Citizen CH-617 Mode D'emploi page 28

For transmitters rated at a maximum output power not listed above, the
recommended separation distance d in metres (m) can be estimated using
the equation applicable to the frequency of the transmitter, where P is the
maximum output power rating of the transmitter in watts (W) according to
the transmitter manufacturer.
NOTE 1 At 80 MHz and 800 MHz, the separation distance for the higher
frequency range applies.
NOTE 2 These guidelines may not apply in all situations. Electromagnetic
propagation is affected by absorption and reflection from structures, objects
and people.
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