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SIGMA Manual Number 41018
Revision AR
Note 1 At 80 M Hz a nd 800 MHz, the higher freque ncy range applies.
Note 2 These guid elines m ay n ot apply in all situations. Electromagne tic propagation is affected by
absorption and reflection from structures, objects and people.
a
The ISM (industrial, scientific, and m edical) band s between 150 kHz and 80 MH z are 6.756 M Hz to
6.795 M Hz; 13.553 MHz to 13.567 M Hz; 26.957 MHz to 27.283 M Hz; a nd 40.66 M Hz to 40.70 M Hz.
b
The ISM com pliance level in the ISM frequency band between 150 kHz and 80 MH z an d in the fre -
quency range 80 MH z to 2 .5 GH z are intended to de crease the likelihood that m obile/portable co mm uni-
cations equipment could cause interfe rence if it is inadvertently brought into patient areas. For this
reason an additional factor of 3K is used in calculating the re comm ended separation distance for trans-
m itters in these frequency ranges.
c
Field strength from fixed transm itters, such as base station s for radio (cellular/cordless) telephones
and land m obile radio, am ateur radio, AM and FM radio broadca st an d TV broadca st cannot b e predicted
theoretically with accuracy. To assess the electromagnetic e nvironme nt due to fixed RF transm itte rs, an
electrom agnetic site survey should be considered. If the mea sured field stren gth in the location in which
the Spe ctrum is used exceeds the applicable RF com pliance level above, the Spectrum shou ld be
observed to verify no rmal operation. If abnorm al perform ance is observed, additional m easures m ay be
necessary, such as reorienting or relocating the Spectrum.
d
Over the fre quency range 150 kHz to 80 M Hz, field strength should be less than 3 V/m.