Doug and Phil, I agree with what you have both said. It is sometimes difficult or impossible to get certain proprietary data or studies published for the general populace. Also, every single point in a spec cannot be experimentally characterized, nor should it be. However, the key requirements in a spec that are main effect variables on the execution, implementation and assessment accuracy of the spec being used should, be and I think are, based on data. It should not be inferred by the technet readership that our industry spec's are determined only by " who screams the loudest " or " who has the fanciest reputation or credentials " at committee meetings. While sometimes these two attributes do affect some of the text of our spec's, I think that the various committee's infact do settle disputes about requirements with experimental findings if no data are available and committee attendee's make reasonable arguments that certain requirements are too extreme or too lax. Now Phil has also hit another point right on the head. I think it is OK for someone to call and ask for supporting data on a particular point. However, if someone thinks a particular requirement is incorrect or should be changed, then THEY NEED TO DO THE PRELIMINARY WORK AT THEIR PLANT TO SHOW WHY AND THEN THEY NEED TO PRESENT IT AT THE NEXT COMMITTEE MEETING. It is so easy to make coments and criticisms about spec requirements but not so easy to show in an objective manner why. If it is such a big problem, then there should be no issue getting travel approved to " right the wrong ". For example, I know we had a disagreement regarding steam age time and temperature requirement for solderability testing during the drafting of ANSI J STD-002. This disagreement was discussed at length and finally an experimental round robin test was devised and both parties agreed, PRIOR TO THE RESULTS BEING KNOWN, to " let the data speak ". Both agreed that if the results came out one way, then the group would adopt one sides position. If the results came out another way, then the other side would prevail. Granted, it took a long time to finish the experiment, but it was finished and the associated IPC reports were printed and are forever saved in the IPC library. The speed with which such round robins are executed is up to the testers and the committee's. Experiments can de devised to be completed within six months if there is a will to do it and issue being settled is a big issue. Best regards, Mark Kwoka Harris Semiconductor ______________________________ Reply Separator _________________________________ Subject: Re: ASSY: Reliability, IPC Specs, IPC Task Groups Author: [log in to unmask] at smtp Date: 2/11/97 10:46 AM Doug, Good explanation of the processes of spec changes. Having been a task group chairman for many years and a member of many committees, I have found that published, non-proprietary, hard data is at best available around year 2050. If the task groups waited to make changes based on the full publioshed data, the IPC specs would still be in the 60's while the suppliers and users were working to much later EU, IEEE, company specs and so forth. The people that call and want a copy of the hard data often have never been to a meeting or have even submitted comments. With a very few exceptions the IPC specifications have withstood the test of time and have become accepted standards that many people can accept and will produce good reliable product. The 5 to 15 people who are the workers on any spec. usually represent a good mix and do not intentionally sand-bag any particular group or company and are most often working to improve the industry standards. Phil Hinton Hinton "PWB Engineering *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * *************************************************************************** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************