RADIO FREQUENCY NIER REPORT

Transcription

1 RADIO FREQUENCY NIER REPORT City of Albany Cellular Sites Prepared for: City of Albany Prepared August 26, 2013 by: Peter Gruchawka, President Accord Communications (707) Accord Communications 2013 This report may be reproduced for the City of Albany (in COLOR only, as important information may be lost in a black and white copy) and distributed to its staff, contractors, site operators and the general public. Such copies may be used as part of the supporting information that demonstrates compliance with FCC ET Docket The report form and content may not be used for any other purpose without the express written permission of Accord Communications. D P /M T

2 CONTENTS PROJECT Page 3 SCOPE AND PURPOSE Page 3 ASSESSMENT CRITERIA Page 4 METHOD OF ANALYSIS Page 4 REPORT CONCLUSIONS Page 5 TABLES, PHOTOGRAPHS AND FIGURES Page 7 TABLE ONE and FIGURE 1 FCC Limits for Maximum Permissible Exposure (MPE) Page 8 TABLE TWO Test Equipment Used During the Project Page 11 TABLE THREE Data Points vs. Percent of Standard Page 14 PHOTOGRAPHS Page 16 ATTACHMENTS Page 19 ATTACHMENT A Definitions Page 20 ATTACHMENT B Credentials of Accord Communications Page 23

3 RADIO FREQUENCY NIER REPORT City of Albany Cellular Sites PROJECT The project is described as: Determining if the cellular provider sites within the city limits meet the Federal Communications Commission (FCC) standards for radio frequency (RF) exposure for Occupational/Controlled and General Population/Uncontrolled exposures. Specifically the facilities located at: 1600 Posen (SMCHS) - (roof mount) 929 San Pablo - (sign) 423 San Pablo Ave - (pole) 650 Cleveland - (pole) 520 Cleveland - (pole) 1035 San Pablo Ave - (roof mount) Golden Gate Fields (view tower) Including all the existing transmitter facilities in operation as of the date of the field survey. If the peak field strength found is less than 10% of Occupational/Controlled no data points will be noted. Conducting the Project using FCC guidelines in FCC ET Docket and OET Bulletin 65. Recommending mitigation measures, if necessary, to achieve compliance with FCC ET Docket SCOPE AND PURPOSE This report summarizes the field study conducted to identify if the existing telecommunication facilities will expose the public or employees in the equipment room and the accessible area surrounding the antennas, to ambient Nonionizing Electromagnetic Radiation (NIER) exceeding Page 3

4 the FCC ET Docket standards. The FCC ET Docket standards and associated Office of Engineering and Technology OET Bulletin 65 (August 1997) outline recommended techniques for quantifying electromagnetic fields and provides data on safe levels of NIER. This study will analyze compliance issues in relation to FCC ET Docket Mitigation measures, if necessary, will be recommended to assist in achieving compliance with FCC ET Docket ASSESSMENT CRITERIA FCC safety levels with respect to human exposure are used in this study. The data in FCC ET Docket Table 1 and Figure 1, Limits for Maximum Permissible Exposure (MPE) will be applied in the analysis of the facility. Since numerous antennas operating at various frequencies are in place, the only practical approach is to determine NIER exposure in the equipment room, on buildings and in the accessible surrounding area is by field measurement. Paragraph 6.4 of American National Standards Institute ANSI C states the absorption and distribution of electromagnetic energy in the body are very complex phenomena that depend on the mass, shape and size of the body, the orientation of the body with respect to the field vectors, and the electrical properties of both the body and the environment. Other variables that may play a substantial role in possible biological effects are those that characterize the environment (e.g., ambient temperature, air velocity, relative humidity, and body insulation) and those that characterize the individual (e.g., age, gender, activity level, debilitation or disease). Because innumerable factors may interact to determine the specific biological outcome of an exposure to electromagnetic fields, the ANSI Standards consider maximal amplification of biological effects as a result of field-body interactions, environmental conditions and physiological variables. The Limits for Maximum Permissible Exposure (MPE) in FCC ET Docket Table One are based on an ANSI standard and methodology. METHOD OF ANALYSIS Table Two provides the specifications of the survey equipment used in the study. The sites were scanned for peak fields, during normal equipment operation, in the area surrounding the operating antennas. The perimeter and central area of the site was scanned and the points of maximum field strength were found. When the peak power density exceeds 10% of Occupational/Controlled levels, but is less than 300%, the field will be spatially averaged and logged. The FCC standard states that the points of potential human exposure are to be spatially averaged over the length of a human (2 meters in height for this standard). This value must not exceed the Maximum Permissible Exposure Page 4

5 (MPE). Table Three provides the peak and spatial averaged power density in percent of standard. The data points are the highest measured field strengths as found on July 31, Each data point was spatially averaged using a minimum of two hundred data points to assure the accuracy of the results. REPORT CONCLUSIONS Review of the data supports the following conclusions and recommended mitigation: 1. The spatially averaged NIER on the grounds, building roofs, within the fenced compounds and the surrounding area outside the fences do not exceed the FCC ET Docket allowed levels for General Population/Uncontrolled Exposure. Except for the building roof tops, areas requiring ladder or climbing access, including the monopoles, were not measured. When entering areas not measured and climbing on the monopoles, workers should monitor fields and/or wear personal monitors and reduce power or shut down the appropriate transmitters as necessary to limit exposure to less than allowed Occupational/Controlled levels. Access to areas not measured is limited to those who have received awareness training and can exercise control over their exposure. 2. Notice signs, as required, are placed by the RF equipment rooms except for the sites at: 929 San Pablo - T-Mobile at Town Centre 423 San Pablo Ave - Verizon Golden Gate Fields - Verizon These equipment rooms shall be posted with a standard Notice sign. The area past these signs may be accessed by authorized personnel only, inform all entering that awareness training is required. The access doors shall remain locked when the area inside is not occupied by authorized personnel. 3. Caution signs, as required, are posted on the monopoles and towers except for the site at: Golden Gate Fields - Verizon Sign not maintained, replace. MPE levels for Occupational/Controlled may be exceeded in these areas. These areas should only be accessed by authorized personnel who have received awareness training and have the knowledge and equipment needed to reduce their exposure to levels below the Occupational/Controlled MPE. 4. The following exposure mitigation work procedures are recommended for those working on towers, other antenna supporting structures or building roof tops with antennas. Confirm all having access received awareness training within the last 12 months. Workers must be fully aware of the potential for exposure and must be able to exercise control over their exposure. Page 5

6 All having access shall assume antennas are active and stay back the distance noted on the signs posted at the site or, if signs are missing, a minimum of 25 feet. Provide workers in the areas of the antennas with personal monitors and the training needed to use them properly. If the worker receives an alert warning from the personal monitor, he/she shall carefully withdraw from the area of concern until the transmitter(s) of concern is/are disabled or appropriately reduced in operating power and using a lock-out tag-out device. Workers should always maintain a safe distance from exposed element antennas to avoid receiving RF burns. Workers should be aware of damaged waveguide, transmission line and loose fittings since a leak may not be detected by the personal monitor and can be harmful. If a damaged waveguide, transmission line or loose fittings are suspected, or confirmed, the associated transmitters should be disabled until repairs are completed. Never look into an active waveguide or antenna feed. Maintain a minimum distance of 5' from active microwave antenna feeds or stay behind the dish. Workers shall inform their supervisor if they have a medical implant or device. Workers shall report sensation of heating, RF burns, shock or suspected overexposure to their supervisor. Workers shall be informed of any changes at the site that may require changes or additions to the site procedures. 5. If changes are made to antennas or RF transmitter equipment the field measurements should be repeated to verify the site(s) are still in compliance with the FCC standard. Page 6

7 TABLES, PHOTOGRAPHS AND FIGURES Page 7

8 TABLE ONE and FIGURE 1 FCC ET Docket Limits for Maximum Permissible Exposure (MPE) Page 8

9 Table 1. Limits for Maximum Permissible Exposure (MPE) (A) Limits for Occupational/Controlled Exposure Frequency Electric Field Magnetic Field Range Strength Strength Power Density Averaging Time (MHZ) (V/m) (A/m) 2 (mw/cm ) (minutes) (100)* /f 4.89/f 2 (900/f )* f/ , f = frequency in MHZ * = Plane-wave equivalent power density (B) Limits for General Population/Uncontrolled Exposure Frequency Electric Field Magnetic Field Range Strength Strength Power Density Averaging Time (MHZ) (V/m) (A/m) 2 (mw/cm ) (minutes) (100)* /f 2.19/f 2 (180/f )* f/ , f = frequency in MHZ * = Plane-wave equivalent power density Page 9

10 NOTE 1 TO TABLE 1: Occupational/controlled limits apply in situations in which persons are exposed as a consequence of their employment provided those persons are fully aware of the potential for exposure and can exercise control over their exposure. Limits for occupational/controlled exposure also apply in situations when an individual is transient through a location where occupational/controlled limits apply provided he or she is made aware of the potential for exposure. NOTE 2 TO TABLE 1: General population/uncontrolled exposures apply in situations in which the general public may be exposed, or in which persons that are exposed as a consequence of their employment may not be fully aware of the potential for exposure or can not exercise control over their exposure. Page 10

11 TABLE TWO Test Equipment Used During the Project Page 11

12 Equipment Model Number Serial Number Notes Narda Survey Meter Narda Shaped Probe FCC regulation shaped 0.5% to 300% of Controlled standard Measurement Uncertainty: Includes wide band frequency response ±2.0 db, ellipse ratio ±0.75dB, calibration uncertainty ±0.5dB. Page 12

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14 TABLE THREE Data Points vs. Percent of Standard Page 14

15 Data Point vs. Percent of Standard (minimum meter sensitivity 0.5% of Occupational/Controlled) 1600 Posen (SMCHS) Data Point/ Ref. Point Readings as % of Standard Occupational/Controlled Readings as % of Standard General Population/Uncontrolled Spatial Averaged Peak ** Spatial Averaged Peak ** DP 1 DP 2 Roof Roof **Partial-Body SAR allowance is 20 times the Whole-Body SAR allowance. Page 15

16 PHOTOGRAPHS Page 16

17 929 San Pablo - T-Mobile at Town Centre 423 San Pablo Ave - Verizon Notice sign Notice sign Page 17

18 Golden Gate Fields - Verizon Golden Gate Fields - Verizon Notice sign Caution sign Page 18

19 ATTACHMENTS Page 19

20 ATTACHMENT A Definitions These definitions are taken from: ANSI C Communications Standard Dictionary by Martin H. Weik Page 20

21 DEFINITIONS Antenna- a transducer that converts electrical energy from a transmitter to electromagnetic waves in free space, or from free space to a receiver. Antenna Gain- vertical gain is caused by compressing the vertical plane pattern of the antenna into a narrower beamwidth. The net effect is to focus the antenna s energy toward the horizon at the expense of the upper and lower quadrants. Antenna system- antenna, coaxial cable, transmitter combiner, receiver multicoupler and any and all filtering and protective devices. Band- the frequency spectrum between two defined limits. db- Decibel, a gain or attenuation factor measured as 10 times the logarithm to the base 10 of a power ratio, or 20 times the logarithm to the base 10 of the voltage or current ratio. dbi- a standard reference level used for the measurement of antenna gain relative to an isotropic source. dbd- a standard reference level used for the measurement of antenna gain relative to a half-wave dipole which has directivity and power gain of 2.15 db over isotropic. Electric field- the effect produced by the existence of an electric charge in the volume of space that surrounds it. Electromagnetic radiation- the field that is made up of oscillating and interacting electric and magnetic fields. Electromagnetic wave- the effect obtained when a time-varying electric field and a time-varying magnetic field interact, causing electric and magnetic energy to be propagated in a direction that is dependent upon the spatial relationship of the two interacting fields that are interchanging their energies. ERP- effective radiated power, the power supplied to an antenna multiplied by the directive gain (power gain) of the antenna in a given direction relative to a half-wave dipole antenna.. EIRP- effective radiated power, the power supplied to an antenna multiplied by the directive gain (power gain) of the antenna in a given direction relative to an isotropic antenna. Free space loss- the signal attenuation that would result if all scattering, reflecting, diffusing, absorbing and diffracting influences were removed so as to have no effect on propagation. Free space loss is primarily caused by beam divergence. Isotropic- radiation of equal power density in all directions. Isotropic sources do not exist physically, but they are a convenient reference source. Page 21

22 Magnetic field- a field that is created by an electric charge that is in motion. Maximum Permissible Exposure (MPE)- The RMS and peak electric and magnetic field strengths, their squares, or the plane-wave equivalent power densities associated with these fields to which a person may be exposed without harmful effect and with an acceptable safety factor. MHZ- megahertz, a unit of frequency, one million cycles per second. Nonionizing- does not produce charged particles. NIER- Nonionizing Electromagnetic Radiation. Any electromagnetic radiation incapable of producing ions directly or indirectly. Microwaves and radiofrequency waves are nonionizing radiation. Omnidirectional Transmission- is transmitted in equal intensity or power density in all directions, or at least in a given plane such as the horizontal plane. Power Density (S)- Power per unit area normal to the direction of propagation, usually expressed in units of milliwatts per square centimeter (mw/cm²). RF- radio frequency, those frequencies of the electromagnetic spectrum that are associated with radio wave propagation. In the range of 3,000 cycles to 3,000,000 MHZ. Single point source- isotropic point source. Uncontrolled environment- locations where there is the exposure of individuals who have no knowledge or control of their exposure to NIER. Watt- equal to the power in a circuit in which one ampere flows across a potential difference of one volt. Wavelength- the length of a radio wave in the direction of propagation of the wave, between two successive points in the same phase of oscillation. Page 22

23 ATTACHMENT B Credentials of Accord Communications Page 23

24 ACCORD COMMUNICATIONS Peter Gruchawka - President Relevant Credentials Forty years professional experience in the land mobile communications industry. FCC General Radiotelephone Operator License ( # PG ) Qualified per Paragraph IV of FCC to conduct NIER compliance studies State of California Contractor s License ( # ) Theory and survey hazard training for radio frequency radiation. Loral - Hauppauge NY Relevant Specialties Provide proof of performance testing of telecommunication facilities. Conduct field and mathematical studies of NIER. Design and implement emergency communications systems. Design and construct communication sites and project management. Design antenna systems. Page 24