Posts Tagged ‘ASQC-Z1.4’

Whatever happened to MIL-STD-105?

Tuesday, May 24th, 2011

MIL-STD-105, “Sampling Procedures and Tables for Inspection by Attributes,” is another of those popular military standards that got cancelled during Mil Spec reform in the mid-1990′s.  The documents referenced in the cancellation notice can cause confusion for users, so some assistance with this can be helpful.

The last revision of the MIL-STD-105 was Revision E from 1989.  This last issue was cancelled three times, first in 1995, then in 2001 and finally in 2008.  Cancellation Notice 1 from 1995 simply replaced the standard with ASQC-Z1.4 (now ASQ-Z1.4).  This ASQ document is actually a reprint of the MIL-STD-105 and an obvious choice to use in lieu of the MIL Standard.

However, Notice 2 from 2001 really put a wrench in the works.  It stated “MIL-STD-105E … is hereby canceled without replacement.  Current DOD PREFERRED METHODS FOR ACCEPTANCE OF PRODUCTS are described in MIL-STD-1916… and should be considered for future acquisitions.”  However, MIL-STD-1916 is an administrative standard.

In fact, MIL-STD-1916 was developed to encourage defense contractors to submit process control (prevention) procedures instead of using prescribed sampling requirements like those detailed in ASQ-Z1.4.  In other words, the standard supports the DoD desire to change contractual requirements from a system of acceptable quality levels to one of continuous improvement.

Quality documents referenced by MIL-STD-1916 include ASQ-B1, B2, and B3, ISO-8402, and ISO-9000 (ASQ-Q9000) and ISO-9004 (ASQ-Q9004).  They are all quality standards, but do not address the issue of sampling by attributes, with the many tables that ASQ-Z1.4 contains.

Apparently, this approach got some push-back because in 2008, Cancellation Notice 3 again modified the replacement information.  It now allows for use of either the MIL-STD-1916 or the ASQ-Z1.4.

And while we’re on the topic of the ASQ-Z1.4, we should also mention the ASQ-Z1.9 standard, “Sampling Procedures and Tables for Inspection by Variables for Percent Non-conforming.”  It’s the replacement document for the cancelled MIL-STD-414 (with the same title).  The two ASQ documents are often purchased at the same time and can really be considered to be a set.

All the standards above can be purchased from Document Center Inc.  You can use our website, www.document-center.com, but if you need any of the obsolete documents, you’ll get a quote before you purchase.  That’s because we want to confirm that you understand you’re purchasing a withdrawn document prior to purchase.  Or you may prefer to contact us by phone (650-591-7600), fax (650-591-7617) or email (info@document-center.com).  We’re able to provide you with many obsolete standards, as well as help you determine what replacement documents are available.

All time best selling Standards on Sampling and Statistical Process Control

Friday, October 8th, 2010

It’s said if you can measure it, you can manage it, and Statistical Process Control is the tool to use!  So it’s no surprise that there are a wide range of standards on the subject.  Here’s our list of the top 10 Standards on Sampling and Statistical Process control.

ASQ-Z1.4, Sampling Procedures and Tables for Inspection by Attributes

ASQ-Z1.9, Sampling Procedures and Tables for Inspection by Variables for Percent Nonconforming

These 2 Standards replace MIL-STD-105 and MIL-STD-414both of which are now obsolete. Filled with pages of tables for use with a continuous supply, the documents are our current best-selling sampling standards.  The Z1.4 covers go/no go data, the Z1.9 covers measurement.

Zero Acceptance Number Sampling Plans is often used as an alternative to the MIL-STD-105/ASQ-Z1.4 Inspection systems.  It is based on C=0 concept developed by author Nicholas Squeglia back in 1961.  The 5th edition is the current revision of this item.

During the last few years, the ISO standards on this topic have seen greater usage as well.  Top sellers include the ISO-2859 series, the ISO-11462 series, the ISO-3534 series, and the ISO-5725 series.

ISO-2859-10, Sampling procedures for inspection by attributes – Part 10: Introduction to the ISO 2859 series of standards for sampling for inspection by attributes, is a good starting point for the ISO-2859 set.  It provides a general introduction to acceptance sampling by attributes and provides a brief summary of the attribute sampling schemes and plans used in Parts 1 through 5. The standard also provides guidance on the selection of the appropriate inspection system for use in a particular situation.

ISO-11462-1, Guidelines for implementation of statistical process control (SPC) – Part 1: Elements of SPC, and ISO-11462-2, Guidelines for implementation of statistical process control (SPC) – Part 2: Catalog of Tools and Techniques, are two additional useful standards.  They provide concepts, tools and techniques to help an organization in planning, implementation and evaluation of an effective statistical process control (SPC) system.

ISO-5725-1, Accuracy (trueness and precision) of measurement methods and results – Part 1: General principles and definitions, is an introduction to the ISO-5725 series.  It outlines the general principles to be understood when assessing accuracy of measurement methods and results.  It can also be used to establish practical estimations of the various measures by experiment.  The standard may be applied to a very wide range of materials, including liquids, powders and solid objects, manufactured or naturally occurring.

For Statistics – Vocabulary and symbols, the ISO-3534 series covers all the bases:

ISO-3534-1, Part 1: General statistical terms and terms used in probability

ISO-3534-2, Part 2: Applied statistics

ISO-3534-3, Part 3: Design of experiments

ASTM International (formerly the American Society for Testing and Materials) also has a number of standards on the topic of Sampling and Statistical Process Control.  We often sell the following:

ASTM-E122, Standard Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot or Process.  This standard is intended for use in determining the sample size required to estimate, with specified precision, a measure of quality of a lot or process. The practice applies when quality is expressed as either the lot average for a given property, or as the lot fraction not conforming to prescribed standards.

Should you have any questions about the above standards, or need more suggestions to get the information you need, please contact us at www.document-center.com, info@document-center.com, or phone us at 650-591-7600.  We’re always ready to help you out.