Transition from ASCLD/LAB Legacy
to ISO/IEC 17025
1.0
Objective
To set
forth selected and important ISO requirements that
exceed ASCLD/LAB Legacy program requirements which are
new and of interest to the Firearms-Toolmarks community.
2.0
Identified
Requirements and Applications
2.1 The
laboratory shall evaluate the suppliers of critical
consumables, supplies and services, and maintain records
of these evaluations and list those approved. [4.6.4]
2.1.1 This
may include calibration and maintenance services for
balances, microscopes and consumables, which may include
gunshot residue supplies.
2.2 The
laboratory must estimate the uncertainty involved with
all measurements critical to the examination outcome.
[5.4.6]
2.2.1 Only
uncertainty of measurement in quantitative testing is
considered.
2.2.1.1 Examples
of such measurements could include those which place or
border the measurement within a legal or regulatory
standard. This may include linear measurements
associated with barrel and overall lengths of firearms,
projectile velocity measurements and bullet weights for
energy calculations.
2.2.1.2 Examples of
instruments which may affect uncertainty calculations
and may need to be calibrated could include calipers,
micrometers, rulers, microscopic reticles, chronographs
and balances.
2.2.2 All
components which may influence uncertainty of
measurements should be considered and documented
(manufacturer error rate is one such consideration).
2.2.3 If
the reproducibility experiment is designed in such a way
that variability due to all of the major sources of
uncertainty is sampled, then reliable estimates of
uncertainty can be based entirely on experiment without
having to resort to the mathematics and theory found in
the ISO Guide to the Expression of Uncertainty in
Measurement.
2.2.4 The
statistical spread results in a series of measurements
may yield, through its standard deviation, a measure of
the uncertainty. This could be achieved by having all
examiners within their unit take test measurements,
collecting the aggregate data, and then having standard
deviations calculated (this procedure will incorporate
instrumentation errors). A plus or minus figure could be
assigned to a measurement based on one or two standard
deviations from the mean.
2.3
Reference
collections that are maintained for identification,
comparison or interpretation purposes should have their
specimens uniquely identified, fully documented and
properly controlled. [5.6.3.2]
2.3.1
Examples may
include firearms, ammunition and fired-specimen
collections.
2.3.2
Attempts
should be made to appropriately classify and
characterize firearm reference collections and their
associated components.
2.3.3
Components of ammunition reference collections may be
traceable by the lot number on the ammunition boxes, the
head stamp, or the purchase practices.
2.4
When
opinions and interpretations are included, the
laboratory shall document the basis upon which the
opinions and interpretations have been made. Opinions
and interpretations shall be clearly marked as such in
the test report. [5.10.5]
2.4.1 Reports
which contain test results enhanced with the conclusion,
opinion or interpretation shall in some way notify the
customer that the report contains conclusions, opinions
and interpretations of the person issuing the report.
This may be accomplished in a variety of ways.
2.4.1.1
A heading
for the results section of the report that reads
“Results and Conclusions,” or “Results and
Interpretations,” or “Results and Opinions.”
2.4.1.2
A footer or
preformatted message on the report, such as:
“This
report contains the conclusions, opinions and
interpretations of the analyst whose signature appears
on the report.”
2.4.1.3
Or, if a
heading or preformatted message is not used, the author
of the report may use appropriate wording directly in
the text of the report.
“It is
the opinion of this examiner that…”
References:
General Requirements for the Competence of Testing and
Calibration Laboratories, International Standard, ISO/IEC
17025, Second Edition 2205-05-15, Reference number ISO/IEC
17025:2005(E)
ISO/IEC
17025:2005 / 5.10.5 Opinions and interpretations, ASCLD/LAB
Discussion, Interpretation and Application; Adopted by
the ASCLD/LAB Board of Directors on September 14,
2008-10-22
2006
Supplemental Requirements for the Accreditation of
Forensic Science Testing Laboratories, Corresponds to
ISO/IEC 17025:2005; Effective Date: January 24, 2006;
Approved by: ASCLD/LAB Board of Directors
Guidelines for the Accreditation of Forensic Testing
Laboratories; CAN-P-1578; September 2003
A2LA
Guide for the Estimation of Measurement Uncertainty in
Testing; July 2002; Edited by Thomas M. Adams
Final
04/06/09
