Analysts in laboratories that use regression-based methods to determine uncertainty in data and customers that request such measurements will be the primary users of a new standard recently approved by ASTM International Committee
D19 on Water. ASTM
D7366, Practice for Estimation of Measurement Uncertainty for Data from Regression-Based Methods was developed by Subcommittee
D19.02 on Quality Systems, Specification and Statistics.
According to Lynn Vanatta, chair of the measurement uncertainty task group within D19.02, and manager of ion-chromatography research and statistics at Air Liquide-Balazs, D7366 fills a gap in the metrology standards arena. "While measurement uncertainty is becoming more and more of a concern and while there are documents that address the calculation of this quantity, the focus has been on measurements that do not involve regression," says Vanatta. The more involved statistical approach of regression is needed when instrumental responses such as peak area or absorbency have to be transformed into useful units such as concentration. "ASTM
D7366 provides a statistically sound method to calculate the overall uncertainty in data from such analytical methods," says Vanatta.
All interested parties are invited to join in the standards developing activities of Subcommittee
D19.02.
ASTM International standards can be purchased from Customer Service (phone: 610-832-9585;
service@astm.org) or at
www.astm.org.
For technical Information, contact Lynn Vanatta, Air Liquide-Balazs (phone: 972-995-7541;
lynn.vanatta@airliquide.com). Committee
D19 meets Jan. 25-29, 2009, in Cocoa Beach, Fla. For ASTM meeting or membership information, contact Brynn Murphy, ASTM International (phone: 610-832-9640;
bmurphy@astm.org).
Release #8088/Nov08