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Models for an Ultraviolet-C Research and Development Consortium
No full textThe development of an international, precompetitive, collaborative, ultraviolet (UV) research consortium is discussed as an opportunity to lay the groundwork for a new UV commercial industry and the supply chain to support this industry. History has demonstrated that consortia can offer promising approaches to solve many common, current industry challenges, such as the paucity of data regarding the doses of ultraviolet-C (UV-C, 200 nm to 280 nm) radiation necessary to achieve the desired reductions in healthcare pathogens and the ability of mobile disinfection devices to deliver adequate doses to the different types of surfaces in a whole-room environment. Standard methods for testing are only in the initial stages of development, making it difficult to choose a specific UV-C device for a healthcare application. Currently, the public interest in UV-C disinfection applications is elevated due to the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes the respiratory coronavirus disease 19 (COVID-19). By channeling the expertise of different UV industry stakeholder sectors into a unified international consortium, innovation in UV measurements and data could be developed to support test methods and standards development for UV healthcare equipment. As discussed in this paper, several successful examples of consortia are applicable to the UV industry to help solve these types of common problems. It is anticipated that a consortium for the industry could lead to UV applications for disinfection becoming globally prolific and commonplace in residential, work, business, and school settings as well as in transportation (bus, rail, air, ship) environments. Aggressive elimination of infectious agents by UV-C technologies would also help to reduce the evolution of antibiotic-resistant bacteria
In Situ Thermography During Laser Powder Bed Fusion of a Nickel Superalloy 625 Artifact with Various Overhangs and Supports
No full text
Broadband Dielectric Spectroscopy as a Potential Label-Free Method to Rapidly Verify Ultraviolet-C Radiation Disinfection
No full textMicrowave (MW) sensing offers noninvasive, real-time detection of the electromagnetic properties of biological materials via the highly concentrated electromagnetic fields, for which advantages include wide bandwidth, small size, and cost-effective fabrication. In this paper, we present the application of MW broadband dielectric spectroscopy (BDS) coupled to a fabricated biological thin film for evaluating ultraviolet-C (UV-C) exposure effects. The BDS thin film technique could be deployed as a biological indicator for assessing whole-room UV-C surface disinfection. The disinfection process is monitored by BDS as changes in the electrical properties of surface-confined biological thin films photodegraded with UV-C radiation. Fetal bovine serum (FBS, a surrogate for protein) and bacteriophage lambda double-stranded deoxyribonucleic acid (dsDNA) were continuously monitored with BDS during UV-C radiation exposure. The electrical resistance of FBS films yielded promising yet imprecise readings, whereas the resistance of dsDNA films discernibly decreased with UV-C exposure. The observations are consistent with the expected photo-oxidation and photodecomposition of protein and DNA. While further research is needed to characterize these measurements, this study presents the first application of BDS to evaluate the electrical properties of solid-state biological thin films. This technique shows promise toward the development of a test method and a standard biological test to determine the efficacy of UV-C disinfection. Such a test with biological indicators could easily be applied to hospital rooms between patient occupancy for a multipoint evaluation to determine if a room meets a disinfection threshold set for new patients
Estimation of the Ultraviolet-C Doses from Mercury Lamps and Light-Emitting Diodes Required to Disinfect Surfaces
No full textDisinfection of surfaces by ultraviolet-C (UV-C) radiation is gaining importance in diverse applications. However, there is generally no accepted computational procedure to determine the minimum irradiation times and UV-C doses required for reliable and secure disinfection of surfaces. UV-C dose distributions must be comparable for devices presently on the market and future ones, as well as for the diverse surfaces of objects to be disinfected. A mathematical model is presented to estimate irradiance distributions. To this end, the relevant parameters are defined. These parameters are the optical properties of the UV-C light sources, such as wavelength and emitted optical power, as well as electrical features, like radiant efficiency and consumed power. Furthermore, the characteristics and geometry of the irradiated surfaces as well as the positions of the irradiated surfaces in relation to the UV-C light sources are considered. Because mercury (Hg) lamps are competitive with UV-C light-emitting diodes, a comparative analysis between these two light sources based on the simulation results is also discussed
Efficacy of Ultraviolet-C Devices for the Disinfection of Personal Protective Equipment Fabrics and N95 Respirators
No full textSince the onset of the coronavirus disease 2019 (COVID-19) pandemic, a plethora of ultraviolet-C (UV-C) disinfection products have come to market, especially in emerging economies. UV-C�based disinfection products for mobile phones, food packaging, face masks and personal protective equipment (PPE), and other everyday objects are available in popular electronic-commerce platforms as consumer products. Product designers from multinational to startup companies began to design UV-C disinfection products but had no prior-art reference, user feedback, or validation of product efficacy, which are important stages in product design. A UV-C disinfection product cannot be assessed by most consumers for its viricidal efficacy. Many firms entered the domain of UV-C products and were unaware of the necessary validation requirements. Lack of availability and access to virology laboratories, due to lockdowns in countries, and lack of standards and certification for UV-C disinfection products limited product designers and firms in benchmarking their UV-C�based devices before market release. This work evaluates two UV-C disinfection devices for viricidal efficacy on PPE fabric and National Institute for Occupational Safety and Health (NIOSH)�certified N95 respirators through controlled experiments using the H1N1 virus, which is enveloped and is transmitted via the respiratory route similar to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of COVID-19. The experiment also evaluated the effectiveness of chemical disinfectants along with and versus UV-C disinfection. Experiments for material selection, UV dose calculation, and UV endurance of PPE samples to be disinfected are also discussed. The outcome of this work establishes a systematic method to validate the efficacy of UV-C disinfection products. The design guidelines would benefit product designers in designing UV-C�based disinfection products
ERNEST L. GARNER
No full textNBS/NIST: 1958–2000
INDUCTED: 2021
B: 1934, Garysburg, North Carolina
EDUCATION:
Virginia State University, BS (Physics), 1956
U.S. Army Ordnance Corps Officer, 1956-1958
CITATION:
For leadership in isotope ratio measurements of reference materials critical to the international nuclear safeguards effort and for contributions to the establishment of international quality standards for calibration and measurement laboratories
POSITIONS HELD AT NBS/NIST:
Physicist, Analytical Mass Spectrometry Section, Analytical Chemistry Division, Institute for Materials Research, 1958-1974
Staff, Nuclear Safeguards Measurements Program, Institute for Basic Standards, 1975-1977
Chief, Inorganic Analytical Research Division, Center for Analytical Chemistry, National Measurement Laboratory (NML), 1978-1984
Chief, Office of Physical Measurement Services, NML, 1985-1987
Department of Commerce Science Fellow, Office of the Under Secretary for Defense, Research and Development, 1988-1989
Deputy Chief, Calibration Program, Technology Services, 1989-2000
HONORS:
U.S. Department of Commerce Silver Medal (1971)
National Conference of Standards Laboratories International, William Wildhack Award (2000)
Government-Industry Data Exchange Program, Metrology Appreciation Award (2000)
MEMBERSHIPS:
American Society for Mass Spectrometry
American Association for the Advancement of Science
National Conference of Standards Laboratories International
PUBLICATIONS:
More than 40 publications including:
Rosholt, J.N., Shields, W.R., and Garner, E.L., “Isotopic Fractionation of Uranium in Sandstone”, Science, 139 (355), 224-226 (1963)
Catanzaro, E.J., Murphy, T.J., Shields, W.R., and Garner. E.L., “Absolute Isotopic Abundance Ratios of Common Equal-Atom and Radiogenic Lead Isotopic Standards”, J. of Res. of NBS Section A-Physics and Chemistry, A72 (3), 261-267 (1968)
Catanzaro, E.J., Champion, C.E., Garner, E.L., Marinenko, G., Sappenfield, K.M., and Shields, W.R., Standard Reference Materials: Boric Acid; Isotopic and Assay, Standard Reference Materials, NIST SP 260-17 (1970)
Garner, E.L., Machlan, L.A., and Shields, W.R., Standard Reference Materials: Uranium Isotopic Standard Reference Materials Certification of Uranium Isotopic Standard Reference Materials, NIST SP 260-27 (1971)
Garner, E.L., Machlan, L.A., and Barnes, I.L., “The Isotopic Composition of Lithium, Potassium, and Rubidium in Some Apollo 11, 12, 14, 15, and 16 Samples”, Proc. Lunar Sci. Conf. 6th, 1845-1855 (1975)
Velapoldi, R.A., Paule, R.C., Schaffer, R., Mandel, J., Machlan, L.A., Garner, E.L., and Rains, T.C., Standard Reference Materials: A Reference Method for the Determination of Lithium in Serum, NIST SP 260-69 (1980
RICHARD R. CAVANAGH
No full textNBS/NIST: 1979–2019
INDUCTED: 2021
B: 1950, Detroit, Michigan
EDUCATION:
Wayne State University, BA (Chemistry), 1972
Harvard University, MS (Chemistry), 1974
Harvard University, PhD (Physical Chemistry), 1978
CITATION: For outstanding scientific contributions to time-resolved studies of molecular dynamics on surfaces and leadership of a broad range of NIST technical programs
POSITIONS HELD AT NBS/NIST:
NAS/NRC Postdoctoral Research Associate, Surface Science Division, National Measurement Laboratory (NML), 1979-1980
Research Chemist, Surface Science Division, NML, 1980-1988
Group Leader, Surface Dynamical Processes Group, Surface Science Division, NML, and then Surface and Microanalysis Science Division, Chemical Science and Technology Laboratory (CSTL), 1988-1998
Chief, Surface and Microanalysis Science Division, CSTL, 1999-2008
Deputy Director, CSTL and then Materials Measurement Laboratory (MML), 2008-2012
Chair, NIST Institutional Review Board, 2009-2014
Acting Director, MML, 2011-2012
Director, Special Programs Office, 2012-2019
Acting Associate Director for Laboratory Programs, 2014-2016
HONORS:
U.S. Department of Commerce Silver Medal (1984)
U.S. Department of Commerce Gold Medal (1990)
Samuel Wesley Stratton Award (1992)
Fellow, American Vacuum Society (2003)
Fellow, American Physical Society (2004)
Presidential Rank Award (2017)
MEMBERSHIPS:
American Vacuum Society
American Physical Society
PUBLICATIONS:
More than 100 publications including:
Cavanagh, R.R. and Yates, Jr., J.T., “Site Distribution Studies of Rh Supported on Al203: An Infrared Study of Chemisorbed CO”, J. Chem. Phys., 74, 4150-4155 (1981)
Rush, J.J., Cavanagh, R.R., Kelley, R.D., and Rowe, J.M., “Interaction of Vibrating H Atoms on the Surface of Platinum Particles by Isotope Dilution Neutron Spectroscopy”. J. Chem. Phys., 83, 5339-5341 (1985)
Cavanagh, R.R., Beckerle, J.D., Casassa, M.P., Heilweil, E.J. and Stephenson, J.C., “Subpicosecond Probing of Vibrational Energy Transfer at Surfaces”, Surface Science, 269/270, 113-119 (1992)
Cavanagh, R.R., King, D.S., Stephenson, J.C., and Heinz T.F., “Dynamics of Nonthermal Reactions: Femtosecond Surface Chemistry”, J. Phys. Chem., 97, 786-798 (1993)
Cavanagh, R.R., Heilweil, E.J., and Stephenson, J.C., “Time-Resolved Measurements of Energy Transfer at Surfaces”, Surface Science, 299/300, 643-655 (1994
(Audio) NIST Oral History Interview about the Boulder Microfabrication (Cleanroom) Facility - June 24, 2021
No full textCurrent and former NIST employees gathered on June 24, 2021, to share an oral history interview about NIST's Microfabrication (Cleanroom) in Boulder, Colorado. Those recorded for this oral history included Jim Beall, Richard (Dick) Harris, Don McDonald, Richard (Dick) Kautz, Clark Hamilton, Robert (Bob) Phelan, Jr., Dave Redmund. Rebecca Jacobson of the NIST Boulder Public Affairs Office faclitated the interview
Oral History of Judah Levine - June 29, 2021
No full textJudah Levine discusses his involvement in the Poor Man mine located west of Boulder, CO. Dr. Levine joined the NBS-University of Colorado Joint Institute of Laboratory Astrophysics (JILA) as a postdoc in 1967, and then was hired at the National Bureau of Standards (NBS) in 1969. He is currently a Fellow at NIST and is the leader of the Network Synchronization Project in the Time and Frequency Division. He describes the laser interferometer that was built in a shaft of the Poor Man mine and explains its history and its use as an early earth-level strain meter. He further discusses his involvement with the geophysical community resulting from his early work in the mine. The interview was conducted by William Kirchhoff and John Lowe