by Paul Ingallinera

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.

Current calibration requirements

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 ISO/IEC 17025-accredited.

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.

Technical competence

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 documents.

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.

Scope of accreditation

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.

Common accreditation pitfalls

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.

Choosing an accreditation body

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 accredited laboratories.

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.

Measurement uncertainty and hidden requirements

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.

Registrars and affiliates

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 accreditation body.

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 include:

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.

In conclusion

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.

About the author

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 Inc. Letters to the editor about this article can be sent to letters@qualitydigest.com.