Preface

NIST manages the State Laboratory Program that began with the New State Standards Program established by Congress in 1965 as part of its continuing support to the States. This program of the NIST Office of Weights and Measures (OWM) is designed to provide guidance, technical support, and assistance to State legal metrology laboratories to ensure accurate and traceable measurements from NIST to the local jurisdictions. The program operates through continued partnership with the State laboratories to manage numerous measurement-related activities.

Significant changes have been made to the program of recognition for the States and to this Program Handbook since the first edition was published in 1985. The program has incorporated national and international standards; though OWM does not provide formal accreditation according to ISO Guide 58, and the program is operated independently from the National Voluntary Laboratory Accreditation Program (NVLAP), the general and technical criteria used in both programs are identical. The following list shows key changes in this edition of the Handbook:

• Information associated with the National Type Evaluation Program (NTEP) is no longer covered in this program handbook.
• Parts 3 and 4 are policy and procedure information specific to OWM operations and recognition process; Figure 1 is a flow chart showing the recognition process.
• Parts 5 and 6 incorporate ANSI/NCSL Z540-1-1994 (parts I and II) with NVLAP additions and OWM NOTES. These sections are included as Subpart D in NIST Handbook 150, NVLAP Procedures and General Requirements. OWM NOTES added to parts 5 and 6 are additional policy or requirements that apply generally to all legal metrology laboratories without regard to recognition level.
• Part 7 is taken from the NVLAP Calibration Laboratories Draft Technical Guide, but has been edited for publication. OWM and the National Conference on Weights and Measures (NCWM) ISO 9000 Task Force prepared the mass and volume sections, and reviewed them at a special NVLAP workshop in December 1992 (mass criteria only), at a NVLAP workshop in November 1993, and at all six regional metrology meetings in 1993, 1994, and at the 1994 NCWM meeting. Laboratories performing temperature measurements were given the opportunity to review the temperature section. Diane Lee (NIST) prepared the moisture section; it was reviewed at the Southeastern Measurement Assurance Program (SEMAP) regional metrology meeting in 1993.

Since the July 1996 edition was published, changes were made in the OWM State Laboratory Program by NIST management. As a result, this Handbook was revised to delete references to accreditation. References to "accreditation" were replaced with references to "recognition," references to a "certificate of accreditation" were replaced with references to a "Certificate of Traceability," and references to the OWM State Laboratory Program as an "accreditation program" were replaced with references to a "measurement assurance program."

Note regarding SI units:
Appropriate SI units of measure have been used throughout this document where possible. Since commercial applications in the United States use units other than SI or other accepted metric units, this document may reference other common units in current use.

Acknowledgments and History

This Program Handbook, first published by Henry V. Oppermann and John K. Taylor in 1985, documented and formalized the certification program whereby NIST recognized the capabilities of State legal metrology laboratories. Prior to that time, the NIST Office of Weights and Measures issued "Certificates of Participation" to States participating in the program. In 1985, OWM started certifying laboratories against the criteria in Handbook 143, Program Handbook. The 1985 criteria were based on International Standards Organization (ISO/IEC) Guide 25 (1982), General Requirements for the Competence of Calibration and Testing Laboratories.

The Office of Weights and Measures began the process of updating this Program Handbook in 1991. Due to the many activities related to ISO 9000 in the United States and questions regarding how those activities would impact the State laboratories, ISO standards were circulated to the State laboratories in 1991.

The National Conference of Standards Laboratories (NCSL), Total Quality Management (TQM) Committee also started working on the development and adoption of a single U.S. national standard for calibration laboratories in 1991. The NCSL TQM Committee included representatives from NIST, Department of Defense, Department of Energy, Nuclear Regulatory Commission, Federal Aviation Administration, and numerous industries.

In 1992, the National Conference on Weights and Measures (NCWM) established an ISO 9000 Task Force. After review of the 1985 version of the Handbook and ISO/IEC Guide 25 to determine the conformance status of State laboratories, the group recommended the use of one standard in the United States (consistent with the NCSL position) for the accreditation of calibration laboratories to:

1. reduce the number of redundant laboratory audits;
2. improve measurement compatibility and acceptance of measurement results between laboratories in the United States and internationally; and
3. comply with the ISO-series standards for quality.

The NCSL TQM Committee became an official ANSI standards writing body (Committee Z 540) and published the new U.S. standard as Z540-1-1994 (July 1994). ANSI/NCSL Z540-1-1994 incorporates ISO Guide 25 and Mil-Std-45662A. Since NCSL published this new standard in 1994:

1. the Department of Defense has rescinded Mil-Std-45662A in favor of the Z540-1-1994 standard;
2. the NIST National Voluntary Laboratory Accreditation Program (NVLAP) has adopted and referenced ANSI/NCSL Z540-1-1994;
3. the American Association for Laboratory Accreditation (A2LA), a private accrediting body, has also adopted the standard; and
4. the NIST Office of Weights and Measures, has incorporated the standard into Parts 5 and 6 of this document. Additional requirements consistent with NVLAP requirements and with the needs of the legal metrology system are included.

In 1997, NIST management made the decision that NIST would operate only one formal accreditation program: the National Voluntary Laboratory Accreditation Program (NVLAP). Therefore, all references to accreditation by OWM were changed to recognition and OWM ceased issuing of Certificates of Accreditation. How these changes will impact the level of uniformity in the States is unknown at this time; however, OWM intends to monitor the level of State compliance to this Handbook and other laboratory quality standards to ensure adequate accuracy, traceability, and uniformity are maintained in State weights and measures laboratories.