Engineering StatementPage 1 of 1
Machelle Hill
From: Sonya Watters
Sent: Thursday, July 15, 2010 6:02 PM
To: Barbara Shiffer; Jacy Jones; Jaycee Holman; Machelle Hill
Subject: FW: Clearwire CUP
Attachments: 2684_001. pdf
Additional info for application
From: Jason Evans [mailto:jasonevans@cableone.net]
Sent: Thursday, July 15, 2010 3:53 PM
To: Sonya Watters
Subject: RE: Clearwire CUP
Engineer letter is attached.
Everything else looks good. I'll work on the landscape issue with the CZC.
Thanks,
Jason Evans
(208) 344-3594 -Desk
(208) 866-7725 - PCS
JasonEvans@cableone.net
From: Sonya Watters [mailto:swatters@meridiancity.org]
Sent: Thursday, July 15, 2010 1:53 PM
To: Jason Evans
Subject: Clearwire CUP
Hi Jason,
Just checking in before the hearing tonight to see if you had any issues with the staff report or if you were in
agreement with the conditions of approval. If you can submit a written response to the staff report, that would be
great.
Thanks,
sow~a Watters
Associate City Planner
City of Meridian -Planning Department
33 E. Broadway Avenue, Suite 210
Meridian, Idaho 83642
208.884.5533 ph. / 208.888.6854 fax
7/15/2010
clear
EVALUATION OF COMPLIANCE WITH GUIDELINES FOR HUMAN
EXPOSURE TO RADIO FREQUENCY RADIATION
for
Clearwire LLC
INTRODUCTION
This engineering statement was prepared to analyze the expected level of Non-Ionizing Electromagnetic Radiation
("NIER") caused by the addition of radio transmission equipment belonging to Clearwire at the following proposed radio
frequency transmitter site:
Site Name: ID-601104
Site Address: 3800 North Locust Grove road
City, State: Meridian, ID
Coordinates (NAD83): 43-38-30.97 N / 116-22-15.78 W
ANALYSIS
In 1985, the FCC adopted the 1982 ANSI guidelines for purposes of evaluating exposure due to RF transmitters licensed
and authorized by the FCC. In 1992, ANSI adopted the 1991 IEEE standard as an American National Standard (a revision
of its 1982 standard) and designated it ANSI/IEEE C95.1-1992. In 1996, the FCC adopted a modified version of its
original proposal. The FCC's action also fulfilled requirements of the Telecommunications Act of 1996 for adopting new
RF exposure guidelines. The FCC considered comments submitted by the EPA, FDA, NIOSH and OSHA, which have
primary responsibility for health and safety in the Federal Government.
The FCC's guidelines are based on recommended exposure criteria issued by the NCRP and ANSI/IEEE and are similar
to the ANSI/IEEE 1992 guidelines except for differences in recommended exposure levels at lower frequencies and higher
frequencies, and for controlled and uncontrolled access areas. Over a broad range of frequencies, NCRP exposure limits
for the public are generally one-fifth those for workers in terms of power density.
The NCRP and ANSI/IEEE exposure criteria are frequency dependent since the whole-body human absorption of RF
energy varies with the frequency of the RF signal. The most restrictive limits on exposure are in the frequency range of
30-300 MHz where the ,human body absorbs RF energy most efficiently .when exposed _ in the far field of an RF
transmitting source. The exposure limits adopted by the FCC in 1996 are shown in Appendix 1. The NCRP and
ANSI/IEEE exposure criteria and most other standards also specify "time-averaged" MPE limits. This means that it is
permissible to exceed the recommended limits for short periods of time as long as the average exposure (over the
appropriate period specified) does not exceed the limit. For example, Appendix 1 shows that for a frequency of 100 MHz
the recommended power density limit is 1 mW/cm with an averaging time of six minutes (any six-minute period) for
occupational/controlled exposure.
The Clearwire proposed transmitters operate in the FCC EBS/BRS services and broadcast in the 2500 - 2690 MHz
frequency range. In addition, there may be additional point-to-point microwave transmitters operating between 5 and 23
GHz (see Table 1). Therefore, the proposed new transmitters will fall into the 1500-100,000 MHZ frequency band for
NIER evaluation. The mandated maximum NIER limit for the 1500-100,000 MHz band for a "General
z
Population/Uncontrolled Exposure" area is 1 mW/cm
Site Address: 3800 N Locust Grove Road, Meridian, ID, 83646
Latitude: 43-38-30.97 N Longitude 116-22-15.78 W
Site is ror~~pl't~tr~f
._ _ _ __ _ ___._ _i
echnolo WiMax GSM CDMA Backhaul Unit
ite Name: Clearwire N/A N/A Clearwire
ite Number: ID-6010104 Backhaul
Fre uenc of Carrier: 2600 5800 MHz
otal # of Carriers: 6.0 1.0 Numeric
EIRP er Carrier in dbm from Link Bud et: 56.0 55.6 dBm
ERP er Carrier from Link Bud et: 243.22 221.82 Watts
otal ERP 1459.32 221.82 Watts
otal ERP 31.6 23.5 dBW
RC Hei ht Above Ground Y : 75 75 Feet
Distance Between Tower and Closest Point Worker
ould Be'` X1 12 12 Feet
Distance Between Tower and Closest Point on Fence
Line* X2 20 20 Feet
Radial Distance to Worker Point of Interest R1 : 2315.1 2315.1 centimeters
Radial Distance to Public Point of Interest R2 : 2365.9 2365.9 centimeters
n le from horizon to Worker Point of Interest 80.9 80.9 Degrees
n le from horizon to Closest oint on Fence Line 75.1 75.1 Degrees
ntenna centerline mechanicallelectricat down tilt, if
an 2 0 Degrees
ngle between antenna centerline and radial to
Worker Point of Interest 78 9 80.9 Degrees
ngle between antenna centerline and radial to
Closest Point on Fence Line 73.1 75.1 Degrees
Difference between maximum antenna gain and and
antenna ain alon radial to Worker oint of interest 43 43 d6
Difference between maximum antenna gain and and
ntenna gain along radial to Closest Point on Fence
Line
36
36
dB
ERP at antenna toward Worker Point of Interest -11.4 -19.5 dBW
ERP at antenna toward Closest Point on Fence Line -4.4 -12.5 dBW
ERP at antenna toward Worker Point of Interest 73.139 11.117 milliwatts
ERP at antenna toward Closest Point on Fence Line 366.565 55.719 milliwatts
Power Densi Worker Point of Interest: 0.0000071 0.0000011 mW/cm2
Power Densit Public Point of Interest: 0.0000068 0.0000010 mW/cm2
NSI 1992 Standard MPE:
Controlled Environment Worker : 5.000 5.000 mW/cm2
Uncontrolled Environment Public : 1.000 1.000 mW/cm2
Percenta a of Total MPE er Technolo Wimax-
Clearwire CDMA-Clearwire-
Backhaul
Controlled Environment Worker : 0.000142 0.000022
Uncontrolled Environment Public : 0.000682 0.000104
Percenta a of Total MPE for Cell Site:
Controlled Environment Worker : 0.000582
Uncontroiled Environment Public : 0.002680
Clearwire Contribution Worker 0.000560
Clearwire Contribution Public 0.002576
* X1 refers to the horizontal distance between the base of the
tower and the nearest point on the property that a worker would
work for any length of time e.g. a transmitter shed.
X2 refers to the horizontal distance between the base of the tower
and the nearest point on the property fine that the public could
walk up to or have access e.g. closest point on fence line.
As shown in Table 1, the cumulative transmissions at this site with the addition of the proposed Clea_rwire transmissions is
well below the 100% limit and no exposure risk should exist
.~'"
Thomas Tran
Manager - RF Engineering
clear,;`;, i M: (2A6) 321-2£377
1475 12UtP~ 5t NG ~ 33ellevue, WA 9F3C)05