RF Safety Evaluation for W3ZR's
Station
This is a main beam power density estimation intended for use as
part of a routine evaluation of RF safety compliance with FCC regulations.
Beginning January 1, 1998, Amateur Radio operators licensed by the Federal
Communications Commission of the United States of America will be required to
do a "routine evaluation" of the strength of the RF fields around
their stations. Operators who use transmitter power of 50 watts or less peak
envelope power, and mobile stations using push-to-talk microphones (regardless
of power) are exempt from the routine evaluations (but not exempt from
compliance with the exposure limits.) These new rules can be found in the FCC's
ET Docket No. 93-62. More information can be found at the ARRLWeb's RF Safety
page.
This estimation used the formulas given in FCC OET Bulletin No. 65 to
estimate power density in the main lobe of an antenna, with use of the
EPA-recommended ground reflection factor as an option. This estimation is
intended for approximate far-field calculations. It may overestimate the actual
field strength of high-gain antennas in the near field (within several
wavelengths of the antenna.) However, it may also underestimate the strength of
fields that may be encountered in hot spots in the near field.
|
Calculation Results - 80/75 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
3.750 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
64.00 mw/cm2
|
12.81 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
2.97 feet
|
6.58 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 40 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
7.150 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
17.61 mw/cm2
|
3.53 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
5.62 feet
|
12.50 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 30 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
10.125 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
8.78 mw/cm2
|
1.76 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
7.94 feet
|
17.68 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 20 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
14.175 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
4.48 mw/cm2
|
0.90 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
11.09 feet
|
24.73 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 17 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
18.125 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
2.74 mw/cm2
|
0.55 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
14.17 feet
|
31.61 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 15 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
21.175 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
2.01 mw/cm2
|
0.41 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
16.54 feet
|
36.93 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 12 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
24.950 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
1.45 mw/cm2
|
0.29 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
19.48 feet
|
43.50 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 10 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
28.800 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
1.09 mw/cm2
|
0.22 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
22.48 feet
|
50.20 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 6 Meters
|
Average
Power at the Antenna
|
1500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
100.00 feet
|
|
Frequency
of Operation
|
52.000 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0546 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
1.00 mw/cm2
|
0.21 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
23.41 feet
|
52.29 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 2 Meters
|
Average
Power at the Antenna
|
500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
50.00 feet
|
|
Frequency
of Operation
|
146.000 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0728 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
1.00 mw/cm2
|
0.21 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
13.54 feet
|
30.21 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 1.25 Meters
|
Average
Power at the Antenna
|
500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
50.00 feet
|
|
Frequency
of Operation
|
222.000 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0728 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
1.00 mw/cm2
|
0.21 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
13.54 feet
|
30.21 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 70 cm
|
Average
Power at the Antenna
|
500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
50.00 feet
|
|
Frequency
of Operation
|
440.000 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0728 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
1.47 mw/cm2
|
0.30 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
11.19 feet
|
24.96 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 33 cm
|
Average
Power at the Antenna
|
500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
50.00 feet
|
|
Frequency
of Operation
|
915.000 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0728 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
3.05 mw/cm2
|
0.61 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
7.77 feet
|
17.32 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
|
Calculation Results - 23 cm
|
Average
Power at the Antenna
|
500.000 watts
|
|
Antenna
Gain in dBi
|
2.20 dBi
|
|
Distance
to the Area of Interest
|
50.00 feet
|
|
Frequency
of Operation
|
1270.000 MHz
|
|
Are
Ground Reflections Calculated?
|
Yes
|
|
Estimated
RF Power Density
|
0.0728 mw/cm2
|
|
|
|
Controlled
Environment
|
Uncontrolled
Environment
|
|
Maximum
Permissible Exposure (MPE)
|
4.24 mw/cm2
|
0.85 mw/cm2
|
|
Distance
to Compliance From Center of Antenna
|
6.61 feet
|
14.71 feet
|
|
Does
the Area of Interest Appear to be in Compliance?
|
yes
|
yes
|
|
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