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At the 1997 annual meeting of ISO/TC 69/SC 6, Working
Group 7 was formed and charged to report on the relationship between
ISO 5725 Accuracy (precision and trueness) of Measurement Methods
and Results and the ISO Guide to the Expression of Uncertainty
in Measurement (GUM). The result of that work encouraged SC 6
to start two technical reports on statistical analysis to support
the GUM.
Last full meeting of ISO/TC69/SC6/WG7:
Thursday, June 10, 1999
Polish Institute for Normalization
Warsaw, Poland
Members in attendance:
Ms. Carroll Croarkin, USA, Convenor WG 7
Dr. Steve Ellison, UK, Project leader WG 7
Dr. Michele Boulanger, USA
Mr. Rudolph Kittlitz, USA
Dr. Erik Holst, Denmark
Dr. Ojima, Japan, Chairman ISO/TC69/SC6
Prof. Takasaki Miyazu, Japan
Mr. Christophe Perruchet, France, Chairman ISO/TC69
Dr. Paul Tyrregod, Denmark
Ms. Yoriko Yasuda, Japan
Summary of meeting:
Carroll Croarkin presented an outline and first draft
for a technical report, Statistical Methods of Uncertainty Analysis for Metrology and Scientific Laboratories.
The working group approved of the general approach and offered
comments to be incorporated into the draft. It also decided to
expand the scope to include analyses appropriate for chemical
measurements. Göran Nilsson, Sweden, volunteered to prepare
this section. The group also decided to expand the scope to include
uncertainties associated with calibrations and instructed the
project leader to prepare a new draft by the end of the summer
in preparation for bringing the document to the CD stage at the
reunion of TC69 in June, 2000.
Steve Ellison presented an outline and first draft
for a technical report, Statistical Methods of Uncertainty
Analysis for Test Laboratories. The working group approved
of the general approach and asked Dr. Ellison to complete the
draft and add examples. WG 7 also instructed the project leader
to prepare a new draft by the end of the summer in preparation
for bringing the document to the CD stage at the reunion of TC69
in June, 2000.
Documents in Progress:
Draft 1. Statistical Methods of Uncertainty Analysis for Metrology and Scientific Laboratories
Project leader: Carroll Croarkin (carroll.croarkin@NIST.gov),
US
Countries participating: UK, France, Denmark, Japan, US
Scope: This document is intended for metrological and scientific
applications where resources are available to assess sources of
uncertainty in measurement process. The document will provide
guidance on data collection and statistical analyses for assessing
the effects of random and systematic errors on the measurement
process and rules for computation of the uncertainty of a reported
result that are consistent with the GUM. It will rely heavily
on ISO 5725, particularly parts 2 & 3, in working through
an example with data from a 3-level nested design. The first draft
of the document can be accessed from the link below.
Send comments by email to carroll.croarkin@NIST.gov.
Comments will be posted on this web page as they are received.
2. Measurement Uncertainty in Test Laboratories
from Results of Interlaboratory Studies
Project leader: Steve Ellison (slre@LGC.CO.UK),
UK
Countries participating: UK, France, Denmark, Japan, US
Scope: This report is intended for test laboratories that do not
have the resources to fully assess all sources of uncertainty
in their measurement processes or to develop mathematical models
that relate input variables to outputs. The document will demonstrate
how to use estimates of repeatability, reproducibility and trueness
from interlaboratory studies, following the procedures of ISO
5725, to calculate uncertainties of test results consistent with
the GUM.
At this time, the draft document is available only in paper copy.
Contact the author by email at slre@LGC.CO.UK.
Next meeting of WG 7:
The next full meeting of WG7 will take place concurrently with the reunion of ISO/TC 69/SC6 and will take place at:
Tentative Agenda
Tuesday, May 23, PM Session
Chair: Carroll Croarkin, US
Wednesday, May 24, 9:00-13:00
Chair: Carroll Croarkin, US
Wednesday, May 24, 14:00-17:00
Chair: Christophe Perruchet, France
Thursday, May 25, 9:00-13:00
Chair: Steve Ellison, UK
Friday, May 26, 9:00-13:00
Chair: Steve Ellison, UK
Those interested in attending a WG 7 meeting should contact
Mail: Ms. Carroll Croarkin, Rm 353 Bldg. 820, NIST,
Gaithersburg, MD, 20899
Working Group Membership and Address List
Information on the Statistical Engineering Division of the National
Institute of Standards and Technology can be found at http://www.itl.nist.gov/div898/
.
Information on the US Technical Advisory Group to ISO TC 69 can
be found at
http://standardsgroup.asq.org/about/s/sstands.htm
.