For the past 20 years, U.S.
companies have adopted international quality management
systems to improve the quality of their products and services.
During this time, the systems have also evolved and improved,
and they've served as models for other international standards
such as ISO/IEC Guide 25. This article will explore accreditation
issues involving the ISO/IEC 17025 standard, which has been
developed for the calibration and testing industry.
If your company is QS-9000-registered, you're aware that
off-site calibration services must be performed by an accredited
laboratory, specifically, as the standard states, "ISO/IEC
Guide 25-accredited." Because QS-9000 was created and
continues to be maintained by automotive industry experts,
the Automotive Industry Action Group publishes the current
recognized accreditation bodies at www.aiag.org. You may
also contact your QS-9000 registrar for this information;
it's important that the contracted laboratory is accredited
by an organization recognized by your registrar.
ISO/TS 16949 is a new international quality management
standard for automotive suppliers, most of whose calibration
supplier requirements are the same as those found in QS-9000.
However, with ISO/TS 16949, the requirements for internal
calibration are very different: It has adopted some of the
same technical and procedural requirements featured in ISO/IEC
17025. What does that mean for an ISO/TS 16949-registered
organization? Regardless of whether calibration is performed
internally or externally, appropriate calibration procedures
and technical competence must be demonstrated. Technical
competence and procedures are assessed through ISO/TS 16949
audits. Alternatively, proactive organizations can require
that their calibration and/or testing laboratory become
The ISO/IEC 17025 standard is organized into two parts.
The first outlines all the requirements that refer to your
quality management system. The second outlines all the requirements
for "technical competence." When setting up a
new laboratory program, many organizations underestimate
the latter part of the standard. Laboratory accreditation
is quite different from a quality management system. Not
only is an organization's quality management system assessed,
but so are its technical capabilities and competence.
As a rule, recognized accreditation bodies contract experts
in each accreditation field, and they make judgments based
on technical procedures, training records, interviews and
technical personnel performance. They use this information
to determine whether the organization is technically competent
for each item featured on its accreditation scope.
Once a laboratory has been accredited, the certificate
and scope become very powerful credentials. Laboratory accreditation
is one of the easiest ways to prove traceability to a national
or international standard. When a lab goes through its initial
and surveillance assessments, one of the primary topics
examined is traceability. If the lab passes, its clients
can be assured that all accredited calibration and/or testing
processes are traceable to a national or international standard.
During an ISO/IEC 17025 assessment, technical competence
must be demonstrated. This usually begins with appropriate
calibration and/or testing procedures. These represent the
basis for the calibration and testing processes; therefore,
it's essential that they include factual technical content
and are based on nationally or internationally accepted
For example, a gage block calibration procedure should
include details about the block type, environmental conditions,
calibration equipment, tolerances and every step of the
method. Additionally, this procedure should be based on
details featured in the current ASME B89.1.2M national standard.
Once your procedures are appropriate, you must effectively
communicate them to your technicians through training--critical
for process consistency, expertise and communication to
the client. Any time training occurs, it should be documented.
The ISO/IEC 17025 assessor will evaluate many aspects
of your technical program. He or she will interact with
the technicians, gathering necessary competence information,
and will expect each technician to not only perform calibration
and/or testing methods correctly but also understand why
particular methods are followed. Additionally, the assessor
will analyze training records for competence information.
During the accreditation process, your accreditation body
is required to approve and issue a "scope of accreditation."
This is a supplementary certificate document that outlines
your lab's technical capabilities. Labs are required to
document each calibration or testing parameter, parameter
range, the best measurement uncertainty for each parameter
and the calibration/testing equipment or standard(s) used
for each parameter. If this process isn't completed within
accreditation-body requirements, it could delay initial
or surveillance accreditation. Furthermore, the best measurement
uncertainty featured on your scope must be accepted by your
accreditation body from a technical perspective. Inappropriate
uncertainties can also delay accreditation.
Scopes of accreditation can be useful tools in comparing
accredited laboratories; however, inconsistencies do exist.
Overall, labs are required to represent their capabilities
honestly on their issued scope.
Whether you're establishing a new accreditation program
or simply transitioning, there are some common pitfalls
every lab should be aware of. The most common is measurement
uncertainty. It's important that appropriate members of
your organization learn how to calculate and apply measurement
uncertainty to your processes. Keep in mind that measurement
uncertainty isn't a concept that should be linked to an
instrument or piece of equipment. Rather, it's associated
with a calibration, inspection or testing process. Furthermore,
all calculated measurement uncertainty values should reflect
your lab's true capabilities. Many laboratory accreditations
are delayed because measurement uncertainty and best measurement
capability values don't reflect accurate capabilities.
Another common pitfall is traceability when using an external
calibration laboratory. The ISO/IEC 17025 standard states,
"When using external calibration services, traceability
of measurement shall be assured by the use of calibration
services from laboratories that can demonstrate competence,
measurement capability and traceability." The standard
further notes that a "competent laboratory" is
one that can fulfill all the requirements featured in the
ISO/IEC 17025 standard. There are two ways of proving competence:
Use a laboratory that's accredited by a recognized accreditation
body, or have the laboratory formally assessed by ISO/IEC
17025 technical experts.
The accreditation body you choose is critical. Accreditation
bodies are not all the same, nor do they simply follow the
requirements featured in the ISO/IEC 17025 standard. Most
have additional program requirements. It's essential that
you fully research all the requirements published by the
accreditation bodies. For example, the Laboratory Accreditation
Bureau publishes a special program requirement that obligates
contracted external calibration labs to be accredited by
the LAB, or an organization that's pursuing membership or
belongs to the National Cooperation for Laboratory Accreditation.
When it comes time to contract or subcontract measuring
equipment, this requirement will give you many choices of
The American Association for Laboratory Accreditation,
another popular accreditation body, publishes a similar
traceability program requirement. However, its version ultimately
limits the number of accredited calibration laboratories
you can use. You must fully research each accreditation
body that appeals to you because some of their special program
requirements might not conform to your type of business
or operating philosophy.
Also consider why you want to become accredited. If you
choose one that's not currently recognized by NACLA or isn't
pursuing membership, this could become an issue if you're
a commercial calibration laboratory. Currently, some labs
are having problems keeping or gaining business from other
calibration laboratories accredited by an NACLA-recognized
accreditation body. However, if the nature of your business
doesn't involve commercial calibration (i.e., because you
use an internal calibration laboratory), you may have fewer
problems when selecting and maintaining your system.
Any laboratory pursuing ISO/IEC 17025 accreditation must
be aware of the inconsistencies of measurement uncertainty
within the accreditation community. As stated before, measurement
uncertainty is the
No. 1 pitfall; however, additional confusion is contributed
by accreditation bodies.
When measurement uncertainties are to be determined, the
first question asked should be, "Measurement uncertainty
of what?" Accreditation bodies haven't yet established
specific requirements of what measurement uncertainties
should represent. Some accreditation bodies have established
best measurement uncertainty requirements for scopes of
accreditation, but most calibration labs display measurement
uncertainty on issued certificates or reports as well. In
most cases, reported uncertainties on certificates or reports
are extremely inconsistent. Some uncertainties represent
the best measurement uncertainty, some the worst measurement
uncertainty and some the test-point measurement uncertainty.
You should also be aware of hidden requirements in ISO/IEC
17025. One of the most common is 5.9, Assuring the Quality
of Tests and Calibration Results, specifically, Subsection
B, Participation in interlaboratory comparison or proficiency-testing
programmes. Most accreditation bodies are very particular
about the type of proficiency programs in which your lab
participates. Subsection B also requires that the proficiency
organization with which you work conduct its activities
within compliance to ISO/IEC Guide 43. Working with any
other organization can lead to noncompliance.
Not just any organization can become a recognized accreditation
body; it's a difficult international process. If your lab
is currently registered to ISO 9001 and is interested in
becoming accredited, be careful of registrars that claim
they can accredit and register your lab. Quality system
registrars aren't the same as accreditation bodies. Most
registrars that fulfill the accreditation services are known
as affiliates and work directly with recognized accreditation
bodies. Accreditation assessments are done through a subcontracted
As with quality management systems, laboratory accreditation
programs aren't sponsored by the United States alone. However,
the United States is the only country in the international
accreditation community that allows private accreditation
bodies. Organizations such as the LAB and National Quality
Assurance provide accreditation services within a booming
laboratory market. In Europe, all labs seeking accreditation
have only one service from which to choose, usually a government-driven
organization. Other international accreditation organizations
International Laboratory Accreditation Cooperation, www.ilac.org
Asia Pacific Laboratory Accreditation Cooperation, www.ianz.govt.nz/aplac
European Cooperation for Accreditation, www.european-accreditation.org
Interamerican Accreditation Cooperation, www.ibpinetsp.com.br/iaac
National Cooperation for Laboratory Accreditation, www.nacla.net
These international organizations are made up of many
accreditation bodies from different countries. They provide
each other with what are referred to as mutual recognition
agreements. MRAs are the current international method of
assessment for participating accreditation bodies. As the
European Cooperation for Accreditation states, "Through
the multilateral agreement, a uniform level of competence
of the accredited bodies involved is assured, and the need
for multiple assessments is diminished or eliminated."
Additionally, these international organizations provide
consistency of accreditation requirements.
Laboratory accreditation shouldn't be taken lightly. For
most calibration and testing organizations, accreditation
is quite a difficult status to achieve. Preparation is the
key to success; therefore, fully research the recognized
accreditation bodies, inquire about hidden and special program
requirements, and educate your organization about all aspects
and related standards of ISO/IEC 17025.
Paul Ingallinera is a calibration consultant and ISO/IEC
17025 assessor for the Laboratory Accreditation Bureau.
He also conducts calibration, accreditation and measurement
uncertainty training seminars for Nationwide Gage Calibration
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