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2 min read


by Jeremy Kraft, Sr. Manager, Metrology

Recently, the question of what differentiates A2LA, ANAB, and NVLAP has arisen. While researching these 'big three' metrology accreditation bodies, we identified various distinctions and parallels.  A2LA, or the American Association for Laboratory Accreditation, is a not-for-profit and internationally recognized accreditation body. It is among the largest in the world, with a vision of 'Accreditation accepted everywhere.'  ANAB, or the ANSI National Accreditation Board, is a not-for-profit organization and the largest accreditation body in the United States. ANAB is a subsidiary of ANSI and resulted from a merger between the American Society for Quality (ASQ) and the American National Standards Institute (ANSI).  NVLAP, or the National Voluntary Laboratory Accreditation Program, is an agency run by the National Institute of Standards and Technology (NIST). Serving primarily North America, this agency is a part of the United States Federal Government and prides itself on setting the standard for accreditation. 

While all three are internationally recognized by the International Laboratory Accreditation Cooperation (ILAC), there are some key differences. Let’s dive deeper into the distinct features of each: 

• A2LA and ANAB are independent, non-government agencies, while NVLAP is a part of the U.S. Government.
• A2LA and ANAB offer a broad range of accreditations, while NVLAP specializes in specific technical areas.
• A2LA and ANAB have an extensive geographical reach.
• A2LA may recommend an optional Pre-Assessment for new laboratories, allowing the lab to evaluate potential non-conformities before the audit.
• All ANAB Accreditation Managers and Assessors have laboratory experience, either in Calibration or Testing.
• NVLAP might be recognized, preferred, or required for certain programs. For instance, if you're operating under a federal contract, there may be specific traceability requirements to NIST for disciplines, such as Mass Determination.
In addition, all three bodies have their own training and educational resources which can guide you on your path to accreditation: 
• A2LA (now A2LA WorkPlace Training) provides a wide range of training courses ranging from understanding ISO 17025 to calibration, and auditing.
• ANAB offers training (like A2LA WorkPlace Training), including courses on ISO 17025, management systems, and assessor training.
• NVLAP provides focused in-depth metrology courses with NIST experts. Being part of NIST, NVLAP has additional technical expertise and research to specific disciplines.
For some, audits are stressful. Audits are not easy, and your hard work is judged by leading metrology experts. However, by taking the pre-audit preparation, training, and audit process as a learning experience, you will see your staff and technical experience grow into a world-class lab.  In the world of metrology, choosing the right accreditation body is crucial. Always make an informed decision based on the unique needs of your operation. 
Masy Bioservices, an Alcami company, is an ISO 17025 accredited organization. We offer a broad range of Accredited Metrology and Calibration Services, along with dedicated customer support. Contact for consulting or a quote.

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