Directory of Accredited Calibration Laboratories

Indexed by Field of Calibration

The Calibration Laboratories Accreditation Program was established in response to a request from the National Conference of Standards Laboratories (NCSL). Under the Calibration Laboratories LAP, laboratories are accredited to perform calibrations, at specified ranges and uncertainties, in one or more of the eight fields of calibration covering in excess of eighty parameters. To become accredited, laboratories must meet the requirements set forth in NIST Handbook 150, NVLAP Procedures and General Requirements. The NIST Handbook 150-2 handbook series for calibration laboratories was developed to assist laboratories in achieving accreditation by providing guidelines for good calibration laboratory practices. Click here to view the list of NVLAP handbooks in this series.

Calibration laboratories are accredited by NVLAP for compliance with the general requirements of ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories. Laboratories wishing to do so may also be evaluated and recognized for compliance to ANSI/NCSL Z540-1, Calibration Laboratories and Measuring and Test Equipment - General Requirements, Part 1. This will require that the laboratory address those requirements of ANSI/NCSL Z540-1-1994 that are not sufficiently addressed by ISO/IEC 17025. A short checklist is provided at Supplemental Checklist for Verification of Compliance to ANSI/NCSL Z540-1-1994, Part 1.

Notice: All International Laboratory Accreditation Cooperation (ILAC) Mutual Recognition Arrangement (MRA) accreditation bodies (ABs) have been tasked to switch to the terminology, “Calibration and Measurement Capability” (CMC). The consensus of agreement for the definition is broad and is found in the first section of this document,

Furthermore, a recent addition to the ILAC procedural series documents, ILAC-P14 entitled, "ILAC Policy for Uncertainty in Calibration," with an implementation date of November 2011, calls for specific requirements regarding the development and reporting of CMCs. This document may be reviewed at this link, NVLAP has implemented these changes and is making this an opportunity to improve the scopes of accreditation for the calibration laboratories.

Revised calibration scope formats will begin to appear on the NVLAP website effective for the October 2011 accreditation renewal cycle. The remaining revised scopes will appear as the laboratories renew their accreditation in the upcoming year.

The improvements include:

  • Consistent format where headings remain at top of page and column names remain more consistent across different scopes of accreditation;
  • Common notes are consistent across all scopes. Notes related to a specific lab’s uncertainties or capabilities are placed near the information to which they refer to. Example: The common explanation related to field service uncertainties will always be Note 4 on the calibration scope. A note related to “Where L is length in inches” will be near the uncertainty statement to which it relates;
  • 2 significant digits utilized in uncertainty values; and
  • Increased use of SI units, where reasonable.

Index to Accredited Calibration Labs by Field of Calibration

Click on the field of calibration to view a listing of laboratories accredited by NVLAP for that field.

For additional information, contact NVLAP at (301) 975-4016.

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