EPA - Japanese Nuclear Emergency: Radiation Monitoring

[OKIsItJustMe]

http://www.epa.gov/japan2011/data-updates.html

Daily Data Summary

Last updated on 03/22/2011 at 19:36:45.

As the Nuclear Regulatory Commission has said, we do not expect to see radiation at harmful levels reaching the U.S. from damaged Japanese nuclear power plants. As part of the federal government's continuing effort to make our activities and science transparent and available to the public, the Environmental Protection Agency (EPA) will continue to keep all RadNet data available in the current online database. EPA is working with its federal partners and has deployed additional monitors to Hawaii, Alaska, Guam and the Northern Mariana Islands.

EPA is utilizing this existing nationwide radiation monitoring system, RadNet, which continuously monitors the nation's air and regularly monitors drinking water, milk and precipitation for environmental radiation. The RadNet online searchable database contains historical data of environmental radiation monitoring data from all fifty states and U.S. territories.

EPA will provide daily data summaries of our radiation air monitoring efforts. We will continue to keep all RadNet data available in the current http://epa.gov/cdx/">online database.

March 22, 2011

As of 6:30pm (EDT) preliminary monitor results in Hawaii detected minuscule levels of an isotope that is consistent with the Japanese nuclear incident. This detection varies from background and historical data in Hawaii. This isotope was detected at our fixed monitor in Hawaii, and it is far below any level of concern for human health. The sampling filter from this monitor is being sent to our national radiation lab for further analysis.

EPA's RadNet radiation air monitors across the rest of the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

March 21, 2011

As of 1:00pm (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

As of 9:00am (EDT) EPA's RadNet radiation air monitors across the U.S. show typical fluctuations in background radiation levels. The levels detected are far below levels of concern.

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Check the Honolulu readings here:
http://www.epa.gov/japan2011/rert/radnet-honolulu-bg.html

[flamingdem]

1. The monitoring station in Hawaii is still off line nt

[OKIsItJustMe]

2. Not exactly. Gamma counts are still available (Beta counts are off-line.)

http://www.epa.gov/japan2011/rert/radnet-honolulu-bg.html
“Gross beta counts are temporarily unavailable due to mechanical issues. See gamma counts below.”



http://en.wikipedia.org/wiki/Gamma_ray#Health_effects

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All ionizing radiation causes similar damage at a cellular level, but because rays of alpha particles and beta particles are relatively non-penetrating, external exposure to them causes only localized damage, e.g. radiation burns to the skin. Gamma rays and neutrons are more penetrating, causing diffuse damage throughout the body (e.g. radiation sickness), increasing incidence of cancer rather than burns. External radiation exposure should also be distinguished from internal exposure, due to ingested or inhaled radioactive substances, which, depending on the substance's chemical nature, can produce both diffuse and localized internal damage. The most biological damaging forms of gamma radiation occur in the gamma ray window, between 3 and 10 MeV, with higher energy gamma rays being less harmful because the body is relatively transparent to them. See cobalt-60.

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http://en.wikipedia.org/wiki/Beta_particle#Health

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Beta particles are able to penetrate living matter to a certain extent and can change the structure of struck molecules. In most cases such change can be considered as damage with results possibly as severe as cancer and death. If the struck molecule is DNA it can show a spontaneous mutation.

Beta sources can be used in radiation therapy to kill cancer cells.

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