21
Recommended protective distances between
portable and mobile HF telecommunication devices and the [DEVICE or SYSTEM]
Model MD 10544 is intended for operation in an electromagnetic environment in which the HF interference is controlled
. The customer or user of Model MD 10544 can help to avoid electromagnetic interference
by adhering to the minimum distance between portable and mobile HF telecommunication devices (transmitters) and the
Model MD 10544 – depending on the output of the communication device as shown below.
Protective distance depending on the transmission frequency
m
Nominal output
of transmitter
W
150 kHz to 80 MHz
outside the
ISM bands
150 kHz to 80 MHz
within the
ISM bands
80 MHz to
800 MHz
d = 1.2
800 MHz to
2.5 GHz
d = 2.3
0.01 N/A
N/A
0.12 0.23
0.1 N/A
N/A
0.38 0.73
1 N/A
N/A
1.2 2.3
10 N/A
N/A
3.8 7.3
100 N/A
N/A
12 23
For transmitters whose nominal output is not listed in the above table, the distance can be determined using the equation
in the relevant column, where P is the transmitter's maximum nominal output in Watt (W) as specified in the
information provided by the transmitter's manufacturer.
NOTE 1 The higher frequency range applies at 80 MHz and 800 MHz.
NOTE 2 The ISM frequency bands (for industrial, scientific and medical applications) between 150 kHz
and 80 MHz are 6.765 MHz to 6.795 MHz; 13.553 MHz to 13.567 MHz; 26.957 MHz to 27.283 MHz and 40.66 MHz to
40.70 MHz.
NOTE 3 The pass levels in the ISM frequency bands between 150 kHz and 80 MHz and in the frequency range
from 80 MHz and 2.5 GHz are intended to reduce the probability that mobile/portable communication devices might cause interference
if they are accidentally brought into the patient area. For this reason
the additional 10/3 factor is applied when calculating the recommended protection distances in these frequency ranges.
NOTE 4 These guidelines may not apply to all situations. The radiation of electromagnetic waves is influenced
by absorption and reflection from buildings, objects and people.
