Mike, Ken Although I have not read much of it, I'd recommend a book by Ed Schilling on Statistical Acceptance Sampling, the exact title of which I forget. It was very comprehensive and included a description of one he developed himself which has two features I like: it allows acceptance only on zero nonconformances and is defined by a Lot Tolerance Percent Defective (LTPD). LTPD (not a good choice of terminology) is the largest fraction nonconforming that has a 0.1 or 0.05 (depending on the plan) probability of acceptance. For example, if you decide you cannot tolerate more than 8% nonconforming material in a lot, you might say that you want a sampling plan that will have a probability of 0.1 of accepting a lot with that % nonconforming. Following Schilling's recipe, you would calculate the number of units to inspect (it depends on the lot size) and accept the lot if you found no nonconformances in the sample. The advantages to such an approach are: sample size is relatively low by working from an LTPD rather than an AQL (as in Z1.4), the plan is oriented to protect the consumer rather than the producer by accepting on zero nonconformances, you have at least not demonstrated that there is one in the lot (Z1.4 allows acceptance, in some cases, with 1 or more nonconformances in the sample). IPC has had a very simple table appearing in a number of documents over the past two years that defines zero acceptance number sampling plans, although based on an AQL. It is on page 20 of 6012A, for example. It has the two virtues of a zero acceptance number and of being very easy to use. If you are working with variable (something measured) rather than attribute (pass or fail) data, ANSI/ASQC Z1.9 is worth knowing about. (It is comparable to MIL-STD-414.) If quantitative measurements are available and hard to make, this standard may be useful. Beyond these, you could look into Skip Lot Sampling plans to use, which would help you reduce inspection once a supplier's performance had been established as acceptable. ANSI/ASQC S1-1987 (or a later version, if one exists) specifies such plans. ASQ has a slender book by Kenneth Stephens called "How to Perform Skip-Lot and Chain Sampling", ISBN 0-87389-325-5. If your product is coming off the line in a continuous stream, rather than in lots, you may want to look into "How to Perform Continuous Sampling", also by Stephens, ISBN 0-87389-330-1 from ASQ. MIL-STD-1235 specifies a variety of plans. I don't know if there is an ASQ equivalent. Hope this helps some. Lou -----Original Message----- From: Keel, Mike [SMTP:[log in to unmask]] Sent: Wednesday, March 07, 2001 4:02 PM To: 'TechNet E-Mail Forum.'; 'Lou Hart' Subject: RE: [TN] MIL- 105D or MIL-105E? What is new one? Lou, we all benefit if you share -----Original Message----- From: Lou Hart [mailto:[log in to unmask]] Sent: Wednesday, March 07, 2001 7:06 PM To: [log in to unmask] Subject: Re: [TN] MIL- 105D or MIL-105E? What is new one? Ken, 105 was cancelled 5 or 6 years ago. Use Ansi/ASQC Z1.4-1993, Sampling Procedures And Tables for Inspection by Attirbutes. I don't know that it has been revised since 1993. You can get this from the American Society for Quality. Personally, I am not very fond of this standard. Other sampling methods are better, in my opinion. If you or other TechNetters want to know more, please say so. Lou Hart -----Original Message----- From: Ken Patel [SMTP:[log in to unmask]] Sent: Wednesday, March 07, 2001 1:12 PM To: [log in to unmask] Subject: [TN] MIL- 105D or MIL-105E? What is new one? Quality Guru, Can anyone give me an update on sampling plan MIL- 105D or MIL-105E? I heard that it was replaced by new standard? What is the name of that document? re, ken patel ------------------------------------------------------------------------ --------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ------------------------------------------------------------------------ --------- ------------------------------------------------------------------------ ---- ----- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ------------------------------------------------------------------------ ---- ----- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------