Information about PPM since giving up AQL - Historical description of requirements

A

A.C. Mouchet

#1
I am looking for an historical description of the requirements of automotive principals concerning the PPM since the giving up of the AQL. Web sites, books, reviews, ... ASAP. Thank you very much.
 
Elsmar Forum Sponsor

Marc

Hunkered Down for the Duration
Staff member
Admin
#2
I don't know any specific sites, etc., but In my memory AQL started receeding in the late 1980's as the philosophy went from inspection to 'manufacturing responsibility'. I believe the personal computer has in part allowed this as the data necessary before could be overwhelming. In addition, the Cost of Quality started becoming 'interesting' especially as companies started trying to quantify the cost of Bad quality and had some degree of succeess. I first heard ppm in the electronics world. It might have been with respect to 6 sigma. The conversations I remember included simple stuff but most was based on the idea that there is no 'Acceptable Quality Level' (acceptable number of defects) and that serious continuous improvement was necessary. As I remember 6 ppm was a goal at many places. Damn, I've got the 'old timers' disease - can't rmember much any more.

Anyone know the equivalences between AQL and ppm? (Like an AQL of 95% is X ppm.)
 
B

BWoods

#3
I don't know of a way to directly link AQL to PPM. To me that is apples and oranges.

Will this help?

+/- 1sigma = 68.27% = 317,300 ppm outside
+/- 2sigma = 95.45% = 45,500 ppm
+/- 3sigma = 99.73% = 2,700 ppm
+/- 4sigma = 99.9937% = 63 ppm
+/- 5sigma = 99.999943% = 0.57 ppm
+/- 6sigma = 99.9999998% = 0.002 ppm
 
#5
Marc, Didn't Crosby advocate doing away with the AQL with his "Zero Defects" process in the late 60's?
Also the Electronics Industries Association standard for verifying compliance with quality levels in PPM is EIA-555,approved in 1988, Assessment of nonconforming levels in parts per Million (PPM) EIA-554, approved 1988,and my favorite, Guideline on the use and application of Cpk,QB6, 1991.
As for published acceptable quality levels (AQL), those are outlined in the old mil std. Daimler-Chrysler publishes an an acceptable PPM level of 50.
 

Marc

Hunkered Down for the Duration
Staff member
Admin
#6
Sam said:

Marc, Didn't Crosby advocate doing away with the AQL with his "Zero Defects" process in the late 60's?
I think that was the deal.

The problems which come into play are reality and price vs. theories when one starts speaking 'zero defects'.
 
R

rrramirez

#8
Assessment of nonconforming levels in parts per Million (PPM)

:bonk:In the Dr. Wheeler´s book Understanding SPC, paragraph 6.3 there are some explanation related with Cp values and PPM nonconforming. In page 130 he concluded:..."The conversion of capability values into fractions nonconforming is an operation that has no contact with reality. It is nothing more than fantasy, and the results are illusion, if not outright delusions."

IMO this a related matter with the topic in discussion.
 
M

M Greenaway

#9
An AQL is specifically a point on the operating characteristic curve of a sampling plan, and is related totally to probabilities incurred when operating sampling inspection to a specific plan.

PPM on the other hand is a direct measure of non-conformities produced in relation to total production.

There is no strict correlation between the two.
 

Atul Khandekar

Quite Involved in Discussions
#10
Re: Assessment of nonconforming levels in parts per Million (PPM)

rrramirez said:

:bonk:In the Dr. Wheeler´s book Understanding SPC, paragraph 6.3 there are some explanation related with Cp values and PPM nonconforming. In page 130 he concluded:..."The conversion of capability values into fractions nonconforing is an operation thta has no contact with reality. It is nothing more than fantasy, and the results are illusion, if not outright delusions."
IMO this a related matter with the topic in discussion.
The PPM statistic thus calculated represents the 'potential' of that process to produce nonconforming product. This may have some bearing on the downstream processes, if not on what is finally shipped to the customer. However, from the point of view of the operator, PPM may not mean anything, because he wants to know where the process stands 'at this point of time'.
 
Thread starter Similar threads Forum Replies Date
D Preservation of Electronic Data / Information Technology ISO 13485:2016 - Medical Device Quality Management Systems 4
S API Spec.Q1 Standards Version in Purchasing Information Oil and Gas Industry Standards and Regulations 1
eule del ayre Documented Information - Periodic Review of Documents? IATF 16949:2016 / ISO 9001:2015 IATF 16949 - Automotive Quality Systems Standard 34
R Information on obtaining a market authorization for China China Medical Device Regulations 2
B SN95 Respirator Approval Information Other Medical Device Related Standards 0
R Risk assessment on IT containers and the information they contain IEC 27001 - Information Security Management Systems (ISMS) 4
O EN 301 489-1 and EN 301 489-17 - Where do we get the information of the Published versions? CE Marking (Conformité Européene) / CB Scheme 1
K Article 18: Implant Card and information to be communicated. EU Medical Device Regulations 5
K EU MDR Annex 1 Chapter III: Information in the Instructions for Use-23.4 (e) the performance characteristics of the device; EU Medical Device Regulations 1
A GMDN Registration Basic preliminary Information EU Medical Device Regulations 0
J Controlled information versus defined documents / records ISO 13485:2016 - Medical Device Quality Management Systems 3
A Medical device Reporting : Good Faith Effort for Additional information Other US Medical Device Regulations 2
P Cenelec updated standard information CE Marking (Conformité Européene) / CB Scheme 1
Richard Regalado Automotive News TISAX - VDA ISA (information security assessment) VDA Standards - Germany's Automotive Standards 5
JoCam False information provided for Medical Device Registration - What are the implications? Other Medical Device Related Standards 3
adir88 Information of safety can reduce risk now? ISO 14971 - Medical Device Risk Management 12
Richard Regalado What could go wrong with information: Ransomware statistics and facts (2018 to present) IEC 27001 - Information Security Management Systems (ISMS) 0
Q LOT or Serial Number Symbol not used when the information is contained in the UDI? 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 1
A Information about Medical Device Test Laboratories Other Medical Device and Orthopedic Related Topics 4
C Missing routers/documented information Nonconformance and Corrective Action 5
MrTetris Unacceptable risk and information for safety ISO 14971 - Medical Device Risk Management 16
M Is Harmonised EN 1041 (Information Supplied By Manufacturer) Worth Looking At? EU Medical Device Regulations 7
P Predicate Device Information for 510(k) Submission Medical Device and FDA Regulations and Standards News 4
V IS/ISO/IEC 17025:2017 Clause 7, sub clause 7.11 Control of data and information management ISO 17025 related Discussions 1
A Medical Device Contract Manufacturing Requirements and Information - Help wanted ISO 13485:2016 - Medical Device Quality Management Systems 5
H Analog Pressure Gauge with no EN837 accuracy class information General Measurement Device and Calibration Topics 5
M Informational EU – MDCG 2019-12 Designating authority’s final assessment form: Key Information Medical Device and FDA Regulations and Standards News 0
G What information to put on measurement Dimensional Results APQP and PPAP 7
L MDR - Information in the instructions for use - clausole 23.4.(z) EU Medical Device Regulations 2
K AS9100D Clause 7.5.2.a) - What is considered to be "documented information"? AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 5
A Information on good laboratory practices (GLP) for the non-medical or food industry wanted Manufacturing and Related Processes 1
I What kind of information needs to be in a calibration record? General Measurement Device and Calibration Topics 25
M Informational TGA – Medical device patient information leaflets and implant cards Medical Device and FDA Regulations and Standards News 0
Q AS9120 7.5.3.2 Control of Documented Information - Audit Nonconformance AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 20
G Posting Measuring Equipment Accuracy for User Information General Measurement Device and Calibration Topics 4
J EC REP information and CE Mark - Component of a system that is not a medical device EU Medical Device Regulations 2
M Informational EU – Medical devices: Implementation of Regulation (EU) 2017/745 on medical devices (MDR) – Information from the Irish and German delegations Medical Device and FDA Regulations and Standards News 0
D ISO 9001:2015 Clause 8.4.3 "Information for External Providers" buying from online retailers. ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 10
B Practical ideas for information labelling in healthcare environment IEC 27001 - Information Security Management Systems (ISMS) 2
M Informational US FDA – Historical Information about Device Emergency Use Authorizations Medical Device and FDA Regulations and Standards News 0
M Informational US FDA – Patient Preference Information (PPI) in Medical Device Decision-Making Medical Device and FDA Regulations and Standards News 0
M Informational USFDA final guidance – Recommended Content and Format of Non-Clinical Bench Performance Testing Information in Premarket Submissions Medical Device and FDA Regulations and Standards News 0
R Where to get information - M6 per WA900 Manufacturing and Related Processes 1
M Informational FDA Posts Information about Ethylene Oxide Sterilization and Medical Devices Medical Device and FDA Regulations and Standards News 0
L VDA 1 Documented Information and Retention (new revision 4, August 2018) VDA Standards - Germany's Automotive Standards 0
R Publication of user information in manufacturer website for medical devices Other Medical Device Regulations World-Wide 2
E EU MDR GSPR 23.1 information on website CE Marking (Conformité Européene) / CB Scheme 2
M How To Define ISMS (information Security Management System) Scope IEC 27001 - Information Security Management Systems (ISMS) 9
M Authorised Representative Contact Information EU Medical Device Regulations 3
Q Information for safety EN ISO 14971:2012 - Customer Risk Reduction ISO 14971 - Medical Device Risk Management 6

Similar threads

Top Bottom