|Committee E01 Preparing to Implement Performance-Based Methods
At its May 2004 meeting, the executive subcommittee of E01 on Chemical Analysis of Metals, Ores, and Related Materials unanimously committed to develop and implement performance-based test methods for the quantitative analysis of materials under its jurisdiction. Performance-based test methods define general approaches for sampling, sample preparation, and making measurements on a specified type of material. They set maximum allowable uncertainties for each component of uncertainty of each measured constituent over its validated concentration range. The key criteria of compliance with a performance-based standard test method is the quality of data generated (uncertainty) rather than adherence to procedure.
The new E01 performance-based approach is based on ASTM standards E 691, Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method; E 1601, Practice for Conducting an Interlaboratory Study to Evaluate the Performance of an Analytical Method; E 2165, Practice for Establishing an Uncertainty Budget for the Chemical Analysis of Metals, Ores, and Related Materials, and a proposed new standard, Practice for Designing and Validating Performance Based Test Methods for the Analysis of Metals, Ores, and Related Materials, which is now on ballot. A second proposed Practice for Implementing Standard Performance Based Test Methods for the Analysis of Metals, Ores, and Related Materials will be balloted shortly and describes how laboratories will be expected to comply with performance-based standards in a way that is compliant with ISO 17025, General Requirements for the Competence of Testing and Calibration Laboratories.
E01 committee member Dean Flinchbaugh, who presented a workshop on performance-based test methods during the May meeting, says that Committee E01, ASTM as a whole, the laboratories that use its test methods, and the bodies that accredit laboratories will benefit from the use of performance-based methods. Some of these benefits include: (1) having standard test methods that are more resistant to obsolescence, (2) streamlining test method validation and interlaboratory testing, (3) having more consistent data quality reported from multiple laboratories that use the same test method, (4) expanding procedure flexibility in user laboratories, (5) having more consistent measurement uncertainty information to facilitate product conformity decisions, and (6) simplifying internal and external audits by having fewer procedural details to examine.
Further, Flinchbaugh says the new approach is compatible with existing documents that are used internationally. Examples include compliance with ISO 17025, and ASTM Practices E 1601 and E 2165, as well as compatibility with existing test methods and proficiency test programs. The performance-based concepts are also applicable to other ASTM technical committees that write analytical chemistry-based test methods.
For further technical information, contact Dean Flinchbaugh, Flinchbaugh Consulting Co., Bethlehem, Pa. (phone: 610/868-3530). Commitee E01 meets Nov. 8-10 at NIST in Gaithersburg, Md. For membership or meeting details, contact Tom OToole, ASTM International (phone: 610/832-9739). //
Copyright 2004, ASTM International