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2018 Bronze Medal Award

Nelson, Lippa, Toman

Nelson, Lippa, Toman


Lippa, Nelson, and Toman are recognized for the development of rigorous analytical methods and data-evaluation processes for the determination of chemical purity, and for transfer of this technology to the private sector for the development of a new class of primary Standard Reference Materials. Knowledge of chemical purity is essential for accurate amount-of-substance measurements and for establishing the metrological traceability of these results to the International System of Units (SI). The team’s processes are applicable to a range of NIST’s measurement services, with applications that extend from healthcare delivery to forensic purity assessment of seized drugs. 


Katrice Lippa

Supervisory Research Chemist
Material Measurement Laboratory

Michael Nelson

Research Chemist
Material Measurement Laboratory

Blaza Toman

Mathematical Statistician
Information Technology Laboratory