Measurement Systems Analysis
Measurement systems analysis is an important topic in statistics and quality for engineering, manufacturing, laboratory practice and business process applications. A new ASTM International standard, E2782, Guide for Measurement Systems Analysis (MSA), covers many core issues of MSA.
E2782 was developed by Subcommittee E11.20 on Test Method Evaluation and Quality Control, under the jurisdiction of ASTM International Committee E11 on Quality and Statistics.
According to Stephen Luko, a statistician with Hamilton Sundstrand, and a longtime member and former chairman of E11, when an object is measured and a result presented, typically some decision will be made and/or action taken because of the measurement result. In such cases, Luko notes, it is always reasonable to ask the following questions:
“From a practical point of view, the user of a measured quantity wants to know how different might the measured quantity be from the true value of what has been measured,” says Luko. “This is the essence of MSA.”
As an example, Luko says that if the measurement error is too large, this result may render the measurement results either useless or of limited value.
“There are several components to measurement error as well, and the statistical practice of measurement systems analysis shows you how to separate these components and how to improve measurement performance for the various components,” says Luko.
The new standard will be useful anywhere measurement systems are used and/or where measurement error is important to assess. This includes work by many ASTM committees, along with user communities found in manufacturing and engineering firms, and in more general business practices.
As currently approved, E2782 applies to variable measurements and nondestructive applications. E11.20 plans to incorporate destructive measurement applications as well as applications involving attribute type measurements in future revisions of the standard and invites all interested parties to contribute to this work.
Technical Information: Stephen Luko, Hamilton Sundstrand, Windsor Locks, Conn.
ASTM Staff: Christine Basile