ISO Guide 25, ISO 17025 and Optical
Metrology: An Assessor’s Perspective
Gene A. Zerlaut
SC-International Inc.
CORM 2000
Rochester, NY
May 19, 2000
ISO/IEC 17025 - General Requirements for
the Competence of Testing and Calibration
Laboratories
• Approved by ISO & IEC Member Nations in 1999
• First edition published on December 15, 1999
• Laboratories will be permitted by A2LA to be
accredited to both 17025 and Guide 25 in the
second half of 2000
• Mandatory accreditation to ISO/IEC 17025 will be
phased in by A2LA over the next two years
Broad Comparison of Guide 25 and 17025
ISO/IEC 17025
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•
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Scope
Normative References
Terms and definitions
Management requirements
– Fourteen criteria
elements
• Technical requirements
– Nine criteria elements
• Annexes (informative)
• Bibliography
ISO/IEC Guide 25
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•
•
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Scope
References
Definitions
Requirements
– Thirteen criteria
elements
ISO-IEC 17025 Management Requirements
• Organization and
management
• Quality system
• Document control
• Review of . . . Contracts
• Sub-contracting tests/cal
• Purchasing services &
supplies
• Service to the client
• Complaints
• Control of nonconforming testing or calibration
• Corrective action
• Preventive action
• Control of records
• Internal audits
• Management reviews
ISO/IEC 17025 Sections With Essentially No Differences from Guide 25
• Management requirements
– 4.5 Sub-contracting
– 4.8 Complaints
– 4.13 Internal audits
• Technical requirements
– No new ideas, but more detail
– Details covered in subsequent overheads
ISO/IEC 17025
Differences: 4.1 Organization
• 4.1.1 - Laboratory shall be an entity that can
be held legally responsible - versus legally
identifiable (a subtle difference)
• 4.1.2 - Laboratory responsible for satisfying
the client, regulatory authorities and
organizations providing recognition
• 4.1.4 - Potential conflicts of interest must be
identified
ISO/IEC 17025
Differences: 4.2 Quality System
• Detailed requirements for quality policy
statement
• Less prescriptive of what must be in Quality
Manual, except that
– Quality Policy Statement
– Structure of all documentation used in quality
system
– Roles and responsibilities of technical management
and quality manager
must be in the Quality Manual
Additional Calibration Program
Requirements for 4.2 Quality System
• Z540-1/A2LA Requirements (Quality Manual)
– Policy establishing/changing calibration intervals*
– Policy on techniques used to determine
measurement uncertainty
• A2LA Requirements per ANSI/ASQC M1-1987
– Assure accuracy by use of TUR  4:1 by controlling
equipment, procedures, and calibration intervals, or
– Use of statistical control to obtain measurement
assurance using check standards, control charts,
round robins and measurement audits.
*e.g., per Annex A of ISO 10012-1
ISO/IEC 17025
Differences: 4.3 Document Control
• Incorporates ISO 9001 clause 4.5 requirements
• Contains specific requirements for control,
review and approval, issue and amendment of
documents
17025 also includes Guide 25’s clause 5.2.(d)
relating to procedures for control and
maintenance of documentation
ISO/IEC 17025 Differences: 4.4 Requests,
Tenders, Contracts
• NEW
– Identification of customer needs
– Ensure capability to meet needs
– Handle changes and deviations
– Incorporates ISO 9001 requirements
• From Guide 25, clause 5.2(i)
– Arrangements for reviewing new work
ISO/IEC 17025 Differences: 4.6 Purchasing
• New Requirements (taken from ISO 9001)
– Inspection/verification to ensure purchased items
meet specifications
– Requires records of such inspections/verifications
– Review of purchasing documents prior to release
– Evaluation of suppliers of consumables, supplies
and services (including outside calibration services)
• Also combines some Guide 25 requirements
from clause 10.8 and section 15.0
ISO/IEC 17025
Differences: 4.7 Service to Clients
Major new requirement:
• Cooperation with clients
• Notes cover various aspects of laboratory-client
relationships
• Equivalent to ISO 9001 clause 4.19 on
Servicing
ISO/IEC 17025
Differences: 4.9 Non-conforming Work
• More prescriptive procedures for dealing with
non-conformities in testing, results, reporting
• Requires formal corrective action procedures
under most circumstances
• A2LA Calibration Program requirements
additionally mandate that calibration reports
contain a statement of any corrective actions
bearing on the calibrations
ISO/IEC 17025
Differences: 4.10 Corrective Action
• Now prescriptive, and requires:
–
–
–
–
Root cause analysis
Selection and implementation of corrective actions
Monitoring of corrective actions
Follow-up partial audits
• Essentially expands the brief mentions of
corrective action in Guide 25
ISO/IEC 17025
Differences: 4.11 Preventive Action
• Wholly new requirement mandates:
– Identification of opportunities for improvement and
potential sources of non-conformities
– Action plans
– Preventive action (PA) procedures shall include
initiation of PA and application of controls to ensure
effectiveness
• No equivalent in Guide 25
ISO/IEC 17025
Differences: 4.12 Records
• New Aspects:
– Requires prescriptive procedures for identification,
collection, indexing, access, filing, storage,
maintenance and disposal, regardless of media form.
– Covers quality system and technical records
• Other requirements consistent with Guide 25
• A2LA’s Calibration Program also requires:
– Retention for not less than 5 years
– Inclusion of “as found” results
ISO/IEC 17025
Differences: 4.14 Management Reviews
• Now more prescriptive; reviews must include:
–
–
–
–
–
–
suitability of policies & procedures
reports from managerial and supervisory personnel
results of both internal and external audits
corrective and preventive actions
results of interlaboratory and/or proficiency tests
client feedback and complaints
• No longer need be annual, but must be
periodic; annual reviews are suggested
ISO/IEC 17025 Technical Requirements
• General
• Personnel
• Accommodation & Environmental Conditions
• Test/Calibration
methods and method
validation
• Equipment
• Measurement
traceability
• Sampling
• Handling of test and
calibration items
• Assuring quality of test
and calibration results
• Reporting the results
ISO/IEC 17025
Differences in Technical Requirements
More prescriptive than Guide 25, but no
new ideas.
The most significant details are described in the
following slides
The following slides also delineate A2LA &
NVLAP Calibration Program requirements
ISO/IEC 17025 Differences: 5.2 Personnel
• Much more prescriptive than Guide 25
– supervision of trainees
– appropriate education, training & experience for
specific tests
– policy and procedures for training
– suggests minimum content of job descriptions
• ANSI/NCSL Z540-1 requires that the training
of test personnel be maintained up-to-date
• A2LA requires individual approval of staff
performing calibrations in the field
ISO/IEC 17025 Differences:
5.3 Accommodation & Environment
• Little change from Guide 25
• A2LA’s Calibration Program requirements
include additional details, several of which are:
– maintain records of continuous temperature &
relative humidity for five years, or more
– control must be exercised commensurate with the
uncertainties claimed; affect on uncertainties must
be demonstrated
– other factors such as air cleanliness, vibration,
electrical power and EMI may require control
ISO/IEC 17025 Differences:
5.4 Test & Calibration Methods
• Significantly more detailed than Guide 25
• Laboratory-developed and non-standard
methods must be validated
• Format of such in-house methods is suggested
• Validation requirements are given, and
validation techniques suggested
• Determination of uncertainty of measurement
now required of both testing and calibration
laboratories
ISO/IEC 17025 Differences: Resources
for Determining Uncertainties
• References to the measurement of uncertainty*
– ISO/TAG 4/WG3 “Guide to the Expression of
Uncertainty in Measurement, 1993
– NIST TN 1297, Guidelines for Evaluating and
Expressing Uncertainty of NIST Measurement
Results, Barry N. Taylor and Chris E. Kuyatt, 1993
– NAMAS M 3003 “The Expression of Uncertainty
and Confidence in Measurement,” December 1997
– SINGLAS TECHNICAL GUIDE 1 “Guidelines on
the evaluation and expression of the measurement
uncertainty,” July 1995
* Selected by the author
ISO/IEC 17025 Differences:
5.5 Equipment
• More definitive than Guide 25 in some areas:
– up-to-date instructions on use and maintenance
– couples software control to equipment issues
– couples between-calibration checks with equipment
issues
• A2LA Calibration Program requires unique
identification of measuring instruments for
tracking calibration and maintenance (e.g.,
asset numbers, or equivalent identifications)
ISO/IEC 17025 Differences:
5.6 Measurement Traceability
• More definition in following areas:
– Wherever possible, traceability to SI units of
measurement
– Suggests traceability through calibration laboratories accredited to 17025
• Both A2LA & NVLAP require traceability
through accredited calibration laboratories
• A2LA Calibration Program requires formal
establishment of calibration intervals*
*this requirement presented earlier
ISO/IEC 17025 Differences:
5.7 Sampling
• Requires sampling plan when sampling
• Not really germane to calibration laboratories
ISO/IEC 17025 Differences:
5.8 Handling Test & Calibration Items
• Less stringent with respect to recording
condition of test item when abnormalities are
not found on incoming inspection
• A2LA Calibration Program requires two
distinct work areas for:
– Receiving and cleaning, and
– Calibration where measurement standards are
maintained
ISO/IEC 17025 Differences:
5.9 Quality Assurance/Control
• Incorporates Guide 25 clause 5.6 and requires
monitoring of results by the following:
– use of certified and/or secondary reference materials
– participation in interlaboratory comparison or
proficiency testing programs
– replicate testing/calibrations
– re-calibration or re-testing of retained items
• ANSI/NCSL Z540-1 & Guide 25 requires same*,
but also suggests use of statistical techniques
*Note A2LA Calibration Program
requirement
Calibration Laboratories:
Proficiency Testing
• Both A2LA & NVLAP require that calibration
laboratories participate in initial and annual
calibration of artifacts
• NVLAP normally requires three artifacts per optical
radiation field
• Typically, A2LA requires two to three measurement
audits per year
• Both evaluate a calibration laboratory’s proficiency test
results based on a formula that indicates the lab’s
deviation from the associated reference measurement
results and the associated measurement uncertainty
Calibration Laboratories:
Typical Artifacts In Proficiency Testing
Optical Field
Artifact/Reference Device
• Photometry
• Spectrophotometry
• Pyrheliometry and
Pyranometry
• UV Radiometry
• Standard Lamps (NIST)
• SRMs or MAPs* (NIST)
• Pyrheliometers &
pyranometers (WRR^)
• Reference Radiometers
(NIST)
• Regulated Lamps (NIST)
• Reference Detectors
(NIST)
• Spectral Irradiance
• Spectral Responsivity
*MAP = Measurement Assurance Program
^WRR = World Radiometric Reference
ISO/IEC 17025 Differences:
5.10 Reporting Results
• Simplifies Guide 25 reporting requirements for
internal calibrations
• Evidence of traceability on calibration certificates, e.g., logo of accrediting body
• Certificates must not contain recommendations
of calibration interval except when agreed upon
with client
• Permits inclusion in reports and certificates of
interpretations of results
Other Resource Documents
• ANSI/NCSL Z540-1-1994, Calibration Laboratories and
Measuring and Test Equipment - General Requirements
• ISO 10012-1 (1993) Quality assurance requirements for
measuring equipment - Part 1: Metrological confirmation . .
• A2LA Calibration Program Requirements (April 1995)
• A2LA Proficiency Testing Requirements for Accredited
Testing and Calibration Laboratories (1999)
• NVLAP Technical Guide for Optical Radiation Calibrations,
James L. Cigler et al, Nov. 1993
• Peter J. Unger, ISO/IEC 17025 Differences with Guide 25