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ARL News

Survey of New York City planned

For atmospheric dispersion studies, the atmospheric tracer of choice is often sulfur hexafluoride (SF6). It is planned that there will be some releases of SF6 in the coming multi-agency field studies of dispersion in New York City, now being planned. However, SF6 is an insulating gas commonly used in electrical substations. These substations leak considerable quantities of SF6 into the atmosphere, at rates often well above those normally used for atmospheric tracer studies. Two important considerations then arise. First, how can field experiments be designed to avoid the interferance from these industrial sources? Second, can the releases from substations be used to help improve understanding of the processes that control dispersion in urban areas and in cities? Both questions are being explored by the ARL team from Idaho Falls.

A survey of SF6 levels in New York City is now being planned, as a joint program of DHS, DTRA and ARL. The studies will likely take place in July, in advance of the major field effort now planned for August.

Contact information: Bruce B. Hicks
Phone: (301) 713-0684
e-mail: bruce.hicks@noaa.gov