User's Manual

Clarius Ultrasound Scanner - HD3 Scanners Safety Topics
revision 1 61
Separation Distance
Recommended Separation Distance
The following table shows recommended separation distances for the system to be kept away
from any RF-transmitting equipment. To reduce the risk of interference, when using portable
and mobile RF communications equipment, follow the recommended separation distance
(calculated from the equation applicable to the frequency of the transmitter). Ensure that field
strengths from fixed RF transmitters, as determined by an electromagnetic site survey, are less
than the compliance level in each frequency range as noted in the table.
Field strength is difficult to predict theoretically with accuracy if they come from fixed
transmitters, such as base stations for radio (cellular/cordless) telephones and land mobile
radios, amateur radio, AM and FM radio broadcast, and TV broadcast. To assess the
electromagnetic environment from fixed RF transmitters, consider conducting an
electromagnetic site survey. If the measured field strength in the location in which the system
is used exceeds the applicable RF compliance level in the table, observe the system to verify
normal operation. If abnormal performance is observed, apply additional measures, such as
reorienting or relocating the system.
The table here provides guidance on conducted and radiated interference from portable and
fixed RF transmitting equipment.
For example, if a portable transmitter has a maximum radiated power of 1 W and an operating
frequency of 156 MHz, it can be operated at distances greater than 1.2 m (3.9 ft) from the
system. Similarly, a 0.01 W Bluetooth wireless LAN smart device operating at 2.4 GHz should
be placed no closer than 0.24 m (9.5 in) from any part of the system.
At 80 MHz and 800 MHz, the higher frequency range applies.
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.
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 0.35 m (13.8 in) 0.12 m (4.7 in) 0.23 m (9.1 in)
0.1 1.1 m (3.6 ft) 0.38 m (15 in) 0.73 m (28.7 in)
1 3.5 m (11.5 ft) 1.2 m (3.9 ft) 2.3 m (7.5 ft)
10 11 m (36.1 ft) 3.8 m (12.5 ft) 7.3 m (24 ft)
100 35 m (114.8 ft) 12 m (39.4 ft) 23 m (75.5 ft)