RF Study (BLD-2021-1563)
YOUR RF SAFETY PARTNER
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RADIO FREQUENCY ELECTROMAGNETIC FIELDS EXPOSURE REPORT
Prepared for T-Mobile
c/o Smartlink, LLC
Site Name: PG&E Stelling Sub
Site ID: SF44041A
Site Type: Powerline Tower
Located at:
21090 Homestead Rd
Cupertino, CA 94087
Latitude: 37.3357 / Longitude: -122.0437
Report Date: 9/18/2020
Report By: Christopher Stollar, P.E.
Based on FCC Rules and Regulations, T-Mobile will be compliant provided
recommendation(s) are implemented.
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TABLE OF CONTENTS
1.0 EXECUTIVE SUMMARY ................................................................................................................................ 3
2.0 SITE DESCRIPTION ........................................................................................................................................ 4
2.1 Site Map ............................................................................................................................................................. 4
2.2 Antenna Inventory ........................................................................................................................................... 5
3.0 ANALYSIS ........................................................................................................................................................... 6
3.1 Emission Predictions ....................................................................................................................................... 6
4.0 CONCLUSION ................................................................................................................................................... 9
4.1 Results ................................................................................................................................................................ 9
4.2 Recommendation(s) ......................................................................................................................................... 9
4.3 Statement of Compliance ............................................................................................................................. 11
4.4 Engineer Certification ................................................................................................................................... 11
Appendix A: Background ........................................................................................................................................... 12
Appendix B: Measurement and/or Computer Simulation Methods ................................................................... 13
Appendix C: Limitations ............................................................................................................................................ 13
Appendix D: T-Mobile RF Advisory Signs ............................................................................................................. 14
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1.0 EXECUTIVE SUMMARY
Dtech Communications, LLC (“Dtech”) has been retained by Smartlink, LLC, contractors to T-Mobile, to
determine whether its wireless communications facility complies with the Federal Communications
Commission (“FCC”) Radio Frequency (“RF”) Safety Guidelines. This report contains a computer-
simulated analysis of the Electromagnetic Fields (“EMF”) exposure resulting from the facility. The analysis
also includes assessment of existing wireless carriers on site, where information is provided. The table
below summarizes the results at a glance:
Table 1: EMF Summary
T-Mobile Summary
Access Type Gates
Access to antennas locked Recommended
RF Sign(s) @ access point(s) NOC, Guidelines & Warning
(Recommended @ Tower Climbing Access)
RF Sign(s) @ antennas None
Barrier(s) @ sectors NA
Max EMF level for
T-Mobile on Ground 0.4% General Population
Max EMF level for
T-Mobile on Adjacent Roofs 0.9% General Population
Min Clearance Distance from Face of
T-Mobile’s Antennas 58 Feet
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2.0 SITE DESCRIPTION
The wireless telecommunication facility is located on the ground. The facility consists of 1 wireless
carrier(s) or operator(s): T-Mobile. The antennas are typically grouped into sectors pointing in different
directions to achieve the desired areas of coverage. T-Mobile’s antennas are mounted on a powerline tower
and connected to the equipment via coaxial cables.
2.1 Site Map
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2.2 Antenna Inventory
Technical specifications in the table below are provided by our clients and/or gathered from physical field
surveys where applicable and/or possible. Conservative estimates are used where information is not
provided or available.
Table 2: Site Technical Specifications
Note: Per T-Mobile direction, the AIR6449 ERP’s were calculated with an input power of 120W for the
NR and 40W for the LTE.
Antenna
ID Operator Antenna Mfg Antenna Model Type
Frequency
(MHz)Technology
Orientation
(°T)
Horizontal
BWdth (°)
Antenna
Aperture (ft)
Antenna
Gain (dBd)
Total ERP
(Watts)
Bottom Tip
Height Above
Ground (Z) (ft)
Bottom Tip
Height Above
Adj Roofs (Z) (ft)
Bottom Tip
Height Antenna
Level (Z) (ft)
A1 T-Mobile RFS APX16DWV-16DWV-S-E-A20 Panel 1900 GSM/UMTS/LTE 30 65 4.7 16.3 11945 89.7 59.7 0.0
A1 T-Mobile RFS APX16DWV-16DWV-S-E-A20 Panel 2100 LTE 30 65 4.7 16.3 5972 89.7 59.7 0.0
A2 T-Mobile Galtronics GP7204-06852 Panel 600 LTE 30 63 6.0 11.9 2168 89.0 59.0 0.0
A2 T-Mobile Galtronics GP7204-06852 Panel 700 LTE 30 67 6.0 12.1 2312 89.0 59.0 0.0
A3 T-Mobile Ericsson AIR6449 Panel 2500 NR 30 13 2.8 22.1 19244 90.6 60.6 0.0
A3 T-Mobile Ericsson AIR6449 Panel 2500 LTE 30 13 2.8 22.1 6415 90.6 60.6 0.0
B1 T-Mobile RFS APX16DWV-16DWV-S-E-A20 Panel 1900 GSM/UMTS/LTE 150 65 4.7 16.3 11945 89.7 59.7 0.0
B1 T-Mobile RFS APX16DWV-16DWV-S-E-A20 Panel 2100 LTE 150 65 4.7 16.3 5972 89.7 59.7 0.0
B2 T-Mobile Galtronics GP7204-06852 Panel 600 LTE 150 63 6.0 11.9 2168 89.0 59.0 0.0
B2 T-Mobile Galtronics GP7204-06852 Panel 700 LTE 150 67 6.0 12.1 2312 89.0 59.0 0.0
B3 T-Mobile Ericsson AIR6449 Panel 2500 NR 150 13 2.8 22.1 19244 90.6 60.6 0.0
B3 T-Mobile Ericsson AIR6449 Panel 2500 LTE 150 13 2.8 22.1 6415 90.6 60.6 0.0
C1 T-Mobile RFS APX16DWV-16DWV-S-E-A20 Panel 1900 GSM/UMTS/LTE 290 65 4.7 16.3 11945 89.7 59.7 0.0
C1 T-Mobile RFS APX16DWV-16DWV-S-E-A20 Panel 2100 LTE 290 65 4.7 16.3 5972 89.7 59.7 0.0
C2 T-Mobile Galtronics GP7204-06852 Panel 600 LTE 290 63 6.0 11.9 2168 89.0 59.0 0.0
C2 T-Mobile Galtronics GP7204-06852 Panel 700 LTE 290 67 6.0 12.1 2312 89.0 59.0 0.0
C3 T-Mobile Ericsson AIR6449 Panel 2500 NR 290 13 2.8 22.1 19244 90.6 60.6 0.0
C3 T-Mobile Ericsson AIR6449 Panel 2500 LTE 290 13 2.8 22.1 6415 90.6 60.6 0.0
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3.0 ANALYSIS
3.1 Emission Predictions
Figure 1: Plan (bird’s eye) view map of results compared to FCC’s General Population MPE (Maximum Permissible Exposure) Limits.
White represents areas where exposure levels are calculated to be at or below 5%; Green- between 5% & 100% (below MPE limits);
blue, yellow & red – greater than 100% (exceeds MPE limits). Individuals can safely occupy areas in white and green for indefinite
amount of time; whereas areas in blue, yellow & red must be restricted to RF trained personnel who has been made fully aware of potential
for exposure, has control and knows how to reduce their exposure with the use of personal protection equipment or has the ability to power
down the transmitters.
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Figure 2: Plan (bird’s eye) view map of results compared to FCC’s General Population MPE (Maximum Permissible Exposure) Limits.
White represents areas where exposure levels are calculated to be at or below 5%; Green- between 5% & 100% (below MPE limits);
blue, yellow & red – greater than 100% (exceeds MPE limits). Individuals can safely occupy areas in white and green for indefinite
amount of time; whereas areas in blue, yellow & red must be restricted to RF trained personnel who has been made fully aware of potential
for exposure, has control and knows how to reduce their exposure with the use of personal protection equipment or has the ability to power
down the transmitters.
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Figure 3: Plan (bird’s eye) view map of results compared to FCC’s General Population MPE (Maximum Permissible Exposure) Limits.
White represents areas where exposure levels are calculated to be at or below 5%; Green- between 5% & 100% (below MPE limits);
blue, yellow & red – greater than 100% (exceeds MPE limits). Individuals can safely occupy areas in white and green for indefinite
amount of time; whereas areas in blue, yellow & red must be restricted to RF trained personnel who has been made fully aware of potential
for exposure, has control and knows how to reduce their exposure with the use of personal protection equipment or has the ability to power
down the transmitters.
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4.0 CONCLUSION
4.1 Results
For a person standing in accessible areas on the ground and adjacent building roofs, calculations for
T-Mobile’s site resulted in exposure levels below the FCC’s most stringent General Population MPE Limits
(see figure 1 - 2).
At antenna elevation, the highest calculated exposure level is above the FCC’s General Population MPE
Limits near the T-Mobile antenna(s) (see figure 3). The overexposed (red, yellow and blue) areas extend
58-feet from the front face of the T-Mobile antenna(s). From the provided drawings, there are no other
buildings or surrounding structures at antenna elevation within 58-feet of the T-Mobile antenna(s). Beyond
58-feet, exposure levels are predicted to be below the FCC’s most stringent General Population MPE
Limits.
The antennas are mounted on a tall tower and therefore not accessible by the general public. It is presumed
that T-Mobile employees and contractors are aware of the transmitting antennas and will take appropriate
precautions when working near them. However, there may be situations where workers i.e. power-line
workers, etc. may find themselves directly in front of the antennas. Individuals working near/in front of
antennas must receive appropriate RF safety training and be made aware of the HotZones (areas where RF
exposure may potentially exceed FCC safety limits). In addition, contact information should be made
available in the event work is required within the HotZones.
4.2 Recommendation(s)
For the facility to be classified as an Occupational/Controlled environment, the following action(s) are
recommended in accordance with the FCC's RF Safety Guidelines (see figure 4):
1) Access to the facility should be kept locked to restrict routine access by the general public.
2) Install NOC Sign(s), GUIDELINES Sign(s) and WARNING Sign(s) at all tower climbing access
points, where they will be clearly visible to tower climbers.
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Figure 4: Recommendation(s)
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06/30/21
4.3 Statement of Compliance
Based on the above results, analysis and recommendation(s), it is the undersigned’s professional opinion
that T-Mobile’s site will be compliant with the FCC’s RF Safety Guidelines provided recommendation(s) are
implemented.
4.4 Engineer Certification
This report has been prepared by or under the direction of the following Registered Professional Engineer:
Darang Tech, holding California registration number 16000. I have reviewed this report and believe it to be
both true and accurate to the best of my knowledge.
________________________
Darang Tech, P.E.
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Appendix A: Background
Dtech uses the FCC’s guidelines described in detail in Office of Engineering & Technology, Bulletin No. 65
(“OET-65”) “Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency
Electromagnetic Fields”. The table below summarizes the current Maximum Permissible Exposure
(“MPE”) safety limits classified into two groups: General population and Occupational.
Table 3: FCC MPE Limits (from OET-65)
Frequency
(Mhz)
General Population/
Uncontrolled MPE
(mW/cm2)
Averaging
Time
(minutes)
Occupational/
Controlled MPE
(mW/cm2)
Averaging
Time
(minutes)
30 - 300 0.2 30 1.0 6
300 - 1500 Frequency (Mhz)/1500
(0.2 – 1.0) 30 Frequency (Mhz)/300
(1.0 – 5.0) 6
1500 -
100,000 1.0 30 5.0 6
General population/uncontrolled limits apply in situations in which the general public may be exposed or
in which persons who are exposed as a consequence of their employment, and may not be fully aware of the
potential for exposure or cannot exercise control over their exposure. Therefore, members of the general
public always fall under this category when exposure is not employment-related.
Occupational/controlled limits apply in situations in which persons are exposed as a consequence of their
employment, and those persons have been made fully aware of the potential for exposure and can exercise
control over their exposure. Occupational/controlled limits also apply where exposure is of a transient
nature as a result of incidental passage through a location where exposure levels may be above general
population/uncontrolled limits, as long as the exposed person has been made fully aware of the potential
for exposure and can exercise control over his or her exposure by leaving the area or by some other
appropriate means.
It is important to understand that the FCC guidelines specify exposure limits not emission limits. For a
transmitting facility to be out of compliance with the FCC's RF safety guidelines an area or areas where
levels exceed the MPE limits must, first of all, be in some way accessible to the public or to workers. When
accessibility to an area where excessive levels is appropriately restricted, the facility or operation can certify
that it complies with the FCC requirements.
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Appendix B: Measurement and/or Computer Simulation Methods
Spatial averaging measurement technique is used. An area between 2 and 6 feet, approximately the size of
an average human, is scanned in single passes from top to bottom in multiple planes. When possible,
measurements were made at very close proximity to the antennas and inside the main beam where most of
the energy is emitted. The spatial averaged values were recorded.
Dtech uses an industry standard power density prediction computer Model1 to assess the worse-case,
cumulative EMF impact of the surrounding areas of the subject site. The Model does not take into account
losses due to buildings. Its methodologies are conservative enough to account for typical down-tilts
deployed in wireless communications. In addition, the analysis is performed at 100% duty cycle-all
transmitters are active at all times and transmitting at maximum power. For purposes of a cumulative study,
nearby transmitters are included where possible. The result is a surrounding area map color-coded to
percentages of the applicable FCC’s MPE Limits. A result higher than 100% exceeds the Limits.
Appendix C: Limitations
The conclusions in this document rendered by Dtech are based solely upon the information collected during
the site survey and/or furnished by our Client which Dtech believes is accurate and correct. Dtech,
however, has no responsibility should such Client provided information prove to be inaccurate or
incorrect. Third party specification estimates used for cumulative computer simulation purposes, where
applicable, are based on common industry practices and our best interpretation of available information.
Data, results and conclusions in this document are valid as of its date. However, as mobile technologies
continuously change, these data, results and conclusions may also be at variance with such future changes.
Dtech has no responsibility to update its survey or report to account for such future technology changes.
This document was prepared for the use of our Client only and cannot be utilized by any third party for any
purpose without Dtech’s written consent. Dtech shall have no liability for any unauthorized use of this
document and any such unauthorized user shall defend, indemnify and hold Dtech and its owners, directors,
officers and employees harmless from and against any liability, claim, demand, loss or expense (including
reasonable attorney’s fees) arising from such unauthorized use.
1 Roofmaster(tm)
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Appendix D: T-Mobile RF Advisory Signs
GUIDELINES Sign
NOC Sign
NOTICE Sign
CAUTION Sign
WARNING Sign