NIST Seminars

This seminar provides an overview and and details of time and frequency metrology. It focuses on fundamental concepts, measurement techniques, metrological traceability, and data and measurement uncertainty analysis. Lecture topics covered will include: · Fundamentals of Time and Frequency and basic terminology · Quartz Oscillators · Atomic Oscillators (rubidium, cesium, and hydrogen maser) Laboratory Instrumentation · Measuring Frequency Accuracy in the Time Domain Estimating Stability with the Allan deviation and related statistics · Stopwatch and Timer Calibrations Traceability · Uncertainty Analysis for time and frequency calibrations · GPS/GNSS and GNSS-Disciplined Clocks and Oscillators · The Network Time Protocol (NTP) · Applications of Time and Frequency Measurements (telecommunications, electric power, stock market trading) For additional technical information, contact Andrew Novick (303) 497-3378 or novick@nist.gov

This NIST short course covers the propagation of measurement uncertainty using the methods outlined in the JCGM Guide to the Expression of Uncertainty in Measurement from a statistical perspective. The short course will provide participants with a working knowledge of the computational methods needed to assess measurement uncertainty, hands-on experience in the application of these methods, and scientific and statistical insight into the interpretation of the results. The Hands-on Workshop on Assessing and Reporting Measurement Uncertainty is a 2-day course that will be held at the Measurement Science Conference in Anaheim, CA. The course consists of lectures, short exercises, and hands-on applications covering many aspects of the propagation of uncertainty using examples from NIST work. The exercises and hands-on applications will use functions for uncertainty analysis from the software package, metRology, written for the open-source R statistical computing environment, as well as the web-based NIST Uncertainty Machine (NUM). Participants should bring their own laptops, if possible. A laptop for use during the short course can be provided (sharing may be required). If you would like to borrow a laptop, please let one of the instructors know as soon as possible. All software except Microsoft Excel is free. Topics Covered Importance of uncertainty analysis Different statistical approaches and tools for uncertainty analysis Measurement functions Type A and Type B methods for evaluating standard uncertainties Degrees of freedom Sensitivity coefficients Propagation of standard uncertainties Monte Carlo simulation Expanded uncertainties Interpretation and reporting of results

This full day tutorial will cover the fundamentals of internal auditing based on the ISO 19011:2026 Guidelines for auditing management systems standard. The course will also include the applicable requirements of ISO/IEC 17025:2017 General requirements for the competence of testing and calibration laboratories, so you can ensure that you have a solid audit program in place that complies with your accreditation body and/or customer requirements. The course will start with general auditing principles and will cover critical auditing elements such as audit planning, preparation, conduct, key auditor attributes, audit techniques, documentation of audit findings, and audit closing activities. A critical element in the operation of every laboratory is metrological traceability. This course will delve deeper into the specifics of how to appropriately audit metrological traceability and the associated requirements of the ISO standards, customer requirements, and/or the requirements of your accreditation body. The tutorial will define what metrological traceability is, what requirements need to be considered, and how you specifically audit your laboratory to ensure you have appropriate metrological traceability. Without metrological traceability, you can’t have confidence in your measurement results. You can’t just rely on a statement that results are traceability to the international system of units (SI) as your means of auditing metrological traceability. This course will help you to confirm that you have appropriately established metrological traceability to support the results that are provided to your customers. The tutorial will include instruction, group exercises, and group discussions. Learning Objectives: List at least two reasons for performing an internal audit Describe at least five attributes of an effective auditor Describe the internal audit planning and process Identify objective evidence Explain the concepts of metrological traceability Compare calibration certificates against requirements of ISO/IEC 17025 Use auditing tools to demonstrate the chain of traceability

At the National Institute of Standards and Technology (NIST), the U.S. representation of the ohm is based on the quantum Hall effect, which is maintained and disseminated at various resistance levels by working reference groups of standards. NIST provides a calibration service for standard resistors with nominal decade values in the range of 10−4 Ω to 1013 Ω. High-current standard resistors, known as shunts, with nominal values as low as 10−5 Ω can be calibrated at currents as high as 3000 A. This tutorial will cover the fundamentals of DC resistance metrology with the aim of providing knowledge and measurement techniques to assist metrologists in making accurate and reliable DC resistance measurements. The art of resistance metrology will be explained beginning with the quantum Hall effect that serves as the basis of the US representation of the ohm and the measurement techniques and instrumentation used in scaling and disseminating resistance at different decade levels from the quantum Hall resistance standard. The effects of pressure, temperature, voltage, drift, and current on resistor measurements will be explained and methods will be shown how to account for these parameters. An uncertainty budget will be built to demonstrate key elements that affect a resistor’s measured value at different decade levels.

Making good pressure measurements from high pressure hydraulic to ultra-high vacuum requires knowing what gauge to use. Common gauge types include: ionization gauges, spinning rotor gauges, thermal conductivity gauges, capacitance diaphragm gauges, quartz bourdon tube gauges, resonant silicon gauges, MEMS, and piston gauges. However, knowing what gauge to select can save time and money along with prevent measurement errors. Even the best gauge, if used incorrectly can cause errors that cost time/money and can result in dangerous situations. This two-day course will cover the fundamentals of pressure measurements from 10^-8 Pa to 10^+8 Pa, focusing on the selection and proper use of appropriate gauging technology for a given application. A survey of calibration techniques will be presented along with recommendations for obtaining best performance. Part of the class time will be devoted to set-up of a simple vacuum calibration system and a piston gauge calibration setup. This will enable hands-on learning of some of the gauges discussed in the course and give students an opportunity to participate in the system set-up and disassembly. We will also provide an overview of system design and construction including pumping systems, sealing, valves, fittings, and pressure lines. Attendees are invited to share their own pressure measurement and or vacuum system design problems for in-class discussion.

Fundamental measurement concepts are presented as applicable for any field of metrology: Who’s Who in Metrology and Accreditation, SI Basis for Measurements, Essential Elements of Traceability, Method Validation (Documented Procedures), Technical Competence (Proficiency Testing), Calibration Intervals, Measurement Assurance, Measurement Uncertainty, Calibration Certificates and Evaluations, Supplier Evaluation, and Assessing Traceability. Several sections will discuss risk management philosophies and approaches. Participants will obtain and know how to use several simple tools, job aids, and references to improve laboratory operations. This session is applicable for participants new to metrology, new to metrology management, as a refresher of fundamental concepts with a high level view, or for anyone responsible for providing on-the-job training to new metrologists to help identify key concepts and prepare someone new to metrology for a successful career. Activities and quizzes are integrated into each module with full participation expected. Participants must bring 4 documents that will be integrated in evaluation activities: 1) an example of a calibration certificate from their own laboratory (redacted if needed), 2) a calibration certificate from a supplier/vendor, 3) the laboratory Scope for the participant’s laboratory and 4) the laboratory Scope from the supplier/vendor of the certificate brought as item 2. Specific NIST OWM procedures that are referenced are posted here (https://www.nist.gov/pml/weights-and-measures/laboratory-metrology/calibration-procedures) and include: GMP 11, GMP 13, GLP 1, SOP 1, SOP 29, and SOP 30; pre-work reading and familiarity is a good idea. Note: this is a two-day course, with no specific measurement applications, and while similar to, it is not in alignment with the NIST OWM 5-day Fundamentals of Metrology seminar, is not a substitute for the successful completion of that seminar and will not meet subsequent course pre-requisites (such as the NIST Mass Seminar or Volume Seminar). See the full course, Table of Contents and examples of detailed learning objectives for overlapping topics that will be covered here: http://www.nist.gov/pml/wmd/labmetrology/fundamental-metrology.cfm. At the end of this session, participants will be able to: identify and use reference materials to ensure quality, accurate, and traceable measurement results; explain highlights and key concepts of each topic to each other and to your managers and demonstrate how these topics fit in to a management system using ISO/IEC 17025:2017 as the basis.

The 2019 redefinition of the International System of Units has opened the door to a new era of mass and torque realization. The definition of the kilogram is no longer a platinum-iridium cylinder locked away in a vault in France but is instead tied to the precisely defined value of Planck’s constant. This extended seminar will discuss how the Planck constant gives us the definition of the kilogram, ramifications of the redefinition, and how this new definition can be used to potentially revolutionize mass and torque metrology using the Kibble principle. Two projects from the National Institute of Standards and Technology; the tabletop Kibble balance project (Kibb-g2) and the Electronic NIST Torque Realizer (ENTR) will be used as examples of the leading edge of Kibble-based realization of mass and torque metrology, offering a window into the future of mass and torque standard dissemination.