnetic Interference” on page 77 ,
provides guidance on conducted and radiated interference from portable and fixed RF
transmitting equipment.
Recommended Separation Distances by Transmitter Frequency
Rated Maximum Output
Power of Transmitter (Watts) 150 kHz to 80 MHz 80 to 800 MHz 800 MHz to 2.5 GHz
0.01 117 m (384 ft) 0.12 m (4.7 in) 0.24 m (9.5 in)
0.1 369 m (1210 ft) 0.38 m (15 in) 0.76 m (30 in)
1 1170 m (3840 ft) 1.2 m (3.9 ft) 2.4 m (7.9 ft)
10 3690 m (12100 ft) 3.8 m (12.5 ft) 7.6 m (25 ft)
100 11700 m (34800 ft) 12 m (39.4 ft) 24 m (78.7 ft)
The conducted RF test level is 3 V, and the system has a compliance level of 3 mV. For the
system, this means that the imaging system is extremely sensitive to RF interference in the
transducer passband. For example, for a 5-MHz imaging transducer, the frequency range of
interference from a 3-V/m field may be from 2 to 10 MHz and manifest itself as described in
“Electromagnetic Interference” on page 77 .
The 0.3 mV level is where the interference becomes acceptable to some clinical specialists.
Sensitivity to interference is dependent on operating mode and imaging control settings. The
order of increasing sensitivity to interference as a function of operating mode is 2D mode, 3D
mode, M-mode, Color mode, PW Doppler mode, and CW Doppler mode. The system is more
sensitive to interference in the CW Doppler or PW Doppler operating modes, but the
Safety Electromagnetic Compatibility
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