July 20, 2020
Clarification on requirements set forth in issue 1 of SPR-002
This notice clarifies some of the requirements set forth in SPR-002, issue 1, Supplementary Procedure for Assessing Compliance with RSS-102 Nerve Stimulation Exposure Limits, based on inquiries and testing reports received as part of the certification process.
1. Probe and test equipment (meter) frequency range
Based on SPR-002, the test equipment (meter) must be operable from 3 kHz to 10 MHz. Should a probe have a reduced frequency span, the use of multiple probes to ensure coverage of the full frequency range from 3 kHz to 10 MHz may be employed as stated in section 5.2.1 of SPR-002.
2. Characterization for frequency range reduction
To reduce the investigated frequency range to less than the full 3 kHz to 10 MHz span, the applicant must demonstrate that:
- the characteristics of the transmitter are known
- there are no emissions produced by the device under test (DUT) outside of the investigated frequency range as stated in section 5.2.1 of SPR-002.
The characterization is an analysis of the radiated emissions from the DUT over the entire frequency range from 3 kHz to 10 MHz. To ensure proper frequency range reduction, the applicant shall provide spectrum plot(s) over the entire frequency range of 3 kHz to 10 MHz demonstrating that there are no emissions outside the investigated or reduced frequency range.
3. Summation - single-axis probe
To satisfy the limits set forth in RSS-102 — Radio Frequency (RF) Exposure Compliance of Radiocommunication Apparatus (All Frequency Bands), the measurement summation must be performed over three axes, preferably with a 3-axis isotropic probe. Alternatively, the measurement may be performed with a single-axis probe where each orthogonal axis (i.e. x, y and z) is measured and collectively summed. All measurements performed with a single-axis probe shall use the method in section 18.104.22.168 of SPR-002 and demonstrate evidence of 3-axis measurement summation using equations (4) and/or (5), respectively.
4. Summation - multiple frequencies
The following section provides clarification on summation requirements for a DUT with multiple frequencies..
4.1 All frequencies included
All frequencies in the range of 3 kHz to 10 MHz shall be included in the assessment provided the field value is within 20 dB of the maximum level identified as stated in sections 22.214.171.124 (h) and 126.96.36.199 (h) of SPR-002.
4.2 Omitted frequencies
Devices with multiple frequency components and/or multiple antennas co-located in the measurement space with emissions that are less than 20 dB below the maximum level identified (-20 dBc) over the frequency range of 3 kHz to 10 MHz may be omitted from the assessment as stated in section 6.3 of SPR-002.
To justify the exclusion of a frequency, the applicant shall provide spectrum plot(s) over the entire frequency range of 3 kHz to 10 MHz demonstrating that emissions are less than 20 dB below the maximum level identified (-20 dBc).
4.3 Summation of measurements from multiple frequencies
To determine compliance with nerve stimulation limits:
- the contributions from multiple frequencies transmitted by the DUT must be combined using equations (2) and (3) as instructed in sections 188.8.131.52 (i) and 184.108.40.206 (i) of SPR-002
- the user shall provide evidence of the measurement summation and the results obtained shall be less than or equal to unity as indicated in section 6.2.2 of SPR-002.
5. ISED-recognized testing laboratory
All testing performed to demonstrate compliance with nerve stimulation (NS) limits set forth in SPR-002, shall be conducted by an ISED-recognized testing laboratory that has RSS-102 (NS) as part of their scope.
6. RSS-102 annex A - RF technical brief cover sheet
7. Nerve stimulation reporting
To demonstrate compliance with the nerve stimulation exposure requirements set forth in RSS-102 and SPR-002, an RF technical brief shall be provided for the assessment. Users shall measure and report both the E-field and H-field values along with the corresponding compliance distance as stated in section 6.6.1 of SPR-002.
8. Exemption limits from routine evaluation
The exemption limits from routine evaluation detailed in section 2.5 and annex C of RSS-102 do not apply to nerve stimulation. Applications for equipment certification subject to nerve stimulation requirements will not be accepted by ISED without a nerve stimulation evaluation.
If you have any questions or require additional guidance, use the General Inquiry form to contact ISED.