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NIST Handbook 150-21, NVLAP Chemical Calibration: Certifiers of Spectrophotometric NTRMs



Barbara J. Belzer


NIST Handbook 150-21 presents technical requirements and guidance for the accreditation of laboratories under the National Voluntary Laboratory Accreditation Program (NVLAP) Chemical Calibration (Filter NTRMs) program. It is intended for information and use by accredited laboratories, laboratories seeking accreditation, laboratory accreditation systems, users of laboratory services, and others needing information on the requirements for accreditation under this program. The 2011 edition of NIST Handbook 150-21 incorporates changes resulting from the release of the newest editions of ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories, and NIST Handbook 150, NVLAP Procedures and General Requirements, as well as editorial improvements. The requirements of NIST Handbook 150, the interpretations and specific requirements in NIST Handbook 150-21, and the requirements in program-specific checklists (if applicable) must be combined to produce the criteria for accreditation in the NVLAP Filter NTRMs program.
Handbook (NIST HB) - 150-21
Report Number


accreditation, assessment, chemical calibration, filter NTRMs, laboratory, management system, NVLAP, proficiency testing, testing


Belzer, B. (2011), NIST Handbook 150-21, NVLAP Chemical Calibration: Certifiers of Spectrophotometric NTRMs, Handbook (NIST HB), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 25, 2024)


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Created June 14, 2011, Updated February 19, 2017