TransCore 05716 Manuel D’Utilisation

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Multiprotocol Rail Reader System Guide
Health Limits for Multiprotocol Rail Reader Using Exter-
nal Antenna (902 to 928 MHz)
Within the United States, environmental guidelines regulating safe exposure levels are 
issued by the Occupational Safety and Health Administration (OSHA).
Section 1910.97 of OSHA Safety and Health Standards 2206 legislates a maximum 
safe exposure limit of 10 milliwatts per square centimeter (mW/cm
2
) averaged over 6 
minutes at 902 MHz.
Although not binding, other organizations such as the American National Standards 
Institute (ANSI) have issued similar guidelines that are more restrictive than the 
OSHA limits (ANSI C95.1). ANSI guidelines recommend a maximum safe power 
density in mW/cm
2
 
of:
Frequency (in MHz)
         1500
Thus, the maximum permissible exposure for general population/uncontrolled expo-
sure at 902 MHz is 0.60 mW/cm
2
. The power limit is a six-minute average.
The RF power density generated by the Multiprotocol Rail Reader (MPRR) was cal-
culated using a maximum antenna gain of 9.5 dBd, equivalent to the antenna gain of 
the external antenna.
Warning
At 2 W conducted into the antenna and a distance of 30 inches (77 cm) from the 
antenna, the maximum power density calculated was less than 0.60 mW/cm
2
. Install 
the antenna at least 30 inches (77 cm) from the general public. Maintenance per-
sonnel must remain at least 14 inches (35 cm) from antenna when system is operat-
ing.
The data confirms that the TransCore MPRR effectively meets OSHA requirements 
and thus does not represent an operating hazard to either the general public or mainte-
nance personnel.