Specifications and Tolerances for Reference Standards and ...

1 National Institute of Standards and Technology Department of CommerceNIST Handbook 105-1 Specifications and Tolerances for Reference Standards and FieldStandard Weights and MeasuresThis publication is available free of charge from: and Tolerances for Field Standard Weights This publication is available free of charge from: INSIDE FRONT COVER - BLANK This publication is available free of charge from: Specifications and Tolerances for Reference Standards and Field Standard Weights and Measures Specifications and Tolerances for Field Standard Weights Editor: Val R. Miller Dr. Douglas Olson, Chief Office of Weights and Measures Physical Measurement Laboratory This publication is available free of charge from: May 2019 Department of Commerce Wilbur L. Ross, Secretary National Institute of Standards and Technology Dr.

2 Walter Copan, NIST Director and Under Secretary of Commerce for Standards and Technology NIST Handbook 105-1 May 2019 References 1990 Edition for Field Standards in service prior to January 1, 2020. This publication is available free of charge from: Certain commercial entities, equipment, or materials may be identified in this document to describe an experimental procedure or concept adequately. Such identification is not intended to imply recommendation or endorsement by the National Institute of Standards and Technology, nor is it intended to imply that the entities, materials, or equipment are necessarily the best available for the purpose. National Institute of Standards and Technology Handbook 105-1, 2019 Edition Natl. Inst. Stand.

3 Technol. Handb. 105-1, 2019 Ed., 13 pages (May 2019) GOVERNMENT PRINTING OFFICE WASHINGTON For sale by the Superintendent of Documents, Government Printing Office, Washington, DC 20401-9325 NIST Handbook 105-1 Page iv May 2019 This publication is available free of charge from: Preface NIST Handbook 105-1 contains Specifications and Tolerances establishing minimum requirements for Standards used by State and local Weights and Measures officials in the regulatory verification of scales and other weighing devices used in quantity determination of materials sold by weight. Other users may find this handbook helpful in the design of field standard weights, but the requirements should not be considered mandatory for special applications outside of the scope of regulatory Weights and Measures.

4 Document History and Changes NIST Handbook 105-1 has been updated infrequently. The three most recent revisions prior to this edition were completed in 1969, 1972 and in 1990. In each revision changes were made to address issues that had been identified since the prior revision. Weight designs, materials, and Tolerances were some of the changes. In this 2019 edition, NIST Handbook 105-1 directs the user to a much broader choice of mass Standards that must be properly selected to ensure full compliance with NIST Handbook 44 Appendix A Fundamental Considerations is maintained. The commercial weighing marketplace is changing, and increased use of Class I and Class II commercial weighing devices indicates that the Tolerances originally identified in NIST Handbook 105-1 (approximately % of nominal) are no longer adequate for the testing of all commercial weighing systems.

5 Mass Standards of accuracy classes such as OIML R111 Class F1 and ASTM E617 Class 2 are increasingly required for calibration of some commercial weighing systems. As NIST Handbook 105-1 identifies the mass Standards that are suitable for Weights and Measures field use, and ASTM E617 and OIML R111 both identify a wide range of mass standard Tolerances , users are now directed to those documentary Standards for selection of field standard weights. The 1990 edition of NIST Handbook 105-1 will be maintained as written in 1990 and made available by NIST Office of Weights and Measures upon request, to provide historical Reference for calibration of NIST Class F weights placed in service prior to January 1, 2020. NIST Class F field Standards should not be procured for legal metrology (Weights and Measures) use after January 1, 2020.

6 NIST Handbook 105-1 Page v May 2019 This publication is available free of charge from: Table of Contents Introduction .. 1 1 Scope .. 1 Field Standard Classification .. 1 Retroactivity .. 1 Future Designs .. 2 2 Reference Documents .. 2 American Society for Testing and Materials (ASTM) .. 2 International Organization of Legal Metrology (OIML) .. 2 National Institute of Standards and Technology (NIST), Office of Weights and Measures (OWM) .. 2 3 Terminology .. 3 4 Specifications .. 3 Physical Size .. 4 Size Declaration .. 4 Identification Markings .. 4 Material .. 4 Construction .. 4 5 Tolerances (Maximum Permissible Errors) .. 4 6 Verification Requirements .. 4 Legal Requirements .. 4 Traceability .. 5 Calibration Certificates .. 5 Initial and Periodic Verification .. 5 7 Test Methods and References.

7 5 8 Uncertainties .. 6 Legal Applications .. 6 Excerpt from Handbook 44 - 2019 .. 7 NIST Handbook 105-1 Page 1 May 2019 This publication is available free of charge from: Specifications AND Tolerances FOR Reference Standards AND FIELD STANDARD WEIGHTS AND MEASURES 1. Specifications and Tolerances for Field Standard Weights These Specifications and Tolerances establish the minimum requirements for Field Standards used by State and local Weights and Measures officials and others in the regulatory verification of weighing devices used in quantity determination of commodities sold by weight. Non-Weights and Measures users may find this handbook helpful in the design of field standard weights, but the requirements should not be considered mandatory for special applications outside of the scope of regulatory Weights and Measures.

8 Key words: field standard weight, weight, standard, NIST Class F, tolerance , maximum permissible error. Introduction Field standard weights are used primarily to test commercial weighing devices for compliance with commercial requirements. Use of these field Standards at all appropriate levels of manufacture, distribution, and Weights and Measures inspection will help promote accuracy and uniformity in commerce. The breadth of topics in this handbook is intended to provide information for manufacturers, calibration staff, Weights and Measures officials, and other end users. References are provided when additional information may be useful to the reader. 1 Scope Field Standard Classification These Specifications and Tolerances are limited to Field Standard Weights.

9 The field Standards covered by this publication are intended to be used by Weights and Measures officials. Manufacturers and distributors of scales, load cells, and other weighing devices may find these Specifications and Tolerances useful. Use of these Standards at all appropriate levels of manufacture, distribution, and Weights and Measures inspection will help promote accuracy and uniformity in commerce. The terms weight , mass standard , and mass as used in this publication refer to all sizes in general. Customary units will be used hereafter to reflect the nominal masses in common usage in the United States. Retroactivity These Specifications are not intended to make obsolete those field Standards manufactured to comply with NIST Handbook 105-1 (1990). However, all new field standard weights placed in service after January 1, 2020, must meet the requirements of Handbook 105-1 (2019) prior to approval for regulatory Weights and Measures (legal metrology) use.

10 Field standard weights manufactured to meet prior Specifications may be used provided they 1) comply with the applicable NIST, ASTM, or OIML requirements, 2) maintain the specified Tolerances , 3) their performance is adequate to meet NIST Handbook 44 fundamental considerations NIST Handbook 105-1 Page 2 May 2019 This publication is available free of charge from: ( , the correction plus the measurement uncertainty does not exceed one-third of the tolerance for the device being tested). Existing NIST Class F field Standards are considered acceptable for use when the requirements of the Fundamental Considerations are met (normally Class III, IIIL, and IV weighing devices. NOTE: NIST Handbook 105-1 (1990) will be maintained and provided by NIST Office of Weights and Measures (OWM) upon request to provide historical perspective and to ensure that design and tolerance information is maintained for field Standards that were manufactured and procured to that version of this specification .