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JT-32 Electron Tube Safety Committee

Thursday, May 18, 2000
Hyatt Hotel
Long Beach, CA

1 Committee organization and procedures

1.1 Membership and attendance
Self-introductions were made, attendance taken, and it was determined that a quorum was present.

1.2 Approval of the Agenda
The Committee unanimously accepted the Agenda as presented.

1.3 Approval of the Minutes
The Committee unanimously accepted the Minutes of the last meeting as corrected. Note that Mr. Chenoweth is the voting member of the P-32 Committee for Thomson.

ACTION ITEM - Send out the revised Minutes to the membership.

1.4 Correspondence
- No correspondence was received.
- EDSC will meet in Corning.
- UL is reorganizing the committees and panel groups

1.5 Review of the Committee's scope
No review was needed.

1.6 Report on the EDSC
No report was given.

2 Old business

2.1 International safety standards

2.1.1 IEC61965, Impact testing standard
13-14 Sept. is the date of the next TC39 meeting in Corning.

2.1.2 Laminated film on CRT faceplate
Studies are continuing.

2.1.3 IEC/TC39/WG2, X-radiation standard task force report
- Mr. Chenoweth stated that the intent is to adopt the EIAJ method for limit curves in the EIA-197 revision.
- Mr. Chenoweth discussed the use of EXCOM software for improving the determination of X-radiation parameters.

ACTION ITEM - Mr. Chenoweth will send attached text on his presentation on the task force report.

2.1.4 The influence of differences in cabinets on testing X-radiation
- Mr. Chenoweth led off discussion on the influence of differences in cabinet shape and dimensions on X-ray testing. The present standard uses a cabinet shape that is not generally used today. As a consequence, he recommended that the distance used for X-ray measurement. He demonstrated high-voltage vs Ib plots that are used to determine safety parameters. The goal is to determine correct reproducible distances for measuring X-rays. He reported that the Victoreen detector, MAB604, provides reproducible results. He urged the Committee to review their current practices for future discussion on possible modification to the existing standard.
- Mr. Rowe recommended that the EIA R1 should be asked for their opinion on this issue.

ACTION ITEM - Mr. Chenoweth will send attached text on his presentation on cabinet effect on X-ray measurements.

2.1.5 Implosion testing of new CRT families
- Mr. Swank described concerns about testing tubes with 4 x5, 3x4, and 16x9 aspect ratios. 4x5 and 16x9 flat picture tubes are very sensitive to sudden breakage during testing; i.e., the plateau for catastrophic failure is very short especially for tubes where the end of the guard band is very close to the inner face curve that results in high compression force. High energy testing results in failure. IEC is currently approved a 14 J missile for testing of flat tubes; UL and CSA are equally concerned. Mr. Swank felt that the various companies review their efforts of testing on implosion testing of new CRT families

2.2 Standards and document review

2.2.1
- EIA-500-A, Recommended practice for the measurement of X-radiation from projection cathode-ray tubes
The Committee reviewed the document, discussed issues, and proposed, seconded and unanimously approved reaffirmation.
- EIA-501-A, Recommended practice for the measurement of X-radiation from raster-scanned direct-view television picture tubes
The Committee reviewed the document, discussed issues, and proposed, seconded and unanimously approved reaffirmation.
- EIA-502-A, Recommended practice for the measurement of X-radiation from non-raster-scanned direct-view television picture tubes
The Committee reviewed the document, discussed issues, and proposed, seconded and unanimously approved reaffirmation.
- EIA-503-A, Recommended practice for the measurement of X-radiation from direct-view television picture tubes
The Committee reviewed the document, discussed issues, and proposed, seconded and unanimously approved reaffirmation.

2.3 Environmental issues
No pertinent issues were offered.

3 New business
No new business was offered.

4 Selection of next meetings
Monday-Tuesday, 12-13 Sept. 2000 was preferred by the Committee for the next meeting in Corning using the present schedule as Long Beach, California.

5 Adjournment
The Committee moved, seconded, and unanimously agreed to adjourn at 11:20 AM.

6 Actions items
· Mr. Chenoweth will send attached text on his presentation on the task force report.
· Mr. Chenoweth will send attached text on his presentation on cabinet effect on X-ray measurements.
· Send out the revised Minutes to the membership.
· Reaffirm documents EIA-500-A, 501-A, 502-A, and 503-A.

This meeting was conducted in accordance with the EIA legal guidelines and the manual of organization and procedures.

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