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C Squared Systems 13 Forest Drive East Kingston, NH 03827 Phone 603-770-3143 Email [email protected]

Radio Frequency Exposure Compliance Report

Site: Woburn 5 555 Montvale Avenue Woburn, MA

XYZ Cellular 555 Hometown Road Anywhere, MA 055055

Woburn 5 - 555 Montvale Avenue

Table Of Contents 1. Introduction........................................................................................... 1 2. Site Description...................................................................................... 1 3. Detailed XYZ Cellular Antenna Information................................................

2

4. Antenna Pictures..................................................................................... 4 5. Roof Access and Site Signage.................................................................... 8 6. Adjacent Building or Obstructions............................................................... 13 7. Antenna Inventory................................................................................. 14 8. Site Map with Calculated and Measured % MPE Values.....................................16 9. 5% General Population MPE boundary for XYZ Cellular Antennas...................

17

10. Survey Procedure...................................................................................18 11. Site Survey Measurement Results...............................................................19 12. Modeling Procedures..............................................................................21 13. Results............................................................................................... 24 14. Conclusion.......................................................................................... 24

Attachment A - Engineering Certification.......................................................... 26

March 24, 2003

i

Woburn 5 - 555 Montvale Avenue 1. Introduction This report was prepared on behalf of XYZ Cellular to document an evaluation conducted on March 19, 2003, to determine compliance with the Federal Communications Commission's (FCC) radio frequency exposure rules, 47 CFR 1.1307(b)(1) ­ (b)(3), for the Woburn 5 transmission facility. Theoretical modeling calculations and survey measurements, expressed as a percentage of the Maximum Permissible Exposure (MPE) limits as listed in the FCC OET Bulletin 65, are presented herein. All modeling calculations and survey measurements were obtained using the methodology documented within this report. Robert McQue, who has completed RFE Safety training, conducted the field measurements and compiled the reported results. Then, Tony Wells reviewed in detail the results documented in this report. 2. Site Description The Woburn 5 site is located on the six-story Citizens Bank building located at 555 Montvale Avenue in Woburn, MA. XYZ Cellular antennas (See Map 1 of Section 8 for the antenna locations) are ballast mounted onto the rooftop of the building. Access to the rooftop is via a small access hatch, which is mounted into the rooftop directly above the sixth floor landing in the southern stairwell. XYZ Cellular equipment is installed within a dedicated room located on the sixth floor. In addition to XYZ Cellular, ABC Communications, Cingular, T-Mobile and Sprint PCS have equipment and antennas located at this site. All carriers are operating three sector systems. Sprint PCS has equipment enclosures mounted on the rooftop. Cingular, ABC Communications, and T-Mobile have dedicated equipment rooms located on the sixth floor of the building. General Information and Location:

Date Time Restricted Access Sign In Sheet Address Latitude (NAD83) Longitude (NAD83) Ground Elevation AMSL (feet) Structure Height (feet) Configuration Type of Service Access Contacts March 19, 2003 11:00 AM Yes (door locked) Yes ­ Log maintained in property management office 555 Montvale Avenue ­ Woburn, MA 42° 28' 45" N 71° 07' 5.8 " W 40 feet The main rooftop is 70 feet above ground level. 3 Sector System, Cellular AMPS, CDMA, TDMA, IDEN, PCS CDMA and GSM Contact Cell Tech ­ Joe Schmoe by phone at 617-555-1212 for access to building and equipment room or John at ACME Management Company at 781-555-1212

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Woburn 5 - 555 Montvale Avenue 3. Detailed XYZ Cellular Antenna Information Alpha Sector: The 4 antennas of Alpha sector are ballast mounted on the building's rooftop, near the northern facade. All antennas are evenly spaced approximately 4 feet apart. The centerline of each antenna is approximately 9 feet 3 inches above the rooftop level. See the site map for antenna locations. Alpha Sector

Antenna 1 2 3 4 Decibel Products Decibel Products Decibel Products Decibel Products Manufacturer DB844H90E-XY DB844H90E-XY DB844H90E-XY DB844H90E-XY Model 14.1 14.1 14.1 14.1 Gain (dBi) 90 90 90 90 Beamwidth ( Deg) 890 MHz 890 MHz 890 MHz 890 MHz Frequency XYZ Cellular XYZ Cellular XYZ Cellular XYZ Cellular Licensee 48" x 6.5" x 8" 48" x 6.5" x 8" 48" x 6.5" x 8" 48" x 6.5" x 8" Dimensions 9 feet 3 inches 9 feet 3 inches 9 feet 3 inches 9 feet 3 inches Above Roof Ht. 27° 27° 27° 27° Azimuth (ETN) 0° 0° 0° 0° Downtilt C D E F Grid Number

Beta Sector: Beta sector is comprised of 4 ballast-mounted antennas located on the building's rooftop, near the southeastern corner. All antennas are evenly spaced approximately 4 feet apart. The centerline of each antenna is approximately 9 feet 3 inches above the rooftop level. See the site map for antenna mount locations. Beta Sector

Antenna 1 2 3 4 Decibel Products Decibel Products Decibel Products Decibel Products Manufacturer DB844H90E-XY DB844H90E-XY DB844H90E-XY DB844H90E-XY Model 14.1 14.1 14.1 14.1 Gain (dBi) 90 90 90 90 Beamwidth ( Deg) 890 MHz 890 MHz 890 MHz 890 MHz Frequency XYZ Cellular XYZ Cellular XYZ Cellular XYZ Cellular Licensee 48" x 6.5" x 8" 48" x 6.5" x 8" 48" x 6.5" x 8" 48" x 6.5" x 8" Dimensions 9 feet 3 inches 9 feet 3 inches 9 feet 3 inches 9 feet 3 inches Above Roof Ht. 147° 147° 147° 147° Azimuth (ETN) 0° 0° 0° 0° Downtilt S T U V Grid Number

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Woburn 5 - 555 Montvale Avenue

Gamma Sector: Gamma sector is comprised of 4 ballast-mounted antennas located on the building's rooftop within 15 feet of the western façade. All antennas are evenly spaced approximately 4 feet apart. The centerlines of the Alpha Sector antennas are 14 feet 9 inches above the rooftop level. See the site map for antenna mount locations. Gamma Sector

Antenna 1 2 3 4 Decibel Products Decibel Products Decibel Products Decibel Products Manufacturer DB844H90E-XY DB844H90E-XY DB844H90E-XY DB844H90E-XY Model 14.1 14.1 14.1 14.1 Gain (dBi) 90 90 90 90 Beamwidth ( Deg) 890 MHz 890 MHz 890 MHz 890 MHz Frequency XYZ Cellular XYZ Cellular XYZ Cellular XYZ Cellular Licensee 48" x 6.5" x 8" 48" x 6.5" x 8" 48" x 6.5" x 8" 48" x 6.5" x 8" Dimensions 9 feet 3 inches 9 feet 3 inches 9 feet 3 inches 9 feet 3 inches Above Roof Ht. 267° 267° 267° 267° Azimuth (ETN) 0° 0° 0° 0° Downtilt MM NN OO PP Grid Number

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Woburn 5 - 555 Montvale Avenue 4. Antenna Pictures Picture 1 L M K N Q A F E D A C B PP A

I J H

G

Picture 2 C D E F

Rooftop Level

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Woburn 5 - 555 Montvale Avenue Picture 3

W L V

U

T S

R I

Q O N

P

M

Picture 4 Q F V U T R S

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Woburn 5 - 555 Montvale Avenue Picture 5 DD CC BB AA Z

Y

P

N

Picture 6

Rooftop Access Hatch

W X

V

Sprint Equipment Machinery Room Penthouse

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Woburn 5 - 555 Montvale Avenue Picture 7 HH MM PP LL KK W X EE

Sprint Equipment

SS RR RR QQ JJ II GG FF EE

Picture 8 KK LL NN OO PP

MM

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Woburn 5 - 555 Montvale Avenue 5. Roof Access and Site Signage Access to the roof is via a hatch mounted into the rooftop. The access hatch is located at the top of a metal ladder, which extends up from the sixth floor landing of the southern stairwell. This hatch was locked and a sign-in sheet was maintained within the sixth floor office of the Aberjona Company. Picture 9 shows the roof access hatch. Picture 10 shows the ladder that extends up from the sixth floor landing to the access hatch. Picture 9

Posted Safety Signage Rooftop Access Ladder

Picture 10

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Woburn 5 - 555 Montvale Avenue Picture 11 shows a detailed view of posted safety signage. Three carriers have signage posted at this site. XYZ Cellular signage consists of the yellow "Caution" and "Ten Point Guidelines" signs, which are portrayed as the two top signs. ABC Communications posted the yellow and white "Notice" sign. Sprint PCS installed the blue and white "Notice to Workers" sign. Picture 11

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Woburn 5 - 555 Montvale Avenue XYZ Cellular Equipment Room: XYZ Cellular equipment is installed in a dedicated room located on the sixth floor. Picture 12 shows the access door to the XYZ Cellular equipment room and Picture 13 shows details of posted signage. Picture 12

Picture 13

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Woburn 5 - 555 Montvale Avenue Other Carriers Equipment: Cingular, ABC Communications, and T-Mobile has equipment installed within a sixth floor rooms. Picture 14 shows the access door to the Cingular equipment room. Picture 15 shows the access door to area where the ABC Communications and T-Mobile (Omnipoint) equipment is located. Picture 14

Picture 15

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Woburn 5 - 555 Montvale Avenue Other Carriers Equipment: Sprint PCS has it equipment installed within outdoor equipment enclosures located on the buildings rooftop as portrayed in Pictures 6 and 7. Picture 16 shows a wide-angle view of the Sprint equipment and Picture 17 shows a close-up view of the main rack. Picture 16

Sprint Equipment Enclosures

Picture 17

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Woburn 5 - 555 Montvale Avenue 6. Adjacent Building or Obstructions The Citizen Bank building located at 555 Montvale Avenue, which houses the Woburn 5 site, is the tallest building in the immediate vicinity. There are no objects or structures that will cause reflections, which would contribute to the measured or calculated power density.

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Woburn 5 - 555 Montvale Avenue 7. Antenna Inventory The following information was utilized to perform theoretical calculations as described in the modeling procedures section of this report. The X, and Y coordinates for each antenna represent the 2 dimensional grid distances from an established reference point (X=0, and Y=0).

Ant # Operator TX Freq. (MHz) Power EIRP (Watts) Antenna Model Beam Width (Deg) X Y Az. Tilt Length Height Gain (Deg(feet) Above (dBi) ETN) Rooftop (feet) 0 0 27 27 27 27 20 20 20 20 25 25 25 145 145 145 30 30 147 147 147 147 150 150 140 140 140 0 0 0 0 0 0 5 5 5 5 3 3 3 2 2 2 7 7 0 0 0 0 0 0 3 3 3 4.25 4.25 4 4 4 4 4.25 4.25 4.25 4.25 4.33 4.33 4.33 4.33 4.33 4.33 6 6 4 4 4 4 6 6 4.25 4.25 4.25 -2.25 -2.25 9.25 9.25 9.25 9.25 -2.5 -2.5 -2.5 -2.5 -3 -3 -3 -3 -3 -3 11.5 11.5 9.25 9.25 9.25 9.25 11.5 11.5 -3 -3 -3 16 16 14.1 14.1 14.1 14.1 15.9 15.9 15.9 15.9 15 15 15 15 15 15 18.5 18.5 14.1 14.1 14.1 14.1 18.5 18.5 15.9 15.9 15.9

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z AA

Sprint Sprint XYZ Cellular XYZ Cellular XYZ Cellular XYZ Cellular Cingular Cingular Cingular Cingular ABC Coms ABC Coms ABC Coms ABC Coms ABC Coms ABC Coms T-Mobile T-Mobile XYZ Cellular XYZ Cellular XYZ Cellular XYZ Cellular T-Mobile T-Mobile Cingular Cingular Cingular

1950 1950 890 890 890 890 869.04 869.04 869.04 869.04 868 868 868 868 868 868 1945 1945 890 890 890 890 1945 1945 869.04 869.04 869.04

4803 4803 7050 7050 7050 7050 3527 3527 3527 3527 1927 1927 1927 1981 1983 1983 7591 7591 7050 7050 7050 7050 7281 7281 3432 3432 3432

CSA- PCSS090-13-2 CSA- PCSS090-13-2 DB844H90E-XY DB844H90E-XY DB844H90E-XY DB844H90E-XY DAPA- 3960-024* DAPA- 3960-024* DAPA- 3960-024* DAPA- 3960-024* Allgon- 7129.16.05.00 Allgon- 7129.16.05.00 Allgon- 7129.16.05.00 Allgon- 7129.16.05.00 Allgon- 7129.16.05.00 Allgon- 7129.16.05.00 EMS- RR651900DP EMS- RR651900DP DB844H90E-XY DB844H90E-XY DB844H90E-XY DB844H90E-XY EMS- RR651900DP EMS-RR651900DP DAPA- 3960-024* DAPA- 3960-024* DAPA- 3960-024*

90 90 90 90 90 90 60 60 60 60 85 85 85 85 85 85 65 65 90 90 90 90 65 65 60 60 60

86.42 97.42 82.98 80.96 78.92 76.92 97.73 97.73 97.73 97.73 86.75 86.75 86.75 83.00 79.98 76.79 69.71 63.26 50.11 47.21 44.36 41.50 33.32 25.67 55.67 51.58 47.54

76.08 59.00 47.73 44.23 40.73 37.25 47.75 43.67 39.63 35.58 13.46 10.38 7.21 3.25 3.25 3.25 22.54 14.88 19.04 21.93 24.79 27.61 37.93 44.35 3.22 3.22 3.22

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Woburn 5 - 555 Montvale Avenue

BB CC DD EE FF GG HH II JJ KK LL Cingular Sprint Sprint Sprint Sprint Cingular Cingular Cingular Cingular T-Mobile T-Mobile 869.04 1950 1950 1950 1950 869.04 869.04 869.04 869.04 1945 1945 890 890 890 890 868 868 868 3432 5916 5916 6168 6168 3527 3527 3527 3527 6984 6984 7050 7050 7050 7050 1927 1927 1927 DAPA- 3960-024* CSA- PCSS090-13-2 CSA- PCSS090-13-2 CSA- PCSS090-13-2 CSA- PCSS090-13-2 DAPA- 3960-024* DAPA- 3960-024* DAPA- 3960-024* DAPA- 3960-024* EMS- RR651900DP EMS- RR651900DP DB844H90E-XY DB844H90E-XY DB844H90E-XY DB844H90E-XY Allgon- 7129.16.05.00 Allgon- 7129.16.05.00 Allgon- 7129.16.05.00 60 90 90 90 90 60 60 60 60 65 65 90 90 90 90 85 85 85 43.53 20.38 8.44 8.55 20.50 29.02 33.08 37.13 41.15 42.46 52.47 58.90 62.96 67.00 71.03 62.11 65.18 68.38 3.22 22.54 22.54 58.42 58.42 78.79 78.79 78.79 78.79 62.29 62.29 63.50 63.50 63.50 63.50 77.75 77.75 77.75 140 120 120 240 240 260 260 260 260 270 270 267 267 267 267 265 265 265 3 0 0 0 0 3 3 3 3 0 0 0 0 0 0 0 0 0 4.25 4.25 4.25 4.25 4.25 4.25 4.25 4.25 4.25 6 6 4 4 4 4 4.33 4.33 4.33 -3 -2.25 -2.25 -2.25 -2.25 -2.5 -2.5 -2.5 -2.5 11.5 11.5 9.25 9.25 9.25 9.25 -3 -3 -3 15.9 16 16 16 16 15.9 15.9 15.9 15.9 18.5 18.5 14.1 14.1 14.1 14.1 15 15 15

MM XYZ Cellular NN XYZ Cellular OO XYZ Cellular PP XYZ Cellular QQ RR SS ABC Coms ABC Coms ABC Coms

*The model number and manufacturer of each antenna were recorded by visual inspection at the site. In this case, only the manufacturer name was visible on the antenna. For these antennas, the pattern from suitable antennas was selected after consideration of the antenna size and operating frequency of the carrier.

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Woburn 5 - 555 Montvale Avenue 8. Site Map with Calculated and Measured % MPE Values Site Map 1 provides a visual representation of the RF environment at the Woburn 5 site and depicts antenna locations and rooftop structures. Additionally, this map shows calculated "worst case" results, based on software modeling, along with actual field measurement points. The site map below depicts the cumulative power density levels, for various heights (main rooftop, machinery room penthouse rooftop, and Sprint equipment platform, which are overlaid onto one map. Site Map 1: Percent of FCC General Public Exposure Limit, All Carriers

GG

QQ JJ SS HH II 16 RR 29 17 8 28 15 KK 18 PP LL MM NN OO 30 27 19 26 31

40

A

EE 3 10 9 2

FF 7

39

B 41 42 H I G

Sprint Equipment

X 6

14 W 13 V 12

38C D E 44

Penthouse

20 U T S 21

25 32

F 37 36 K

43 J

1 DD

Access Hatch

CC

5

Q 33 R 24

4

11 BB

22 AA Z

23 Y

L 34 O 35 M N P

* The calculated %MPE values for the above grid reflect multi-level analysis to represent the exposure level at various heights (Main rooftop versus penthouse rooftop and Sprint equipment platform).

Site Map Legend

< General Population MPE > General Population MPE < Occupational/ Controlled MPE > Occupational/Controlled MPE

A Antenna ID ## Field measurement point (See Section 11 for values)

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Woburn 5 - 555 Montvale Avenue 9. Site map for XYZ Cellular Antennas Site Map 2 provides a visual representation of the RF environment from XYZ Cellular antennas only. The data is presented as a percentage of the General Population MPE limit and is presented in two colors. The transition from blue to green is the 5% boundary of the General Population limit. Site Map 2: 5 % General Population MPE Boundary, XYZ Cellular Antennas Only

GG

QQ JJ SS HH II 16 RR 29 17 8 28 15 KK

40

A

EE 3 10 9 2

FF 7

18 PP LL MM NN OO 30 39 27 19 26 31 38C D E 44

B 41 42 H I 43 G

Sprint Equipment

X 6

14 W 13 V 12

Penthouse

20 U T S 21

25 32

F 37 36 K

J

1 DD

Access Hatch

CC

5

Q 33 R 24

4

11 BB

22 AA Z

23 Y

L 34 O 35 M P N

*The calculated %MPE values for the above grid reflect multi-level analysis to represent the exposure level at various heights (Main rooftop versus penthouse rooftop and Sprint equipment platform).

Site Map Legend

< 5% General Population MPE > 5% General Population MPE

A Antenna ID ## Field measurement point (See Section 11 for values)

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Woburn 5 - 555 Montvale Avenue 10. Survey Procedure Sampling Description: The rooftop area of the site under evaluation is laid out in a grid of measurement points along with particular points of interest. At each measurement point, a spatially averaged measurement is collected over the height of an average human body. The 8718B survey meter performs a time average measurement while the user slowly moves the probe over a distance range of 0 cm to 200 cm (about 6 feet) above the rooftop level. The results recorded at each measurement location include both average and peak values over the spatial distance. The results of the site survey measurement are presented in section 11. Each measurement point includes its spatial average and peak value corresponding to the sampled locations identified numerically on the site map of Section 8. It should be noted that the accuracy of these measurements are dependent on a number of variables including: the active transmitters and channels at the given time of day; measurement uncertainty of the E-field probe; and one's ability to accurately position themselves over the same measurement point location. In addition, the sampling results do not take in to account possible future channel expansion. For these reasons, compliance with the FCC MPE limits is determined by the worse case results of the survey measurements and the modeling calculations described in section 12. Both are presented on the site map of section 8. Instrumentation:

Manufacturer Probe Calibration Date Calibration Interval Meter Calibration Date Calibration Interval Probe Specifications

NARDA Microwave A8722D, Serial Number 07030 06/19/02 12 Months 8718B, Serial Number 06028 06/14/02 12 Months Freq Range Field Measured 300 KHz-50 GHz E

Standard FCC 1997

Measurement Range .3-300% of Controlled

Instrument Measurement Uncertainty: The total measurement uncertainty of the NARDA measurement probe and meter is no greater than ±3 dB. The factors which contribute to this include the probe's frequency response deviation, calibration uncertainty, ellipse ratio, and isotropic response. Every effort is taken to reduce the overall uncertainty during measurement collection including rotating the probe about the axis of the handle and pointing the probe directly at the likely highest source of emissions.

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Woburn 5 - 555 Montvale Avenue 11. Site Survey Measurement Results Site survey measurements were recorded in accordance with the procedure of section 10. The measurements were recorded between the hours of 11:30 AM to 12:30 PM on Wednesday, March 19, 2003.

Measurement Point 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 Date 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 Average % General Population MPE 2.25 1.5 0.4 3.45 3.6 2.45 2 2.45 11.95 1.45 4.05 9.4 2.55 3 3.1 2 3.95 3.9 4.45 4.05 3.95 4.15 4.45 3.3 4.7 5.75 3.15 5.8 5.35 2.65 2.05 1.8 2.45 1.8 6 5.15 8.3 3.95 Max Peak % General Population MPE 4.15 4.9 1.6 12.75 9.4 3.2 3.65 3.45 29.25 2.25 8.35 82.65 6.65 20.7 21.2 4.4 12.55 12.4 10.8 12 15 22.2 10.7 7.5 21.55 37.95 19.6 14.55 34.3 31.8 26.7 15.4 12.85 5.05 19.8 15.65 15.95 15

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Woburn 5 - 555 Montvale Avenue

Measurement Point 39 40 41 42 43 44

Date 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003 3/19/2003

Average % General Population MPE 5.1 4.65 2.1 4.6 3.2 14.8

Max Peak % General Population MPE 31.6 28.8 15.75 21.95 13.7 40.15

NOTE: Measurement points 9 & 10 recorded on Sprint equipment platform, which is elevated 40 inches above the rooftop.

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Woburn 5 - 555 Montvale Avenue 12. Modeling Procedures The modeling calculations assume that the antennas are operating at 100 percent capacity; that all antenna channels are transmitting simultaneously and that the radio transmitters are operating at full power. Obstructions (trees, buildings etc.) that would normally attenuate the signal are not taken into account. As a result, the predicted signal levels are more conservative (higher) than the actual signal levels will be from the measurement conclusions. The emission field calculation results displayed on the site map were generated using a proprietary computer software modeling prediction tool, PDcalc, as developed and provided by C Squared Systems. PDcalc, uses the following power density calculation formulas: Dish Antennas: Near Field:

D2 End of Near Field = (4 × )

Power Density Near = PDN =

16 × A × P × D2

Where: D = Antenna Diameter = Wavelength A = Aperture Efficiency P = Power Input to the Antenna 20 dB of attenuation is added for any points greater than one antenna diameter from the main beam.

Transition Region:

End of Transition Region = (2× D 2 )

Power Density Transition =

PDN × Near Region R

Where: D = Antenna Diameter = Wavelength PDN = Power Density Near

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Woburn 5 - 555 Montvale Avenue R = Radial Distance D2 Near Region = (4 × ) 20 dB of attenuation is added for any points greater than one antenna diameter from the main beam. Far Field:

2.56 × EIRP Power Density = × Off Beam Loss 2 4 × × R Where: Off Beam Loss is determined by the selected antenna patterns R = Radial Distance

Directional and Omni Antennas:

Near Field: S= Pt × K (H a , La ) BW 20 × × La × Rh × 360 Where: S = Power Density in mw/cm2 Pt = Actual (or worst case assumed) power delivered to the antenna (watts) K(Ha , La) = Correction factor for antenna mounting height Ha = Antenna mounting height in feet La = Antenna length in meters Rh = the horizontal distance along roof from antenna to point of interest BW = Antenna beamwidth K(Ha , La) = 0.99013 - 0.14656 × H a for 0 Ha 6 for Ha > 6 = 1/ Ha If the horizontal distance from the bottom of the antenna is < 1 foot, then 1 foot is used for the distance. In order to deal with directional antennas, a modified cylindrical model is used. This is done by approximating the horizontal pattern with a model that is conservative, and applying the results to the cylindrical model above. The equation to be used is: A = cos n 2

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Woburn 5 - 555 Montvale Avenue Where: A = Attenuation = Angle between antenna azimuth and point in question n = Factor to shape the function for a particular beamwidth BW = Antenna beamwidth By setting the attenuation equal to 0.5 at the half power point ( = BW 2 ) , n can be solved. However, in order to ensure that the attenuation model is conservative, n is solved when = (BW 2 ) × (4 3) . This essentially assumes a larger beamwidth for margin. Therefore, solving for n, we have n= ln(0.5) ln(cos( BW / 3))

As a result, antennas with a beamwidth wider than 270° will be treated as an omnidirectional antenna. Finally, the maximum attenuation is capped at 15 dB to assure a conservative result in the rear of the antenna.

Far Field:

2.56 × EIRP Power Density = × Off Beam Loss 2 4 × × R

Where: EIRP = Effective Isotropic Radiated Power R = Radial Distance = H 2 + V 2 H = Horizontal Distance from antenna V = Vertical Distance from bottom of antenna Off Beam Loss is determined by the selected antenna patterns

(

)

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Woburn 5 - 555 Montvale Avenue

13. Results

The calculated modeling results, displayed on Site Map 1 in Section 8, reveal cumulative power density levels that exceed both the General Population/Uncontrolled and Occupational/Controlled MPE limits, as indicated by the yellow and red colors respectively. Worse case "Hot Spots" are indicated, directly in front of XYZ Cellular antennas, and are calculated to be 1278 % above the General Population limits. Power density levels must remain below 100% in order to comply with the General Population/Uncontrolled limits and less than 500% to comply with the Occupational/Controlled MPE limits. The site survey measurement results, as referenced on the site map and listed in section 11, indicate cumulative power density levels below the General Population/Uncontrolled MPE limits. The "worst case" measured power density of 14.8 % was detected 4 feet directly in front of XYZ Cellular's Alpha sector antennas. The analysis of XYZ Cellular antennas using modeling calculations, as presented in Site Map 2 within Section 9, reveal power density levels above the 5% General Population limit over a majority of the rooftop.

14. Conclusion

XYZ Cellular is one of five carriers with equipment and antennas installed at this location. Calculated power density levels from XYZ Cellular antennas exceed the 5% General Population MPE limit over a majority of therooftop. Upon implementation of the following recommendations, the Woburn 5 site at 555 Montvale Avenue in Woburn 5, MA will be in compliance with the FCC's Maximum Permissible Exposure Limits.

Recommendation:

Control RF exposure by restricting access to the rooftop and implement a RF Health and Safety Protection Program for this location in order to comply with FCC and OSHA requirements. The program must include the following: 14.1.1 - Control Access to the Roof The roof top access hatch is currently kept locked. The RF Safety program requires that the rooftop access door remain locked at all times. Access to the rooftop must be controlled and permitted to only personnel trained in RF safety awareness. A log should be maintained to keep a record of those granted access and their most recent RF safety training.

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Woburn 5 - 555 Montvale Avenue 14.1.2 ­ RF Awareness All personnel working on the rooftop site must understand and work within the bounds of an RF Safety Program such as XYZ Cellular's RFE Compliance Program. 14.1.3 - Site Specific Clearance Requirements All authorized personnel working on the rooftop, in the vicinity of XYZ Cellular antennas, shall maintain the following clearances to avoid RF exposure in excess of the FCC guidelines for Occupational/Controlled MPE.

Alpha Sector, cluster of 4 antennas mounted onto a metal frame assembly near the northern facade (parallel to Montvale Avenue) of the building: Avoid the area directly below and in front of the antennas extending outwards at least 6 feet. Beta Sector, cluster of 4 antennas mounted onto a metal frame assembly near the southeastern corner (perpendicular to I 93) of the building: Avoid the area directly below and in front of the antennas extending outwards at least 6 feet. Gamma Sector, cluster of 4 antennas mounted onto a metal frame assembly parallel with the western facade (parallel to adjacent restaurants and facing away from I 93) of the building: Avoid the area directly below and in front of the antennas extending outwards at least 6 feet.

Contact XYZ Cellular if access is required to the areas described above. Currently no HVAC equipment, vents, or other machinery is located within the clearance areas described above.

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Woburn 5 - 555 Montvale Avenue

Attachment A - Engineering Certification

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