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NVLAP NIST Handbook 150-2 New Release

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In October 2024, the National Voluntary Laboratory Accreditation Program (NVLAP) released a revised version of NIST Handbook 150-2, which represents the technical requirements for the accreditation of laboratories under the NVLAP Calibration Laboratory Accreditation Program.  This new release was announced and is available on NVLAP’s Lab Bulletins which is used to inform participating laboratories and interested parties of changes made to the laboratory accreditation program. 

The revised edition received input from NIST technical experts for the represented calibration parameters. The following provides some of the primary updates made to the latest publication:

  • Sections 7.6.2 and 7.8.1 fully reflect the requirements of ILAC P14:2020.

  • Section 7.7.2.1 includes the use of risk-based thinking in the establishment of proficiency testing intervals.

  • Annex D sets out technical requirements not covered in NIST Handbook 150 that are applicable to a laboratory performing mechanical calibrations in the areas of force and mass.

  • Requirements applicable only to legal metrology laboratories have been removed from Annex D with the volume calibrations section removed. 

  • Annex E sets out logistical requirements not covered in NIST Handbook 150 that are applicable to the NVLAP assessment and accreditation of laboratories that are recognized by the NIST Office of Weights and Measures (OWM) and that perform legal metrology as State weights and measures laboratories. There is a new NIST Handbook 143 checklist that has been created and will be used for the assessment of State weights and measures laboratories, which is available in the NVLAP Interactive Web System (NIWS) portal. 

The NIST Handbook 150-2 checklist has also been updated and is available in the NVLAP Interactive Web System (NIWS) Portal, which is accessible to active laboratories or interested laboratories upon request.

NVLAP labs
A map of the NVLAP-accredited state metrology laboratories in 2025.

NVLAP, OWM, and the state metrology laboratories have worked together to establish a program that helps to ensure the validity of measurements that support legal metrology across the USA. NVLAP accreditation to ISO/IEC 17025 is partially supported by OWM for those state metrology laboratories that have achieved OWM recognition. OWM aspires for all state laboratories to hold recognition and accreditation from NIST, with accreditation being the ultimate demonstration of quality for their laboratory metrology program. Interested laboratories should coordinate with OWM and conduct a self-assessment with the NIST Handbook 150-2 and NIST Handbook 143 checklists prior to applying for accreditation. 

Please contact NVLAP Program Manager Rob Knake (robert.knake [at] nist.gov (robert[dot]knake[at]nist[dot]gov)) for questions concerning the revised handbook or the accreditation process and requirements.

Released January 7, 2025, Updated February 4, 2025