REVISIONS REV DESCRIPTION DATE APPROVED

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1 REVISIONS REV DESCRIPTION DATE APPROVED A Initial Report May 17, 2013 KAR B Issued report to correct typographical errors. May 31, 2013 KAR C Incorporation of University of Regina Comments September 9, 2013 KAR DRAWN CHECKED SMR Planetworks Consulting Corporation North Vancouver, BC, Canada SaskPower Sensus Electrical Meter Safety Code 6 Report Prepared for SaskPower THIS DOCUMENT HAS BEEN ELECTRONICALLY SIGNED WHEN STAMP IS VISIBLE. REFER TO THE ELECTRONIC VERSION FOR SIGNATURE AND DOCUMENT VERIFICATION. Measured By: Brad MacKenzie EIT Prepared by: Karl Reardon, P.Eng. Tel: kreardon@planetworks.ca Report date: September 9, 2013 SIZE DWG. NO. STC_AMI_LAB REV C SCALE: None PAGE 1 OF 15

2 1 SUMMARY SITE LOCATION/ DETAILS ATTESTATION SAFETY CODE 6 DEFINITIONS REVIEW OF FINDINGS, CONCLUSIONS AND REMEDIAL ACTIONS Meter Inventories Findings Next Steps and Required Remedial Actions MEASUREMENT PROCEDURE DESCRIPTION OF PROCEDURE USED TEST EQUIPMENT DESCRIPTION NBM 550 CALIBRATION CERTIFICATE EC5091 CALIBRATION CERTIFICATE TRAFFIC GENERATION FIELD PROBE LOG FILES SPECTRUM ANALYZER PLOTS SaskPower Sensus Electrical Meter 2 of 16 MAY 2013

3 Executive Summary Objective Approach Findings To certify the compliance of SaskPower s Smart electric (utilizing Sensus FlexNet Advanced Metering Infrastructure) against Canadian federal regulations as specified by Health Canada Safety Code 6. This report describes the test results for a single electrical meter. Planetworks, a telecommunication engineering consulting firm, has been contracted to conduct independent testing of SaskPower s Smart Meters. Planetworks uses a Narda Broadband Field Meter (NDM 550) with a shaped isotropic field probe, which is the most accurate field meter solution available for broadband radiofrequency (RF) exposure limit measurements. The testing environment has been constructed to be as realistic a representation of usage environment as possible. Although care was taken to ensure no other strong emitters of RF energy were present in the testing environment, it was not possible to eliminate the secondary sources of RF energy such as fluorescent lighting, electrical transformers, external Wi Fi hotspots, signals from cellular sites, broadcast sources, etc. Therefore, some level of background RF energy is included in all the measurement results. All testing has been conducted in conformance to procedures defined in Health Canada s Safety Code 6. At the operational frequencies of the Smart Meters, Safety Code 6 defines a maximum permissible power density of 6 W/m 2 (averaged over a 6 minute period) for uncontrolled areas (i.e. public areas). Using the relationship that 1 W/m 2 equals 100 W/cm 2, the Safety Code 6 permissible limit for 900 MHz emissions can be converted to 600 W/cm 2. All measurements were conducted over a 36 minute period which is sufficient to ensure that sufficient samples are obtained from the single Sensus meter. This timeframe exceeds Health Canada s requirement for a single 6 minute sample and permits 6 such 6 minute averages to be obtained and compared. 1. All test configurations resulted in measurements which are below the Health Canada Safety Code 6 limit for public areas (uncontrolled environments). 2. With the Sensus meter disabled a background level of between 0.02% and 0.085% of Health Canada Safety Code 6 limit for public areas (uncontrolled environments) was measured. 3. At 20 centimeter distance from the meter, the maximum average power density measured over a 36 minute period is 0.32% of Health Canada Safety Code 6 limit for public areas (uncontrolled environments). These tests were conducted using an absolute worst case transmission rate of 1 transmission per second. These measured values include the background radio frequency signals originating from other internal or external sources. 4. While maintaining the 20 centimeter distance to the meter, but decreasing transmission rates to 6 transmissions per minute and 1 transmission per minute maximum average power density of between 0.077% and 0.094% of Health Canada Safety Code 6 limit for public areas (uncontrolled environments) were recorded for both rates. It is noted that these measurements are statistically indistinguishable from the background RF signal levels from other sources. 5. At 100 centimeter distance from the meter, the maximum average power density measured over a 36 minute period is 0.091% of Health Canada Safety Code 6 limit for public areas (uncontrolled environments). These tests were conducted using an absolute worst case transmission rate of 1 SaskPower Sensus Electrical Meter 3 of 16 MAY 2013

4 transmission per second. These measured values include the background radio frequency signals originating from other internal or external sources. It is noted that these measurements are indistinguishable from the background RF signal levels from other sources. 6. While maintaining the 100 centimeter distance to the meter, but decreasing transmission rates to 6 transmissions per minute and 1 transmission per minute maximum average power density of between 0.036% and 0.091% of Health Canada Safety Code 6 limit for public areas (uncontrolled environments) were recorded for both rates. It is noted that these measurements are indistinguishable from the background RF signal levels from other sources. 7. Measurements were not recorded for distances of 300 centimeters, since at this distance the measured values for all test cases were indistinguishable from background levels. Spectrum analyzer tests shown that the Sensus meter signal levels are less that FM broadcast signal levels and other ambient signals. 8. The Narda Field Meter measures the cumulative emissions across a very wide frequency range and automatically applies measurements against the Health Canada Safety Code 6 limit appropriate for each frequency. While this approach provides a very accurate assessment of the percentage of Safety Code 6 limit attained, it is not possible to accurately convert this value into a power density due to the presence of background RF sources. However, if it is assumed that all measured emissions originated from the Smart Meter, during the test conducted at 20 centimeters distance, the minimum and maximum average measurements (0.32%) can be converted to a power density of 1.92 W/cm All of the above measurement results continue to remain below Safety Code 6 limits when a measurement uncertainty factor of 2.65 is applied to account for worst case signal reflections. SaskPower Sensus Electrical Meter 4 of 16 MAY 2013

5 1 Summary 1.1 Site Location/ Details Site Street Address Location of Antennas Not applicable A single Sensus electrical meters was tested in an office environment. Test Start April 18, 2013 Test Stop April 19, 2013 Site Plan Attch. n/a Antenna Photos Attch. n/a Site Photo Attch n/a Log Files Attch. Yes 1.2 Attestation I, Karl Reardon, a Professional Engineer registered in the Province of Saskatchewan, certify that, at the time of testing, the radio frequency field levels from a single Sensus Smart Meters complies with Health Canada regulations based on the specified documentation below: (HC Pub ) Limits of Human Exposure to Radio frequency Electromagnetic Energy in the Frequency Range from 3 khz to300 GHz Safety Code 6 (2009) (HC Pub ) Technical Guide for Interpretation and Compliance Assessment of Health Canada's Radio frequency Exposure Guidelines Measured Results Below Health Canada Safety Code 6 Exposure Limits for Uncontrolled Environments (General Public, not trained in radio frequency hazards, exposed to RF and Microwave emissions) Induced Currents are below HC SC 6 Requirements Signage Meets HC SC 6 Requirements Access to test location was controlled and logged Note: Lab Test Access restrictions not applicable Within Safe Limits Defined by Health Canada Yes N/A N/A Notes (1) The Sensus Smart Meter products being tested contain both a FlexNet radio as well as a Zigbee radio. Both radios are configured to transmit at the same frequency and both radios were enabled during testing. Due to the test setup, no transmissions would have been made from the Zigbee radio. This setup best represents the typical operation of the Smart Meter products. (2) The Narda probe was placed to ensure the path between the Sensus meter s antennas and the Narda Probe was un obstructed. This placement ensured maximum readings from the meter under test. (3) The Narda meter records cumulative RF emissions from all RF sources in the spectral range from 0.3 MHz to 50,000 MHz. Care was taken to ensure no significant RF sources were active in the room during the test. It should be noted that buildings typically contain many secondary RF sources such as fluorescent lighting, electrical transformers, motors, etc. Additionally, most populated areas contain many external RF sources that cannot be controlled, including Wi Fi hotspots, signals from cellular sites and devices, two way radio communication and broadcast sources. SaskPower Sensus Electrical Meter 5 of 16 MAY 2013

6 1.3 Safety Code 6 Definitions Prior to the 2009 dated release of the Health Canada Safety Code 6 specifications, the documentation defined exposure limits for "RF and occupationally exposed workers" and exposure limits for the "general public." The general public was defined as any individual who may be exposed to RF emissions and has no knowledge or training in radio technology. Consequently exposure limits for the general public are five times lower than that for the RF worker who must have adequate safety training to work with antenna systems. Challenges arose when defining "occupationally exposed workers." In the 2009 edition of the Safety Code 6 guidelines, Health Canada attempted to address the ambiguities in these definitions by categorizing sites as "controlled" and "uncontrolled" where "uncontrolled" replaced the definition for the general public. The following text is lifted from current Health Canada s Safety Code 6 documentation and defines controlled versus uncontrolled environments. Controlled and Uncontrolled Environments For the purpose of this code, controlled environments are defined as those where all of the following conditions are satisfied: (a) The RF field intensities in the controlled area have been adequately characterized by means of measurements, calculations or modeling (such as with the use of FDTD [finite difference time domain] software), (b) The exposure is incurred by persons who are aware of the potential for RF exposure and are cognizant of the intensity of the RF energy in their environment and, (c) The exposure is incurred by persons who are aware of the potential health risks associated with RF energy exposures and whom can control their risk using mitigation strategies. All situations that do not meet the specifications above are considered to be uncontrolled environments. Uncontrolled environments are defined as areas where either insufficient assessment of RF energy has been conducted or where persons who are allowed access to these areas have not received proper RF awareness training and have no means to assess or, if required, mitigate their exposure to RF energy. 1 1 Chapter 2, Maximum Exposure Limits, Limits of Human Exposure to Radiofrequency Electromagnetic Energy in the Frequency Range from 3 khz to 300 GHz, HC Pub.: SaskPower Sensus Electrical Meter 6 of 16 MAY 2013

7 Exposure limits for controlled and uncontrolled environments is defined by Health Canada in the following tables. Applying the exposure limits from these standards to SaskPower s Smart Meters which use a radio operating near 900 MHz the limits are: Uncontrolled Environments 6 Watts/meter squared (W/m 2 ) or 600 microwatts per square centimeter ( W/cm 2 ) Controlled Environments 30 W/m 2 or 3,000 W/cm 2 SaskPower Sensus Electrical Meter 7 of 16 MAY 2013

8 Conversion between W/m 2 and W/cm 2 is performed using the relationship that 1 W/m 2 equals 100 W/cm Review of Findings, Conclusions and Remedial Actions Planetworks conducted testing to Health Canada Safety Code 6 for a single Smart Meters Meter Inventories A single electrical meter was present in the test area. A meter inventory is seen below. Meter Type Subclass FlexNet Model FlexNet ID Serial Number Electrical 200A 240V 1Phase 3Wire 530X N Findings Testing showed that even in close proximity (20 centimeter) to a single Smart Meter, RF emissions from the meter is less than the limits imposed by Health Canada for the general public in uncontrolled environments. In summary, the following can be derived from the test data collected. In the table below it should be noted that a number of the test conditions result in measurements which are below 0.1% of the Uncontrolled Standard. At these very low levels the measurements are significantly impacted by external background signals, minor differences between measurement times, Narda meter uncertainty, and Narda meter noise floor. These factors result in what appears to be measurement anomalies, but are in fact expected variations based on tolerances for measurements taken with such low levels. Measured Percentage of Safety Code 6 Uncontrolled Limit Distance 60 Transmissions / Minute 6 Transmissions / Minute 1 Transmissions / Minute 20 cm 0.32% 0.08% 0.09% 100 cm 0.09% 0.09% 0.04% Measurement Uncertainty At this time, the Narda unit represents the most accurate broadband, cumulative field metering solution available for RF exposure limit measurements in operational environments. The average emissions measured are below a field strength of V/m, which is the lower limit rating of the Narda unit. At measurements below this level, the accuracy of the results may not be within the tolerance specified in the meter calibration certificate (Section 6) and the results obtained may also include internal noise generated by the Narda meter. It is therefore likely that the emissions from the Sensus Smart Meters are actually lower than those measured in this report. Changes in operational and test environment may cause a change in RF fields as a result of reflections. In the majority of environment these reflections are time varying and a therefore represented in the averages levels measured. In the event that these reflections are not time varying and the meter was placed at a minima, a factor of 2.56 would be applied. Applying the measurement uncertainty factor of 2.65 results in a maximum of 0.82% for the 20cm / 60 trans/minute case. SaskPower Sensus Electrical Meter 8 of 16 MAY 2013

9 1.4.4 Next Steps and Required Remedial Actions No remedial actions are required. SaskPower Sensus Electrical Meter 9 of 16 MAY 2013

10 2 Measurement Procedure 2.1 Description of Procedure Used Measurements used to determine conformity with the limits specified by Safety Code 6 are performed with the field sensor (probe) placed approximately twenty centimetres away from any object or person with measurements averaged over six minutes as per SC 6. The Narda SC 6 test meter was allowed to log measurements undisrupted for the duration of the test. 2.2 Test Equipment Description Meter Narda NBM 550 Serial #: B 0670 Calibration due: Probe Narda EC5091 Serial #: Calibration due: The following list of parameters was downloaded from the meter and was used as the basis of the testing: Device Product Name NBM 550 Device Serial Number B 0670 Device Cal Due Date 4/21/2013 Probe Product Name EC5091 Probe Serial Number Probe Cal Due Date 4/25/2013 Probe Field Type E Probe Connection Type C Probe Lower Frequency Limit A 300 khz Probe Upper Frequency Limit A 50 GHz Probe Lower Frequency Limit B 300 khz Probe Upper Frequency Limit B 50 GHz Probe Emin A V/m Probe Emax A V/m Probe Emin B V/m Probe Emax B V/m Shaped Probe YES Standard ID 5 Standard Name Canada,occ Apply Standard ON Frequency 2.45 GHz Apply Correction Frequency OFF Eref_E(f) V/m Eref_H(f) V/m Combi Probe Use E Unit V/m SaskPower Sensus Electrical Meter 10 of 16 MAY 2013

11 Results Format FIXED 3 NBM 550 Calibration Certificate 4 EC5091 Calibration Certificate SaskPower Sensus Electrical Meter 11 of 16 MAY 2013

12 5 Traffic Generation Transmissions from the Sensus electric meter were controlled and managed through the use of a Sensus USB Micro Transceiver managed through the use of the Sensus FlexNet Utility v beta. The USB Micro transceiver was located a sufficient distance from the test arrangement so as not to impact field strength measurements performed by the Narda meter. Traffic generation was initiated by transmitting pings to the meter at specified intervals of either 1 second, 10 seconds or 60 seconds. On receipt of the ping the electric meter transmits a s long response. Receipt of responses were verified via the FlexNet Utiliy screen and log files. Cumulative meter transmission time for each of the 36 minute tests was as follows: 1 Second Interval Test: 54 seconds total transmission time 10 Second Interval Test: 5.4 seconds total transmission time 60 second Interval Test: 0.9 seconds total transmission time. 6 Field Probe Log Files The following table presents the average E Field as a percentage of Health Canada s Safety Code 6 limit for uncontrolled environments. All measurements are average over a 6 minute exposure time. Measurements are shown for: Background: No meter transmitting 20 cm Probe Distance with a Transmission Interval of 1 second 20 cm Probe Distance with a Transmission Interval of 10 seconds 20 cm Probe Distance with a Transmission Interval of 60 seconds 100 cm Probe Distance with a Transmission Interval of 1 second 100 cm Probe Distance with a Transmission Interval of 10 seconds 100 cm Probe Distance with a Transmission Interval of 60 seconds 6 Minute Sample # Average (E Field) [% STD] Background 20cm 1s 20cm 10s 20 cm 60s 100 cm 1s 100cm 10s 100cm 60s SaskPower Sensus Electrical Meter 12 of 16 MAY 2013

13 7 Spectrum Analyzer Plots In addition to the above tests conducted with the Nada NBM550 meter and shaped probe, additional measurements were conducted using a Rohde and Schwarz FSH8 spectrum analyzer coupled to a Mobile Mark antenna, model number SMW-UMB-1HDHE2HF. This antenna has a gain on 2 dbi across the band 800MHz to 2700 MHz. Measurements were conducted at a distance of 20 cm, 100 cm, and 300 cm from a single electrical Sensus meter. Transmissions from the gas Sensus meter occurred too infrequently to capture on a spectrum analyzer and this meter was therefore not tested further.. It should be noted that all measurements using the spectrum analyzer show the maximum signal level, and that this signal is only present for a very small portion of the time. Analysis of the waveforms shows that a typical transmission has a duration of less than s. 20 cm Measurement Distance SaskPower Sensus Electrical Meter 13 of 16 MAY 2013

14 The meter transmission is shown in the center of the screenshot as is identified by Marker 1 (M1). The other peaks captured by the spectrum analyzer are signals within the band which are being transmitted by external devices which are not part of the test configuration (i.e. background signals). At 20 cm this meter signal has a peak level of -20 dbm, or 0.01 Watts. The power of the signal, as measured across a 2 MHz bandwidth was dbm, or Watts. This measurement relates to an instantaneous power density level of 0.94 W/m 2. Again it is noted that this level is only present for s during any transmission. The results from this test can be compared to the tests with the Narda meter. At a rate of 1 transmission per second the cumulative transmission time is s every second. Using the peak, instantaneous power density of 0.94 W/m 2, and a cumulative transmission time of s, results in an average power density of W/m 2. This level equates to 0.39% of the Safety Code 6 limit for uncontrolled environments. It is noted that this is the within tolerances (~+/- 3 db) to the measurements performed with the Narda NBM550 meter and EC5091 shaped probe. 100 cm Measurement Distance SaskPower Sensus Electrical Meter 14 of 16 MAY 2013

15 The meter transmission is shown in the center of the screenshot as is identified by Marker 1 (M1). At 100 cm distance this signal has a peak level of dbm, or Watts. The power of the signal, as measured across a 2 MHz bandwidth was dbm, or Watts. This measurement relates to an instantaneous power density level of 0.03 W/m 2. Again it is noted that this level is only present for s during any transmission. 300 cm Measurement Distance The meter transmission is shown in the center of the screenshot as is identified by Marker 1 (M1). At 300 cm distance this signal has a peak level of dbm, or Watts. The power of the signal, as measured across a 2 MHz bandwidth was dbm, or Watts. This measurement relates to an instantaneous power density level of W/m 2. Again it is noted that this level is only present for s during any transmission. Comparison with other Background Signals The following spectrum analyzer screen capture shows the Sensus meter signal (at 300 cm distance) as compared to other RF signals which may be present in typical customer environment. SaskPower Sensus Electrical Meter 15 of 16 MAY 2013

16 The capture above shows an expanded frequency range, which the Sensus meter indicated by Marker 2 (M2). Broadcast FM transmitters, approximately 6.6 km distant from the indoor measurement location are shown by Marker 1 (M1), with a typical residential Wi-Fi signal shown by Marker 3 (M3). The Wi-Fi transmitter was approximately 450 cm from the measurement location. As can be seen the peak Sensus meter levels are 10 times lower than FM broadcast radios present inside a building 6.6 km distant from the FM broadcast site. The meter levels are approximately 5 times lower than those found near a standard residential Wi-Fi access point. SaskPower Sensus Electrical Meter 16 of 16 MAY 2013