Am Radio Rf Energy Assessment
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OAKVILLE GREEN DEVELOPMENT – AM RADIO RF ENERGY ASSESSMENT Stantec was asked to conduct a review of the Impact documents which were prepared by Whiteoaks consultants. The documents were commissioned to highlight impact of local land use proposals on the operation of the two existing AM radio stations, CJYE and CJMR. May 8, 2019 Prepared for: Kenneth Poon, P.Eng. LEED AP; Civil Engineering Discipline Lead - Community Development Prepared by: Enzo D’Agostini P. Eng. Senior Telecommunications Engineer Table of Contents 1.0 EXECUTIVE SUMMARY ....................................................................................................... I 2.0 BACKGROUND ................................................................................................................ 2.1 3.0 SAFETY CODE 6 – EXPOSURE LIMITS .......................................................................... 3.2 3.1 SPECIFIC ABSORPTION RATE LIMITS (SAR) (100 KHZ–6 GHZ) ................................... 3.3 4.0 BASELINE PERSPECTIVE AND DISCUSSION ............................................................... 4.5 4.1 REGULATORY CONSIDERATIONS (ISED) ..................................................................... 4.5 4.1.1 Radio Frequency Exposure Limits ............................................................... 4.6 5.0 INITIAL CONDITIONS ...................................................................................................... 5.7 5.1 TECHNICAL DISCUSSION AND CONSIDERATIONS ...................................................... 5.8 5.1.1 Free Space Path Loss, Attenuation of Electromagnetic Radio Waves ......... 5.9 5.1.2 Typical Directive Antenna Pattern Characteristics ..................................... 5.12 5.1.3 Internal Electrical Field Strength ................................................................ 5.13 5.1.4 Signal Strength Calculations ..................................................................... 5.14 5.1.5 Induced and Contact Currents ................................................................... 5.17 5.1.6 Magnetic Field Strength ............................................................................ 5.17 5.1.7 Re-Radiation Concerns ............................................................................. 5.18 5.1.8 Building Heights ........................................................................................ 5.19 6.0 REFERENCES ................................................................................................................ 6.20 LIST OF TABLES Table 1 Key Observations and Conclusions ...................................................................................... ii Table 2 Safety Code 6 - Internal Electric Field Strength Basic Restrictions (3 kHz-10 MHz) ......... 3.4 Table 3 Safety Code 6 - Specific Absorption Rate Basic Restrictions (100 kHz-6 GHz) ................ 3.4 Table 4 Safety Code 6 - Electric Field Strength Reference Levels ................................................ 3.5 Table 5 Safety Code 6 - Magnetic Field Strength Reference Levels .............................................. 3.5 Table 6 Free Space Path Loss Estimates ..................................................................................... 5.9 Table 7 Location Prediction of Exposure Contours for AM Antenna Systems .............................. 5.18 LIST OF FIGURES Figure 1 Free Space Path Loss Estimates .................................................................................. 5.10 Figure 2 Distance circle to Eastern edge of proposed development site ..................................... 5.10 Figure 3 Distance circle to Western edge (Third Line) of the proposed development site ............ 5.10 Figure 4 Proposed Plot Plan and site development ..................................................................... 5.11 Figure 5 Glenn Abbey Subdivision and other Buildings in close proximity of tower site ............... 5.11 Figure 6 Typical 2D Directive Antenna Power Pattern13 and CJMR/CJYE patterns1 ................... 5.12 Figure 7 Proof of Performance for CJMR and CJYE (Formerly CHWO) Radiation Patterns (1992) 1 .......................................................................................................................... 5.13 Figure 8 Estimated Signal Strength (dBuV/m and V/m) for CJMR and CJYE signals at the Oakville Green Development Site using Free Space Loss Estimates............................ 5.15 Figure 9 Estimated Signal Strength (dBuV/m and V/m) for CJMR and CJYE signals at the Oakville Green Development Site considering combined effect of co-sited non TDM operation. ..................................................................................................................... 5.16 LIST OF APPENDICES APPENDIX A ................................................................................................................................ A.1 A.1 Safety Code 6, 2015 .......................................................................................................... A.1 APPENDIX B ................................................................................................................................ B.1 A.2 EllisDon Letter, April 18, 2019 ........................................................................................... B.1 APPENDIX C ................................................................................................................................ C.1 A.3 Preliminary Proposed Building Elevations ......................................................................... C.1 APPENDIX D ................................................................................................................................ D.1 A.4 Toronto AM Stations .......................................................................................................... D.1 1.0 EXECUTIVE SUMMARY Stantec was asked to provide a professional opinion on concerns raised by Whiteoaks consultants in a document package entitled “Compressed_O'Connor MacLeod Hanna Comments_Redacted” 1. Within this document package there are numerous technical reports completed by Lawrence Behr Associates, Lehman and Associates and M.A. Tilston Engineering as well as a number of letters from private and public entities in support of the concerns raised by O’Connor MacLeod Hanna LLP. The review of the document package included reports which highlighted concerns from human safety due to the potential for high levels of RF Energy predicted to be present at the proposed Oakville Green Development site. The reports also included in-depth calculations and modelling of various scenarios to show that the presence of the proposed four (4) fifteen (15) storey buildings at the site and their construction could have significant negative impact to the two (2) radio station’s licensed antenna radiation patterns. Various scenarios using different construction crane heights at close proximity to the tower site were presented to model the potential distortion to the licensed radiation contours. The technical modelling, calculations and mathematical assessments in the report were completed using competent Electrical Engineering, valid antenna fundamentals knowledge and sound practices. There were however statements and calculations which were made out of context to raise concerns to a higher level. Specifically, that the investigated developments could introduce long term negative impact to the radio stations. The antenna array radiation pattern technical modelling was based on a different development proposal, “Martillac, Graydon-Banning and Oakville Green Life Sciences and Technology District.” 2 which was modelled to have residential components and tall structures within a few hundred meters of the Tower site. The impact of the concluding statements regarding the Martillac, Graydon-Banning development are very different than those which would apply in the Oakville Green Development proposal due to the close proximity to the tower site. The modelling conclusions on the radiation pattern distortion caused has no direct relevance to the Oakville Green Development case. The models would need to be redone using appropriate distances and pertinent parameters based on detailed architectural plans for the Oakville Green Development and the radio station’s latest Proof of Performance submissions. There are sections in the document addressing re-radiation, building heights and contact currents by M.A. Tilston Engineering which go back to 1993. The modelling and conclusions in those sections are technically accurate but overly conservative given the latest RF energy limits in Safety Code 6. The modelling was done for other proposed developments and not specifically for the Oakville Green Development project. i 1 - Compressed_O'Connor MacLeod Hanna Comments_Redacted, dated March 14, 2019 2 - Martillac, Graydon-Banning and Oakville Green Life Sciences and Technology District, extracted from Compressed_O'Connor MacLeod Hanna Comments_Redacted 3 – Safety Code 6 (2015); Limits of Human Exposure to Radiofrequency Electromagnetic Energy in the Frequency Range From 3 Khz TO 300 Ghz 4 – Lawrence Behr Associates extract from Compressed_O'Connor MacLeod Hanna Comments_Redacted 5 - TN-329 Technical Note; Safety Code 6 (SC6) Measurement Procedures (Uncontrolled Environment) 6 - TN-261, Issue 3, Safety Code 6 (SC6) Radio Frequency Exposure Evaluation Template (Uncontrolled Environment Exposure Limits), replaces TN- 261, Issue 2, published in December 2012. 7 - Federal Communications Commission