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CCQM-P151 Draft A Report Pilot Study CCQM P151 Halocarbons in Dry Whole Air



George C. Rhoderick, Franklin R. Guenther, David L. Duewer, Jeongsoon Lee, Jin S. Kim, Bradley Hall, Ray Weiss, Christina Harth, Stefan Reimann, Martin Vollmer


The growing awareness of climate change/global warming and continuing concerns regarding stratospheric ozone depletion will require future measurements and standards for many compounds, in particular halocarbons that are linked to these issues. In order to track and possibly control the emissions of these species globally in the atmosphere, it is necessary to demonstrate measurement equivalence at the highest levels of accuracy for assigned values of standards. This report describes the results of a pilot study between National Metrology Institutes and atmospheric research labortories for several of the more important halocarbons at atmospheric concentration levels. The comparison includes the chlorofluorocarbons (CFCs) dichlorodifluoromethane (CFC 12), trichlorofluoromethane (CFC 11), and 1,1,2 trichlorotrifluoroethane (CFC 113); the hydrogen chlorofluorocarbons (HCFCs) difluorochloromethane (HCFC 22) and difluorochloroethane (HCFC 142b); and the hydrogen fluorocarbon (HFC) 1,1,1,2 tetrafluoroethane (HFC 134a), all in a dried whole air sample. The objective of this key comparison is to compare the measurement capabilities of the participants for these halocarbons at trace atmospheric levels.


Rhoderick, G. , Guenther, F. , Duewer, D. , Lee, J. , Kim, J. , Hall, B. , Weiss, R. , Harth, C. , Reimann, S. and Vollmer, M. (2014), CCQM-P151 Draft A Report Pilot Study CCQM P151 Halocarbons in Dry Whole Air, Metrologia, [online], (Accessed April 22, 2024)
Created May 27, 2014, Updated September 25, 2020