ANSI ACCREDITED STANDARDS COMMITTEE C63

ELECTROMAGNETIC COMPATIBILITY

SUBCOMMITTEE 8 – MEDICAL DEVICES AND EMC

 

Minutes

Tuesday – 14 March 2006

IEEE Headquarters – New Jersey

 

1    Opening and Self-Introductions

 

Members Present                                                      Affiliation

 

Matthew Bakke                                                            Gallaudet University

Stephen Berger                                                 TEM Consulting

Bob DeLisi                                                                   UL

Gerard Hayes                                                               Sony Ericsson

Don Heirman                                                                Don Heirman Consultants

George Hirvela                                                 Cingular

Bob Hofmann                                                               Hofmann EMC Engineering

Dan Hoolihan                                                               Hoolihan EMC Consulting

William Hurst                                                                FCC

Bob Jenkins                                                                  Welch Allyn     

Victor Kuczynski                                                          Vican Electronics

Harry Levitt                                                                  Hearing Loss Association

Dheena Moongilan                                                        Lucent

Joe Morrissey                                                               Motorola

Werner Schaefer                                                          Cisco

Jeff Silberberg                                                              FDA

Jim Turner                                                                    ATIS

Steve Whitesell                                                 Telecommunications Industry Assoc.

Al Wieczorek                                                               Motorola

Dave Zimmerman                                                         TUV America

 

 

Guests                                                                                    Affiliation

 

Poul Andersen                                                              SAE

Colin Brench                                                                HP

Kendra Green                                                              Samsung Telecom America

Ed Hare                                                                       American Radio Relay League

Warren Kesselman                                                       Independent

Richard Worley                                                            Dell

 

Al Wieczorek asked to confirm a quorum. It was confirmed by the chair that 17 members were present out of a total of 31 members so a quorum was present.

 

2    Review and Adoption of Agenda

 

The DRAFT Agenda was reviewed and adopted. See Attachment 1.

 

3.  Review and Adoption of Minutes of Previous Meeting

 

Jeff Silberberg Moved to approve the Draft Minutes of the September 28, 2005 meeting.  The Motion was seconded and approved by the Subcommittee.

 

4.   Working Group Reports

 

4.1  WG#1 – Jeff Silberberg - C63.18

 

Working Group 1 is developing the Second Edition of C63.18. Jeff Silberberg, the working group chair, reported that progress continues at a slow rate.

 

The Second Edition will use a field-strength meter as the principal instrument for measuring fields from cellular sources. The working group has requested information from Dave Baron of ETS-Lindgren, relative to measurement of  peak field-strength (e.g., from cell phones) with field strength sensors. It was pointed out by Steve Berger that there is an excellent article on power probe sensors in the latest issue of Evaluation Engineering.

 

4.2  WG#2 – Bob DeLisi – C63.21

 

Bob DeLisi from UL is chairing this group and looking for new members.  Bob gave a brief review of the history of the project Jeff Silberberg accepted an action item to recruit members from the FDA for the Working Group.

 

4.3  WG#3 – Steve Berger – C63.19

 

Steve Berger reviewed the history of C63.19 and also reported on the recent progress of this working group. Two meetings of the Working Group have been held in the last two months; both meetings were held at the FCC Lab in Columbia, Maryland and were attended by approximately 25 people.

 

A protracted discussion took place about the latest Draft Amendment of the standard. Concerns were expressed by ATIS on some of the wording implemented in the latest proposed amendment.

 

 

 

Steve Berger proposed a Motion to “Recommend to the Main C63 Committee to adopt the amendment including two issues recently added through electronic mail.”

The Motion was seconded. After extensive discussion, some members had trouble with the wording of several sections of the amendment.

 

It was agreed to attempt to resolve the wording issues with the Amendment during the meeting. A subgroup of people worked in real time to make wording changes. Agreement was reached on new wording.

 

A Motion was then made by Steve Berger to amend the original Motion to include the wording changes for Step 10, Step 12, and clause 7.3.3. The Amendment was seconded and discussed.  The Motion to Amend the Original Motion was voted on and passed with 15 positive votes, no negative votes and 2 abstentions (Bill Hurst – FCC, Werner Schaefer – Cisco Systems).

 

The Amended Motion was then voted on by a Roll Call Vote and it was passed unanimously by the Subcommittee with 17 ayes, no negatives and 3 abstentions. The 17 ayes were Matthew Bakke, Stephen Berger, Bob DeLisi, Gerard Hayes, Don Heirman, George Hirvela, Bob Hofmann, Dan Hoolihan, Bob Jenkins, Victor Kuczynski, Harry Levitt, Joe Morrissey, Jeff Silberberg, Jim Turner, Steve Whitesell, Al Wieczorek, and Dave Zimmerman. The three abstentions were Bill Hurst – FCC, Werner Schaefer – Cisco Systems, and Dheena Moongilan – Lucent Technologies.

 

Stephen Berger provided a file listing the complete set of changes approved, “C6319 - Proposed Amendment - 060314.pdf”.  See Annex to these minutes for a complete listing of the changes approved for the amendment.

 

 

 

 

 

5        Unfinished Business

 

Due to a lack of time, no discussion was held of Unfinished Business.

 

5.1    IEC SC62A Maintenance Team 23 – Jeff Silberberg

IEC SC62A MT23 Report for C63 SC8 Meeting March 2006

 

 

·        Meeting 7-10 February, Fort Lauderdale, Florida

·        Third edition of IEC 60601-1, basic safety and essential performance of medical electrical equipment and medical electrical systems, has been approved and published

·        Draft third edition of IEC 60601-1-2 circulated for ballot

o       IEC 62A/522/CDV

o       Editorial changes only – alignment with third edition of IEC 60601-1

o       Ballot closes 7 July

·        Plans for fourth edition of IEC 60601-1-2 circulated to SC62A for comment

o       Requirements for electromagnetic phenomena

o       IEC 62A/509/DC

o       Approved by SC62A

o       Comments received and addressed

o       Will be circulated shortly to National Committees as a maintenance cycle report

o       European members of MT23 will meet to further the work on requirements for electromagnetic environments other than general hospital

·        Standard for EMC (performance) of medical electrical equipment and systems in development

o       Will be proposed as a new work item

o       IEC SC62A MT23 will be proposed to do the work

o       Will be synchronized with the fourth edition of 60601-1-2

o       Will include a guide to the use of both 60601-1-2 and the new standard

·        Corrigendum to IEC 60601-1-2 Edition 2.1 (clarification that battery-operated medical equipment may be labeled as suitable for domestic establishments) delayed

o       MT23 plans to submit the corrections as comments on the CDV

·        Next meeting October 2006, Ottawa, Canada

 

 

5.2    AAMI/EMC Committee Report

No report

 

5.3     FDA Report – Jeff Silberberg

FDA Report for C63 SC8 Meeting March 2006

 

 

  1. Lab activities
    1. Continue work with TSA on medical device EMC with security systems, metal detectors
    2. Continue development of metal detector simulator for medical device immunity testing
    3. Continue lab project to investigate medical devices and wireless technology (Bluetooth, 802.11 b) EMC and data integrity concerns
    4. MRI implant heating computational methods and lab testing with ASTM group

 

  1. Standards activities
    1. C63: C63.19 revision, editing C63.16
    2. IEC SC62A MT 23
    3. Revision of supplementary information pages for IEC and ANSI/AAMI/IEC 60601-1-2 posted on CDRH website

                                                               i.      Recognition of Amendment 1

                                                             ii.      Provide evidence of meeting the labeling requirements

                                                            iii.      Transition to Amendment 1 / Ed. 2.1, withdrawal of Ed. 2 without A1

                                                           iv.      Presenting on IEC 60601-1-2 at AAMI conference on third ed. 60601-1

·        22-24 May

    1. Work in IEEE 1073/ISO TC 215 Wireless technology deployment: information and guidance
    2. ISO TC 150 SC on implanted infusion pumps, implanted neurostimulators.

                                                               i.      Method to create 150 A/m (level suggested in ISO 14708-1) completed

    1. ISO TC 173 SC 1 on ISO 7176 wheelchair standards
    2. AAMI EMC committee revision of TIR 18
    3. Participating in work group on test methods for 802.11 equipment

 

  1. CDRH outreach
    1. CDRH guidance for wireless technology in and around medical devices soon to be circulated for comment

                                                               i.      Concerns for:

·        performance of wireless functions

·        wireless coexistence

·        wireless quality of service

·        integrity of data transmitted wirelessly

·        security of data transmitted wirelessly and wireless network access

·        EMC

    1. Presenting on wireless in and around medical devices at AAMI Conference and Expo, June 2006
    2. Coordination and meeting with FCC re: medical device concerns

                                                               i.      Hearing aids

                                                             ii.      FCC initiative on wireless medical technology and expansion of the Medical Implant Communications Service (MICS – for implants)

                                                            iii.      Medical telemetry, including WMTS

                                                           iv.      BPL

                                                             v.      Approvals

 

 

 

5.4      Mobile Healthcare Alliance (MoHCA) Report

No report.

      

 

6        New Business

 

It was moved by Steve Berger to nominate Joe Morrissey as Vice-Chair of Subcommittee 8. The Motion was seconded and discussed. The Motion was approved with one abstention.

 

7        Next Meeting

The next meeting will be Wednesday, October 25th, 2006.

 

 

 


ANNEX

 

Draft Language For:

 

2006 Amendment
to
ANSI C63.19-2006
(final draft 3.12)

 

 


Overview

 

This document provides the proposed language addressing the six points of the PINS to develop an amendment to ANSI C3.19-2006.  The scope of this effort, as listed in the PINS is:

 

“The following sections will be addressed in the currently published standard C63.19:

 

a)       Change the magnetic measurement orientations from Axial and two radial to two measurements in one plane (reference Section 6.3, and 7.3.3, Annex A-3)

b)       Determine the signal strength(s) for the new T-coil measurement orientations (Section 7.3.1)

c)       Revise the Signal to Noise range in table 7.7

d)       Decouple the overall RF measurement on the mobile from limiting the rating of the T-coil measurement

e)       Change the RF measurement position from bottom of probe to the center of element and change to test distance from 1 cm to 1.5 cm  (reference Section 4.4, and Annex A-2)

f)        Incorporate TVC (test validation coil) tool into the Standard as an illustrative reference (similar to the dipole in the RF) in the T-coil Section 6 and the Annex (for development).  The TVC’s intended use is as a magnetic source for measurement setup validation, to be specified as an open-sourced device.  It is not intended as a substitute for Helmholtz coil calibration of the magnetic sensing probe.”


Table of Contents

Table of Contents. 3

Summary of changes. 5

Issue A – Reduction to 2 measurement orientations. 6

PINS scope. 6

Disposition. 6

Issue B – Required signal strength. 7

PINS scope. 7

Rational 7

Proposed Changes. 7

1st Change - Clause 7.3.1. 7

2nd Change – Clause 6.4.2 at the end of Ά 1. 8

3rd Change – Clause 7.3.2 captions for Figures 7-1 & 7-2. 8

Issue C – Revise table 7.7. 9

PINS scope. 9

Rational 9

Proposed Changes. 9

1st Change – Clause 7.3.3 Table 7.7. 9

2nd Change – Clause 6.3.1. 10

3rd Change – Clause 6.3.1 Step 2. 10

4th Change – Clause 6.3.4.1 Ά 2. 11

5th Change – Clause 6.3.4.2 Ά 1 sentence 2. 11

6th Change – Clause 6.2.1 Ά 2 sentences 2 & 3. 12

7th Change – Clause 6.4.1 Step 7. 12

Issue D – Decouple the RF from the T-Coil rating. 13

PINS scope. 13

Rational 13

Proposed Changes. 13

1st Change – Clause 6.3.1 last Ά. 13

2nd Change – Clause 7.3.3 Ά 3 & 4. 13

3rd Change – New Clause 7.3.3. 14

4th Change –Clause 4.4.1.2.1 Step 10. 14

5th Change –Clause 4.4.1.2.2 Step 12. 14

Issue E – Change the measurement distance. 16

PINS scope. 16

Rational 16

Proposed Changes. 16

1st Change – Section 4.3.2.1 Ά 4 Bullet 4. 16

2nd Change – Section 4.3.2.1.1 Ά 1 Bullet 3. 16

3rd Change – Section 4.3.2.1.3 Ά 1. 16

4th Change – Remove figure 4-2 & 4-3. 17

5th Change – Section 4.4 Ά 2 Line 6. 18

6th Change – Section 4.4 Ά 6 Line 1. 18

7th Change – Section 4.4 Ά 6 Line 5. 18

8th Change – Section 4.4 Ά 8 Bullet 2. 18

9th Change – Section 4.4.1.2.1 Step 2. 19

10th Change – Figure 4-6. 20

12th Change – Annex A.2 Bullet 4. 22

13th Change – Annex A.2 Figure A-2. 23

14th Change – Annex A.2.1 Figure A-3. 25

15th Change – Annex A.2.1 Figure A-4. 27

16th Change – Section 4.3.2.1 Table 4-2. 29

Issue F – Introduction of TVC.. 30

PINS scope. 30

Rational 30

Proposed Changes. 30

1st Change – Clause 2. 30

2nd Change – Clause 3.2. 30

3rd Change – Clause 6.1.1.2. 30

4th Change – Clause 6.3.1. 31

5th Change – Add new Clause D.19. 31


Summary of changes

 

Summary of Changes

Issue

Summary of Changes

 

a)       Change the magnetic measurement orientations from Axial and two radial to two measurements in one plane (reference Section 6.3, and 7.3.3, Annex A-3)

 

Rejected.  Retain current measurement orientations.

 

b)       Determine the signal strength(s) for the new T-coil measurement orientations (Section 7.3.1)

 

 

Adopt -18 dB A/m as the required signal level for all orientations.

 

c)       Revise the Signal to Noise range in table 7.7

 

 

Proposal adopted with 20 dB as the Category 2/3 boundary and other categories boundaries spaced 10 dB apart.  The use of AWF was removed from table 7-7. The use of A-weighting in measuring noise was retained.  Implementing wording is contained in this document.

 

 

d)      Decouple the overall RF measurement on the mobile from limiting the rating of the T-coil measurement

 

Proposal adopted to allow separation of RF (emission) M and T rating IF the M rating (the lower of M or T) is greater than or equal to M3. Such that a phone rated at M3 and T4 would be acceptable; where the T4 rating is for baseband only.

 

e)      Change the RF measurement position from bottom of probe to the center of element and change to test distance from 1 cm to 1.5 cm  (reference Section 4.4, and Annex A-2)

 

Adopt per specific wording changes recorded in this document.

 

f)        Incorporate TVC (test validation coil) tool into the Standard as an illustrative reference (similar to the dipole in the RF) in the T-coil Section 6 and the Annex (for development).  The TVC’s intended use is as a magnetic source for measurement setup validation, to be specified as an open-sourced device.  It is not intended as a substitute for Helmholtz coil calibration of the magnetic sensing probe.”

 

Adopt per specific wording changes recorded in this document.

 

 


Issue A – Reduction to 2 measurement orientations

PINS scope

“Change the magnetic measurement orientations from Axial and two radial to two measurements in one plane (reference Section 6.3, and 7.3.3, Annex A-3)”

Disposition

Proposed change was rejected.  The current wording of the standard remains.


Issue B – Required signal strength

PINS scope

“Determine the signal strength(s) for the new T-coil measurement orientations (Section 7.3.1)”

Rational

The WG decided to move to a single value on the T-Coil signal strength requirement.

Proposed Changes

1st Change - Clause 7.3.1

From:

 

7.3.1 T-Coil coupling field intensity

The T-Coil signal from the WD, when measured as specified in this standard, shall meet the parameters set forth below for the axial field intensity and the radial field intensities.  These measurements shall be made with the WD operating at a reference input level as defined in 6.3.2.1.

These levels are designed to be compatible with hearing aids that produce the same acoustic output level for either an acoustic input level of 65 dB SPL or a magnetic input level of –25 dB (A/m) (56.2 mA/m)[1] at either 1.0 or 1.6 kHz.  The hearing aid operational measurements are performed per ANSI S3.22.

7.3.1.1 Axial field intensity

The axial component of the magnetic field, directed along the measurement axis and located at the measurement plane, shall be ³ -13 dB (A/m) at 1 kHz, in 1/3 octave band filter.

7.3.1.2 Radial field intensity

The radial components of the magnetic field, as measured at the radial measurement points described in Section A.3[2], shall be ³ -18 dB (A/m) at 1 kHz, in 1/3 octave band filter.

 

To:

7.3.1 T-Coil coupling field intensity

The T-Coil signal for all orientations, when measured as specified in this standard, shall be ³ -18 dB (A/m) at 1 kHz, in a 1/3 octave band filter.  These measurements shall be made with the WD operating at a reference input level as defined in 6.3.2.1.

These levels are designed to be compatible with hearing aids that produce the same acoustic output level for either an acoustic input level of 65 dB SPL or a magnetic input level of –25 dB (A/m) (56.2 mA/m)[3] at either 1.0 or 1.6 kHz.  The hearing aid operational measurements are performed per ANSI S3.22.

2nd Change – Clause 6.4.2 at the end of Ά 1

From:

 

…. 7.3.1.1 for the axial reading and Section 7.3.1.2 for the radial readings.

To:


…. 7.3.1.

3rd Change – Clause 7.3.2 captions for Figures 7-1 & 7-2

From:

 

Figure 7 1 - Magnetic field frequency response for WDs with a field between -10 to -13 dB (A/m) at 1 kHz

 

Figure 7 2 - Magnetic field frequency response for WDs with a field that exceeds -10 dB(A/m) at 1 kHz

To:


Figure 7 1 - Magnetic field frequency response for WDs with a field ≤ -15 dB (A/m) at 1 kHz

 

Figure 7 2 - Magnetic field frequency response for WDs with a field that exceeds -15 dB(A/m) at 1 kHz

 


Issue C – Revise table 7.7

PINS scope

“Revise the Signal to Noise range in table 7.7”

Rational

Proposed Changes

1st Change – Clause 7.3.3 Table 7.7

From:

 

 

 

Category

Telephone parameters

WD signal quality

((signal + noise)-to-noise ratio in dB)

 

AWF = 0

AWF = -5

 

Category T1

-20 to -10 dB

-15 to -5 dB

 

Category T2

-10 to 0 dB

-5 to 5 dB

 

Category T3

0 to 10 dB

5 to 15 dB

 

Category T4

> 10 dB

>15 dB

 

 

 

(NOTE: For cases where it can be shown that the audio-band interference is not dominated by the RF pulse rate of the phone, AWF does not apply)

 

Table 01 – T-Coil signal quality categories

 

 

To:

 

 

Category

Telephone parameters

WD signal quality

(signal-to-noise ratio in dB)

 

 

Category T1

0 to 10 dB

Category T2

10 to 20 dB

Category T3

20 to 30 dB

Category T4

>30 dB

 

 

Table 02 – T-Coil signal quality categories

 

2nd Change – Clause 6.3.1

From:

 

The following summarizes the basic test flow:

 

To:


The following steps summarize the basic test flow for determining ABM1 and ABM2.  These steps assume that a sine wave or narrowband 1/3 octave signal can be used for the measurement of ABM1.  An alternate procedure yielding equivalent results utilizing a broadband excitation is described 6.4.

3rd Change – Clause 6.3.1 Step 2

From:

 

2. Set the reference drive level for the system with the maximum volume control setting or as specified by the manufacture. The drive level is set such that the reference input level defined in Section 6.3.2.1 is input to the base station simulator (or manufacturer’s  test mode equivalent) in the 1 kHz, 1/3 octave band. This drive level shall be used for the T-Coil signal test (ABM1 at f ). Either a sine wave at 1025 Hz or a voice-like signal as defined in Section 6.3.2 shall be used for the reference audio signal. If interference is found at 1025 Hz an alternate reference audio signal frequency may be used.  The same drive level will be used for the ABM1 frequency response measurements at each 1/3 octave band center frequency.

 

To:

 

2.   The drive level to the WD is set such that the reference input level defined in Section 6.3.2.1, Table 6-1 is input to the base station simulator (or manufacturer’s test mode equivalent) in the 1 kHz, 1/3 octave band. This drive level shall be used for the T-Coil signal test (ABM1) at f = 1 kHz. Either a sine wave at 1025 Hz or a voice-like signal, band-limited to the 1 kHz 1/3 octave, as defined in Section 6.3.2, shall be used for the reference audio signal. If interference is found at 1025 Hz an alternate nearby reference audio signal frequency may be used.[4] The same drive level will be used for the ABM1 frequency response measurements at each 1/3 octave band center frequency.  The WD volume control may be set at any level up to maximum, provided that a signal at any frequency at maximum modulation would not result in clipping or signal overload.

 

4th Change – Clause 6.3.4.1 Ά 2

From:

 

A 1025 Hz ± 10 Hz signal is recommended for sine test signals for the signal quality measurements.  For voice-like test signals, such as ITU P-50 artificial speech, the speech should be band-limited to the 1/3 octave centered at 1025 Hz….

 

…. The voltage required to produce this level (in dBm0) in the 1025 Hz band should be maintained for T-Coil signal measurements at all frequencies for the frequency response measurement.

 

To:

 

A 1025 Hz ± 10 Hz signal is recommended for sine test signals for the signal quality measurements.  For voice-like test signals, such as ITU P-50 artificial speech, the speech should be band-limited to the 1/3 octave centered at 1 kHz….

 

…. The same reference input level should be maintained for T-Coil signal measurements at all the other frequency bands for the frequency response measurement.

 

5th Change – Clause 6.3.4.2 Ά 1 sentence 2

From:

 

These measurements are made over the frequency range of 300 to 3000 Hz either in 1/3 octave bands centered at the ISO 266 R10 series of standard test frequencies or using a broadband signal that is subsequently analyzed for frequency content.

To:

 

These measurements are made over the frequency range of 300 to 3000 Hz either in 1/3 octave bands centered at the ISO 266 R10 series of standard test frequencies (as described in Section 6.3) or using a broadband signal that is subsequently analyzed for frequency content (as described in Section 6.4).

6th Change – Clause 6.2.1 Ά 2 sentences 2 & 3

From:

 

For the measurement of ABM1, this criterion applies in each 1/3 octave band over the specified voiceband.  For the measurement of ABM2, this criterion applies over the full measurement bandwidth. 

To:

 

For the measurement of ABM1 (Audio Band Magnetic signal – desired), this criterion applies in each 1/3 octave band over the specified voiceband.  For the measurement of ABM2 (Audio Band Magnetic signal – undesired), this criterion applies over the full measurement bandwidth.

 

7th Change – Clause 6.4.1 Step 7

From:

 

Measure desired plus undesired audio band magnetic signals, ABM1. 

To:

 

Measure audio band magnetic signal, ABM1.


Issue D – Decouple the RF from the T-Coil rating

PINS scope

“Decouple the overall RF measurement on the mobile from limiting the rating of the T-coil measurement”

Rational

The committee adopted a proposal to allow separation of RF (emission) M and T rating IF the M rating (the lower of M or T) is greater than or equal to M3. Such that a phone rated at M3 and T4 would be acceptable; where the T4 rating is for baseband only.

Proposed Changes

1st Change – Clause 6.3.1 last Ά

Remove the last paragraph:


To assure that the desired signal quality is provided, the RF field intensity at this measurement point must be at or below that required for the assigned category.  If the RF field intensity measurement at the location of the axial measurement of the desired signal (ABM1) was not recorded in the 5 x 5 cm scan taken per Section 4, then measure the RF field intensity at this location.  The RF field intensity at this location shall be at or below that required by the assigned category.

 

2nd Change – Clause 7.3.3 Ά 3 & 4

Remove Ά 3 & 4 from Clause 7.3.3:


A device is assessed beginning by determining the category of the RF environment in the area of the T-Coil source. The RF measurements made for the T-Coil evaluation are used to assign the category from Section 7.2, category T1 through T4. This establishes the RF environment presented by the WD to a hearing aid. If the device meets the additional requirements of this section it qualifies for the T designation, T1 through T4.

 

A device may be classified according to its audio coupling mode (M1 through M4), its T-Coil mode (T1 through T4), or both. Note: the T mode rating may be higher than the M mode rating.

 

3rd Change – New Clause 7.3.3

Add new Clause 7.3.3:


This section describes the relationship between the M rating, which is based on the RF emission tests performed in Clause 4 and the T rating, which is based on the T-Coil tests performed in Clause 6.

 

If the WD meets an M3 or M4 rating for both microphone and T-Coil mode, per Clause 4, it becomes a candidate for the T designation (see 7.3.4).  A WD is assessed by determining the category of the RF environment in the area of the T-Coil source. This establishes an acceptable RF environment presented by the WD to a hearing aid T-Coil.

 

4th Change –Clause 4.4.1.2.1 Step 10

From


Repeat steps 1-9 for the T-Coil mode assessment. The grid shall be shifted so that it is centered on the axial measurement point. Both the E- and H-field are measured for this grid. The category, per the tables in Section 7.2, obtained in step 8 for either E- or H-field determines the T category for the T-Coil mode assessment. Record the WD category rating.

 

To

 

For the T-Coil mode assessment repeat steps 1-9. The grid shall be shifted so that it is centered on the axial measurement point. Both the E- and H-field are measured for this grid. The category, per the tables in Section 7.2, obtained in step 8 for either E- or H-field determines the T category for the T-Coil mode assessment. Record the WD category rating.

 

If the axial measurement point is contained in a non-excluded sub-grid of the first scan, then a second scan is not necessary.  The first scan may be used for the microphone and T-Coil assessment. 

 

5th Change –Clause 4.4.1.2.2 Step 12

From


If the center of the T-Coil location is in a different position from the speaker opening, repeat steps 1-11 for the T-Coil mode assessment.  The grid shall be shifted so that it is centered on the axial measurement point.  Both the E and H-Field are measured for this grid.  The lowest category, per Table 7 4 or Table 7 5, obtained in step 11 for either E or H-Field determines the T category for the T-Coil assessment.  Record the WD category rating.

 

To

 

For the T-Coil mode assessment repeat steps 1-11. The grid shall be shifted so that it is centered on the axial measurement point. Both the E- and H-field are measured for this grid. The category, per the tables in Section 7.2, obtained in step 11 for either E- or H-field determines the T category for the T-Coil mode assessment. Record the WD category rating.

 

If the axial measurement point is contained in a non-excluded sub-grid of the first scan, then a second scan is not necessary.  The first scan may be used for the microphone and T-Coil assessment.  

 


Issue E – Change the measurement distance

PINS scope

“Change the RF measurement position from bottom of probe to the center of element and change to test distance from 1 cm to 1.5 cm  (reference Section 4.4, and Annex A-2)”

Rational

Proposed Changes

1st Change – Section 4.3.2.1 Ά 4 Bullet 4

From:

 

The probe-to-dipole separation, which is measured from top surface of the dipole to the nearest point on the probe sensor element, should be 10 mm, as shown in Figures C-3 and C‑4.

To:

 

The probe-to-dipole separation, which is measured from top surface of the dipole to the center point of the probe sensor element, should be 10 mm, as shown in Figures C-3 and C-4.

2nd Change – Section 4.3.2.1.1 Ά 1 Bullet 3

From:

 

the probes are 10 mm from the surface of the dipole elements.



To:

 

the center point of the probe elements are 10 mm from the surface of the dipole elements.

3rd Change – Section 4.3.2.1.3 Ά 1

From:

 

The probe is positioned over the illuminated dipole at 10 mm distance from the nearest point on the probe sensor element to the top surface (edge) of the dipole element as shown in Section C.4.3.  

To:

 

The probe is positioned over the illuminated dipole at 15 mm distance from the center point of the probe sensor element to the top surface (edge) of the dipole element as shown in Section C.4.3.

 

4th Change – Remove figure 4-2 & 4-3

From:

 

Figure 01 – Planar dipole setup

Figure 02 – Probe distance from planar dipole

 

To:

 

{Figures removed the distance is inaccurate and IEEE editors discourage the use of color photos.}

5th Change – Section 4.4 Ά 2 Line 6

From:

 

A measurement plane is located parallel to the reference plane and 10 mm from it, out from the phone.  The grid is located in the measurement plane.

 

To:

 

A measurement plane is located parallel to the reference plane and 15 mm from it, out from the phone.  The grid is located in the measurement plane.

6th Change – Section 4.4 Ά 6 Line 1

From:

 

The distance from the WD reference plane to the nearest point on the probe element shall be 1.0 cm.

 

To:

 

The distance from the WD reference plane to the center point of the probe element shall be 15 mm.

7th Change – Section 4.4 Ά 6 Line 5

From:

 

The physical body of the probe housing shall not be used when setting this 1.0 cm distance …

To:

 

The physical body of the probe housing shall not be used when setting this 15 mm distance …


8th Change – Section 4.4 Ά 8 Bullet 2

From:

 

The nearest point on the probe measurement element(s) shall be held 1.0 cm from the WD reference plane. The probe element is that portion of the probe that is designed to receive and sense the field being measured. The physical body of the probe housing shall not be used when setting this 1.0 cm distance as this would place the sensing elements at an indeterminate distance from the reference plane.

To:

 

The center point of the probe measurement element(s) shall be held 15 mm from the WD reference plane. The probe element is that portion of the probe that is designed to receive and sense the field being measured. The physical body of the probe housing shall not be used when setting this 15 mm distance as this would place the sensing elements at an indeterminate distance from the reference plane.

9th Change – Section 4.4.1.2.1 Step 2

From:

 

… Note that a separate E-field and H-field gauge block will be needed if the edge of the probe sensors are at different distances from the tip of the probe.

 

To:

 

… Note that a separate E-field and H-field gauge block will be needed if the center of the probe sensor elements are at different distances from the tip of the probe.




10th Change – Figure 4-6

From:

 

 

To:

 


11th Change – Section 4.4.1.2.2 Step 2

From:

 

… Note that a separate E-field and H-field gauge block will be needed if the edge of the probe sensors are at different distances from the tip of the probe.

 

To:

 

… Note that a separate E-field and H-field gauge block will be needed if the center of the probe sensor elements are at different distances from the tip of the probe.

12th Change – Annex A.2 Bullet 4

From:

 

The measurement plane is parallel to, and 1.0 cm in front of, the reference plane.

To:

 

The measurement plane is parallel to, and 15 mm in front of, the reference plane.

 


13th Change – Annex A.2 Figure A-2

From:

 

Vertical centerline of the acoustic output

(coincident in this case with the vertical centerline of the phone)

 

 

To:

 

{Revert to illustration from 2001 version modified to show 15 mm unless a better illustration is provided to show correct dimensions and preferably in B&W.}


14th Change – Annex A.2.1 Figure A-3

From:

 

 


To:

 

 

 



15th Change – Annex A.2.1 Figure A-4

From:

 

The


To:

 

 

 





 

16th Change – Section 4.3.2.1 Table 4-2

Leave unchanged (deferred to next revision):


Issue F – Introduction of TVC

PINS scope

“Incorporate TVC (test validation coil) tool into the Standard as an illustrative reference (similar to the dipole in the RF) in the T-coil Section 6 and the Annex (for development).  The TVC’s intended use is as a magnetic source for measurement setup validation, to be specified as an open-sourced device.  It is not intended as a substitute for Helmholtz coil calibration of the magnetic sensing probe.””

Rational

ANSI S3.22-2003 specifies a Telephone Magnetic Field Simulator (TMFS).  In this proposal the ANSI S3.22 TMFS is added to the equipment list and the suggestion added to Clause 6 that it be used to validate the test setup before testing.

Proposed Changes

1st Change – Clause 2

Update the reference for ANSI S3.22

 

From:

 

[10] ANSI S3.22-1996, American National Standard, Specification of Hearing Aid Characteristics.

To:

 

[10] ANSI S3.22-2003, American National Standard, Specification of Hearing Aid Characteristics.

 

2nd Change – Clause 3.2

Add to acronyms:

 

TMFS        Telephone Magnetic Field Simulator


3rd Change – Clause 6.1.1.2

Add TMFS to the equipment list:

 

            6. Telephone Magnetic Field Simulator (TMFS)           

 

4th Change – Clause 6.3.1

Add new step 1:


1.   A reference check of the test setup and instrumentation may be performed using a Telephone Magnetic Field Simulator (TMFS).  Position the TMFS into the test setup at the position to be occupied by the WD.  Measure the emissions from the TMFS and confirm that they are within tolerance of the expected values.

5th Change – Add new Clause D.19

Insert new clause D.19:

 

D.19   Telephone Magnetic Field Simulator (TMFS)

A Telephone Magnetic Field Simulator (TMFS) such as one meeting the requirements of ANSI S3.22-2003 may be used to validate the test instrumentation and test setup for Clause 6.  For convenience ANSI S3.22-2003 Figure 6 is reproduced here:

 

 

 



          [1] IEC 60118-1 makes reference to hearing aid output being the same for an acoustic input of 70 dB  SPL and a magnetic input of 100 mA/m. Thus 31.6 mA/m is equivalent to an acoustic input of 60 dB SPL, and an acoustic input of 65 dB SPL  is equivalent to 56.2 mA/m.

          [2] See Section A.3 for location and specification of required measurement points.

          [3] IEC 60118-1 makes reference to hearing aid output being the same for an acoustic input of 70 dB  SPL and a magnetic input of 100 mA/m. Thus 31.6 mA/m is equivalent to an acoustic input of 60 dB SPL, and an acoustic input of 65 dB SPL  is equivalent to 56.2 mA/m.

          [4] The 1025 frequency was selected rather than 1 kHz because a 1 kHz reference frequency may interfere with emission harmonics or test equipment fundamental frequencies.