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COURSES STARTING MONDAY


N01 HANDS-ON WORKSHOP ON ASSESSING AND REPORTING MEASUREMENT UNCERTAINTY

3 DAY COURSE: 

Monday, November 15th, Tuesday, November 16th & Wednesday, November 17th

Presenters: Will Guthrie, NIST, Statistical Engineering Division and Hung-Kung Liu, NIST, Statistical Engineering Divison
For additional technical information contact Will Guthrie at william.guthrie@nist.gov

Abstract

Abstract: 

Purpose 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.

Agenda The Hands-on Workshop on Assessing and Reporting Measurement Uncertainty is a 3-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. The functions can be accessed directly in R (use of RStudio is recommended), or via an Excel graphical user interface that is available as a free Add-In, metRology for Microsoft Excel[1]. 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 for uncertainty analysis
    • – Essentials of the GUM approach
      • – Measurement functions
      • – Type A and Type B methods for evaluating standard uncertainties
      • – Degrees of freedom
      • – Sensitivity coefficients
      • – Propagation of standard uncertainties
      • – Effective degrees of freedom
      • – Expanded uncertainties
    • – Software for propagation of uncertainty
    • – Interpretation of results

Seminar Developers Biography

Seminar Developers Biography: 

William Guthrie - MSCWilliam F. Guthrie received a B.A. degree in mathematics from Case Western Reserve University in Cleveland, OH, in 1987 and an M.S. degree in statistics from The Ohio State University in Columbus, OH, in 1990. He is currently a mathematical statistician in the Statistical Engineering Division at the National Institute of Standards and Technology (NIST) in Gaithersburg, MD. Since joining NIST in 1989, he has collaborated with scientists and engineers on applied research in a wide range of areas including semiconductor and microelectronics applications, building materials and fire research and chemical science. His statistical interests include uncertainty assessment, Bayesian statistics, design of experiments, calibration, modern regression methods, and statistical computation.

 

Hung-Kung Liu - MSCHung-kung Liu is a statistician with experience in consulting on a wide variety of problems applied to engineering and physical sciences.  He is knowledgeable in various approaches to statistical inference, design of experiments, and computer intensive methods with experience in developing statistical methodology for special problems.

Hung-kung Liu joined the National Institute of Standards and Technology in 1991.  Before that he was a faculty member of the State University of New York at Stony Brook since 1984.


N02 NIST PRESSURE AND VACUUM MEASUREMENT

2 DAY COURSE: 

MONDAY, NOVEMBER 15th & TUESDAY, NOVEMBER 16th

Presenters: Jacob Ricker and Christopher Meyer, NIST, Thermodynamic Metrology Group
For additional information, contact: Jacob Ricker, jacob.ricker@nist.gov and Christopher Meyer, christophermeyer@nist.gov.

Abstract

Abstract: 

Making good pressure measurements from high pressure hydralic 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.

Seminar Developers Biography:

Seminar Developers Biography: 

Jacob Ricker - MSCJacob Ricker, works at the National Institute of Standards and Technology where he develops state of the art vacuum calibration systems and conducts research into the next generation vacuum technology.  Jacob maintains and operates the primary standard for pressure and vacuum measurement in the US and is responsible for calibrating pressure and vacuum gauges at NIST in the range of 10-3 Pa to 360 kPa.

His research is focused on new vacuum measurement methods and improving the accuracy of commercial sensors.  Currently, he is the lead designer on new team working to redefine how we measure pressure, temperature, and length.  This team is creating a new primary standard using a revolutionary quantum measurement method.  He has a B.S. from Penn State University in mechanical engineering and a M.S. in applied physics from Johns Hopkins University.  He started at NIST as a student in 2001, however after graduation, he moved on to calibrate underwater acoustics at the Naval Surface Warfare Center before returning to NIST in 2010.

Christopher Meyer - MSCChristopher Meyer has 30 years of metrology experience working at NIST, working in the areas of temperature, humidity, and pressure standards. He is an honor graduate of Haverford College and received his Ph.D. in physics from the University of California at Santa Barbara. Afterwards, Chris came to NIST as a postdoc, where he and performed acoustic thermometry to obtain some of the most accurate thermodynamic temperature measurements ever made over the range 234 K to 303 K.

He joined the NIST Thermometry Group (Now the Thermodynamic Metrology Group) in 1991. Chris’s first project in this group was to construct a facility to realize the International Temperature Scale of 1990 (ITS-90) over the low-temperature region (0.65 K to 84 K) using 3He and 4He vapor-pressure thermometry, gas thermometry, and platinum resistance thermometry.  Since that time, he has worked in several other areas of thermometry, including wire thermocouples, digital thermometers, light-pipe radiation thermometers, and fluorescence thermometers. Chris has worked in the discipline of humidity since 2000. During this time, he helped develop the current NIST gravimetric hygrometer and the hybrid humidity generator (the US national standard for humidity).  He used the gravimetric hygrometer to validate the performance of hybrid humidity generator and measure thermophysical properties of moist air and moist CO2). Chris has operated the humidity calibration laboratory since 2013. Recently, he spent 15 months working at the International Bureau of Weights and Measures (BIPM), helping develop a manometric system for determination of the amount fraction of CO2 in air. In 2017 Chris entered pressure metrology and he now oversees the NIST piston gauge calibration laboratory.


N03 FUNDAMENTALS OF METROLOGY

2 DAY COURSE: 

MONDAY, NOVEMBER 15th & TUESDAY, NOVEMBER 16th

Presenters: Georgia Harris, NIST
For additional technical information contact: Georgia Harris at g.harris@nist.go

Abstract

Abstract: 

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 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.

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.

Seminar Developer Biography:

Seminar Developer Biography: 

Georgia Harris - MSCGeorgia Harris

Work:

-State of Minnesota, Weights and Measures Division (5 years)

-National Institute of Standards and Technology (30 + years, retired/intermittent)

As a part of her prior NIST responsibilities, Georgia oversaw and provided metrology training at NIST and regional training events and ensured the development and compliance of the training program in the Office of Weights and Measures (OWM) with the International Association for Continuing Education and Training.  Currently, she is responsible for providing knowledge transfer support to new staff in the OWM metrology training program.

Speaking/Awards:

Ms. Harris has published and presented papers and conducted metrology and adult education training throughout the U.S., won best paper awards from MSC, NCSLI, and the American Society for Engineering Education, and has presented papers and conducted training at measurement conferences in Canada, Mexico, South Africa, and Colombia.  She was a NIST liaison to the Measurement Science Conference for NIST Seminars for 12 years and a member of the NCSLI Board of Directors for nearly 20 years, including the position of President.  She has won awards from MSC (1997 Andrew J. Woodington Award), NCSLI (2015 Education and Training Award, 2019 Wildhack Award), ASQ Measurement Quality Division (2011 Max J. Unis Award), two Bronze Medal awards from NIST, and was awarded a Fulbright Specialist grant in 2016.

Education:

-University of Minnesota, Moorhead, Biology/Chemistry (BA)

-Johns Hopkins University, Whiting School of Engineering, Technical Management (MS)


N04 DC RESISTANCE

1 DAY COURSE: 

MONDAY, NOVEMBER 15th

Presenters: Shamith Payagala, Alireza Panna, NIST.
For additional technical information, contact Shamith Payagala at shamith.payagala@nist.gov.

Abstract

Abstract: 

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 1012 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 3000A.

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.

Seminar Developers Biography:

Seminar Developers Biography: 

Shamith Payagala - MSCShamith Payagala received the B.S. degree in electrical engineering from the University of Maryland, College Park, MD, in 2015, and the M.S. degree in electrical engineering from Johns Hopkins University, Baltimore in 2019. In 2014, he joined the National Institute of Standards and Technology (NIST) as a guest researcher from the University of Maryland.  During this time, he worked in the DC high resistance area on the automation of resistance calibration systems. In 2015, he joined NIST full time as an electrical engineer working on improving resistance bridges, standards, & low current techniques in the NIST Metrology of the Ohm Project. His research interests include Direct Current Comparator bridges, improving the repeatability of ultra-high resistance measurements using Dual Source Bridges, Ultra-Low Current Amplifier Systems for low current generation and measurements, advancing capabilities of temperature-controlled chambers, and Graphene based QHR standards using cryogen free cryocoolers.

Alireza Panna- MSCAlireza Panna was born in Mumbai, India. He received the B.S. degree in Electrical Engineering from the University of Maryland, College Park, MD, USA, in 2013. From 2012 to 2013 he worked as a guest researcher for the National Institutes of Standards and Technology, Gaithersburg, MD, USA, where he was involved in the magnet characterization for the NIST-4 Kibble balance. From 2013 to 2017 he was with the National Institute of Health, Bethesda, MD, USA, where he worked on controls and characterization of various x-ray imaging modalities. Since 2017 he has been with the National Institute of Standards and Technology where he is involved in the Metrology of the Ohm and the Quantum Conductance Projects.


N05 MICROWAVE MEASUREMENT BASICS

1 DAY COURSE: 

MONDAY, NOVEMBER 15th

Presenters: Ron Ginley
For additional technical information, contact Ron Ginley at rginley@ieee.org.

Abstract

Abstract: 

Have you ever wanted to learn more about microwave measurement techniques?  This session is the place to be!  An introduction to the measurement concepts for microwave power and scattering-parameters will be covered. Specific topics covered will include transmission line theory, practical handling or the do’s and don’ts for microwave connectors and connections, Vector Network Analyzer calibration/measurements and real world sources of uncertainties, nonlinear microwave measurements, microwave power detectors types, power measurements and uncertainties, a brief introduction to the NIST Microwave Uncertainty Framework and the session will conclude with a discussion of verification techniques for microwave measurements. There will be a couple of hands-on exercises during the tutorial.

Seminar Developer Biography

Seminar Developer Biography: 

Ron Ginley - MSCRon Ginley is recently retired after being employed by The National Institute of Standards and Technology (NIST) for the past 37 years, all in the microwave area.  At NIST Ron had several areas of responsibility.  He was responsible for the metrology research in the microwave scattering-parameter and power areas and led the microwave measurement services which included the microwave s-parameter, thermal noise and power measurement services.  Ron continues to act as a consultant for NIST.

Ron is an active participant and contributor to the IMS, MSC, NCSL-I and ARFTG conferences.  He has participated in all of these organizations since the mid 1980’s presenting papers and serves on several standards and working committees.  Ron currently is the Treasurer and Executive Committee member of the Automatic Radio Frequency Techniques Group (ARFTG), a professional group dedicated to microwave/mm-wave measurements and is a member of the IEEE Microwave Theory and Techniques Society’s Advisory Committee.  Ron will be chairing the 2022 International Microwave Symposium and has chaired many ARFTG Symposium as well as the 2018 Global Symposium on Millimeter Waves.


N07 – PHOTONICS

1 DAY COURSE: 

MONDAY, NOVEMBER 15th

Presenters: Kevin Douglass
For additional technical information, contact Kevin Douglass at kevin.douglass@nist.gov.

Abstract

Abstract: 

A brief introduction to photonics with applications in sensing will be presented.  Photonic device technology encompasses fiber optics, Fiber Bragg gratings, silicon nano-photonics, opto-mechanics, and more.  The role of photonics is to replace traditional measurement technologies that relay on electrons with technology that uses photons.   The outlook and the opportunities for photonics present in metrology will be discussed.

Seminar Developer Biography

Seminar Developer Biography: 

Kevin Douglass - MSCKevin Douglass is a world class molecular spectroscopist in the Physical Measurement Laboratory at NIST. He is developing rapid and sensitive spectroscopic techniques for the measurement of dynamic pressure.  The goal is to develop the first dynamic pressure standard for the United States based on the fundamentals of spectroscopy. Kevin came to NIST in 2007 and has been developing state-of-the-art spectroscopic tools in areas spanning from the microwave, terahertz, near infrared, and the ultraviolet. His research thus far has resulted in 2 patents with a third pending. Kevin’s current research also extends into the nano-fabricated photonic device technology and leveraging this rapidly evolving technology to develop novel ultra-compact, low cost spectroscopic sensors.


N10 NVLAP

1 DAY COURSE: 

MONDAY, NOVEMBER 15th

Presenters: Kari Harper NIST and Janneth Marcelo

Abstract

Abstract:

This tutorial examines the principles of auditing, the concepts of metrological traceability and tools to apply auditing principles in demonstrating the chain of traceability for measurement results. Auditing concepts such as objective evidence, the internal audit process, and interpersonal skills for auditors will be presented. The auditing module will also incorporate guidance from the newly revised ISO 19011 regarding a risk-based approach to auditing. In the traceability section, emphasis will be placed on the importance of appropriate records for all aspects of the management system and their interdependency with metrological traceability and reporting of results. Using the described auditing principles, both companies with new or mature quality systems will have better success in the auditing process and control of the records necessary to demonstrate the metrological traceability of their measurement results to the International System of Units (SI).

Learning Objectives: At the end of the seminar, using notes and provided resources, participants will be able to:

  1. Define internal audit and metrological traceability
  2. List 4 characteristics of an effective internal auditor
  3. Audit a claim of traceability of a measurement

Seminar Developer Biography

Seminar Developers Biography: 

Kari Harper - MSCKari Harper

  • Program Manager
  • NVLAP
  • 301/975-6612; kharper@nist.gov
  • Shortbio:  Harper joined the Calibration Laboratory Accreditation Program of NVLAP in 2011 after more than two decades as a metrologist in the NIST laboratories.  A mechanical engineer by training, she has worked in the areas of machine tool metrology and vibration metrology.  Ms. Harper participates in standards committees including ASC Z540, ASC S12 Noise, and U.S. TAG to ISO/TC 43/SC1. Ms. Harper is both a lead assessor and technical assessor in NIST’s self-declaration assessment process.  She also served on the Assessment Review Board of NIST’s Quality Management System (2004 to 2011). Ms. Harper served as Acting Quality Manager for the NIST Laboratories (March-June 2018).  Additionally she is a trainee accreditation body peer evaluator for both IAAC and APAC.

(ECT) LAP and managing the Fasteners and Metals LAP. She assists in daily accreditation operations as a staff contact for laboratories in these programs. She also assists in training and monitoring the performance of NVLAP assessors.

Janneth Marcleo - MSCJanneth Marcleo – Ms. Marcelo has over 10 years’ experience in laboratory accreditation and has been with NVLAP for 2 years co-managing the Electromagnetic Compatibility and Telecommunications


COURSES STARTING TUESDAY


N06 REALIZATION AND DISSEMINATION OF MASS IN THE “NEW SI”

1 DAY COURSE: 

TUESDAY, NOVEMBER 16th

Presenters: Eddie Mulhern, NIST
For additional technical information contact Eddie Mulhern at edward.mulhern@nist.gov

Abstract

Abstract: 

This course will provide information on realization and dissemination of mass after the redefinition of the kilogram is adopted in 2019.  Details will be presented on the motivation for redefining the unit of mass and the experiments involved in tying the kilogram to an invariant of nature, the Planck constant.  The effect of the redefinition on uncertainties of the NIST mass scale and customer calibrations will also be presented.

Seminar Developers Biography

Seminar Developers Biography: 

Eddie Mulhern - MSCEdward received a Bachelor of Science in Mechanical Engineering from the University of Maryland in 2014 and a Master of Science in Applied Physics from John’s Hopkins University in 2019. He joined the National Institute of Standards and Technology (NIST) as a guest researcher in 2013 and as a full-time design and automation engineer with the Mass and Force Group in 2014. His current research centers around the mechanical design, testing, and automation of systems in support of the redefinition of the kilogram.

For further information, contact: Eddie Mulhern, Edward.mulhern@nist.gov


COURSES STARTING WEDNESDAY


N08 – GAS PRESSURE MEASUREMENT VIA FIXED LENGTH OPTICAL CAVITY (FLOC) PRESSURE STANDARDS

1 DAY COURSE: 

WEDNESDAY, NOVEMBER 17th

Presenters: Jacob Ricker, NIST, Thermodynamic Metrology Group
For additional technical information contact Jacob Ricker at jacob.ricker@nist.gov

Abstract

Abstract: 

New methods to make primary gas pressure measurements have been developed using refractivity for pressures in the range of 1 Pa to 360 kPa. This range is critical to many applications, including altimetry, weather, and industrial process control, many of which strive for accuracies at the limit of current technical capabilities. Additionally, current primary standards are based on mercury manometers which are being eliminated from use wherever possible. Optical techniques have shown to be equivalent to manometers in accuracy, can be made small and portable, and can be made into primary standards through our understanding of quantum mechanics.

The Fixed Length Optical Cavity (FLOC) pressure standard is already being developed into a commercial product by several manufacturers, however metrologist planning to make use of this portable standard will need to be trained in the basics of FLOC laser cavities and alignment, use and operation of optical refractometers, requirements for making primary measurements, and basics of a FLOC uncertainty estimation. The class will feature hands on demonstrations along with the classroom instruction.

Seminar Developers Biography

Seminar Developers Biography: 

Jacob Ricker - MSCJacob Ricker, works at the National Institute of Standards and Technology where he develops state of the art vacuum calibration systems and conducts research into the next generation vacuum technology.  Jacob maintains and operates the primary standard for pressure and vacuum measurement in the US and is responsible for calibrating pressure and vacuum gauges at NIST in the range of 10-3 Pa to 360 kPa.  His research is focused on new vacuum measurement methods and improving the accuracy of commercial sensors.  Currently, he is the lead designer on new team working to redefine how we measure pressure, temperature, and length.  This team is creating a new primary standard using a revolutionary quantum measurement method.  He has a B.S. from Penn State University in mechanical engineering and a M.S. in applied physics from Johns Hopkins University.  He started at NIST as a student in 2001, however after graduation, he moved on to calibrate underwater acoustics at the Naval Surface Warfare Center before returning to NIST in 2010.

For further information, contact: 
 Jacob Ricker, jacob.ricker@nist.gov


N09 – HUMIDITY

1 DAY COURSE: 

WEDNESDAY, NOVEMBER 17th

Presenters: Christopher Meyer, NIST, Thermodynamic Metrology Group
For additional technical information contact Christopher Meyer at christopher.meyer@nist.gov

Abstract

Abstract: 

Humidity is not a single quantity but a family of quantities that involve moisture content in a gas, including relative humidity, dew point, water amount fraction, and water mass ratio.  This course will teach the fundamentals of these quantities and explain how they relate to each other and are influenced by other quantities, such as temperature and pressure. Applications requiring accurate measurement and/or control of humidity will be discussed. We will also describe the different types of instruments used to measure quantities in the humidity family, including chilled mirror hygrometers (dew point), capacitance sensors (relative humidity), psychrometers (relative humidity), and cavity ringdown spectrometers (water amount fraction). Finally, the course will discuss humidity generators and how they can be used as primary standards for water amount fraction and dew point for calibration of hygrometers. It will show how a humidity generator can be combined with a temperature-controlled chamber to make it a primary standard for calibration of relative humidity sensors. The NIST primary standard humidity generator will be fully described as an example of the type of generators found in National Metrology Institutes.

Seminar Developers Biography

Seminar Developers Biography: 

Christopher Meyer - MSCChristopher Meyer has 30 years of metrology experience working at NIST, working in the areas of temperature, humidity, and pressure standards. He is an honor graduate of Haverford College and received his Ph.D. in physics from the University of California at Santa Barbara. Afterwards, Chris came to NIST as a postdoc, where he and performed acoustic thermometry to obtain some of the most accurate thermodynamic temperature measurements ever made over the range 234 K to 303 K.

He joined the NIST Thermometry Group (Now the Thermodynamic Metrology Group) in 1991. Chris’s first project in this group was to construct a facility to realize the International Temperature Scale of 1990 (ITS-90) over the low-temperature region (0.65 K to 84 K) using 3He and 4He vapor-pressure thermometry, gas thermometry, and platinum resistance thermometry.  Since that time, he has worked in several other areas of thermometry, including wire thermocouples, digital thermometers, light-pipe radiation thermometers, and fluorescence thermometers. Chris has worked in the discipline of humidity since 2000. During this time, he helped develop the current NIST gravimetric hygrometer and the hybrid humidity generator (the US national standard for humidity).  He used the gravimetric hygrometer to validate the performance of hybrid humidity generator and measure thermophysical properties of moist air and moist CO2). Chris has operated the humidity calibration laboratory since 2013. Recently, he spent 15 months working at the International Bureau of Weights and Measures (BIPM), helping develop a manometric system for determination of the amount fraction of CO2 in air. In 2017 Chris entered pressure metrology and he now oversees the NIST piston gauge calibration laboratory.