Four Sites Where You Can Monitor U.S. Radiation Levels

I've updated this post at top with current sites, as of March 2015, but below that I've left intact the historical post, which I first published during the Fukushima nuclear disaster, and then updated in 2013.
The U.S. government's sites have changed most dramatically since the Fukushima meltdowns. It's no longer as easy to access federal radiation data as it was when the government was publishing lab results to an open-data system in the Spring of 2011. Nonetheless, EPA's Radnet system remains the most extensive and reliable radiation monitoring system in the U.S. that the public can access.
You can monitor EPA's Radnet stations just like the EPA scientists do by keeping your eye on these graphs that display RadNet's continuous air monitoring results in "near real time." They are updated several times daily.
To access the graphs, click on a station on the map. For a list of local monitors, scroll down and click on the name of a state.
Current and historical gross data are available in EPA's Central Data Exchange, which is unavailable as I write this, and which is designed for scientists anyway, as you'll see should you succeed in accessing it and then try to use it. Fortunately, EPA offers another database that's slightly less user hostile, Envirofacts….
In addition to transmitting data on gross alpha and gross beta radiation to EPA headquarters, the Radnet stations have filters that sample air particulates and collection stations for rainwater. EPA also monitors radiation in drinking water, and it used to monitor surface water (discontinued in 1999) and pasteurized milk (discontinued in 2014).
Envirofacts is a clunky, persnickety, difficult database tool allows you to access EPA lab results by location, gross results or specific radionuclide, and by media: air particulates, precipitation, drinking water, surface water or pasteurized milk.
There's a user guide you'll want to consult unless you're already an expert at using Envirofacts.
There's also a highly focused regional monitoring system in the United States, the Nevada Program…
If there’s a benefit to having 928 nuclear explosions in your state, it might be having the nation’s greatest concentration of radiation monitoring stations.
A legacy of the Nevada Proving Grounds, Nevada’s radiation monitoring program was reinvigorated after Sept. 11. Operated by the Department of Energy and the Desert Research Institute, the Community Environmental Monitoring Program only covers Nevada and Utah, but it should be of interest to states downwind.
Click on a station for historical results. Click “most recent results” for more detail. While you’re at it you can learn air temperature, soil temperature, barometric pressure, wind speed, wind direction, and more.
The government depends on volunteers—many of them high-school science teachers—to visit its radiation monitoring stations, collect air filters, and bring them in for testing. Thanks to them, Nevadans can keep close watch—with some delay—on radiation levels in the air they breathe.
Don’t trust the government? Mineralab, a Prescott, Arizona, company that sells geiger counters, maintains the Radiation Network…
Mineralab describes radiationnetwork.com as “a nationwide grass roots effort to monitor the radiation in our environment.”
The network collects data from private citizens nationwide who keep their geiger-counters running, with data uploading automatically to the website in real time. The site recently added citizen monitors in Europe and Japan.
The Radiation Network’s map also displays potential sources of radiation across the U.S., including nuclear power plants, testing sites, waste collection facilities, etc.
(Some readers also have recommended the Nuclear Emergency Tracking Center, which mingles data from private radiation monitoring stations and the EPA network and charges for historical data, some of which may be available free elsewhere.)
Below, the original post…
UPDATED with a fourth site, EPA's RadNet Lab Open Data system.
Radiation from Japan's Fukushima nuclear disaster has been detected in the air in five Western states and in rainwater in at least two so far.
While federal officials continue to assure the public that no harmful levels have reached the United States, some Americans have not been content to take the government at its word. Geiger counters have been selling like popsicles in summer, and traffic has never been higher at websites that display data from radiation monitoring stations.
We list three such sites below.
Officials have said Fukushima radiation cannot reach the U.S. without being diluted to safe levels, and that the isotopes detected so far would not be sufficient to bump the numbers recorded on these sites, but should you wish to keep your own eye on things:
2013 Update: Both of the links in this section are now out of date. EPA's Radnet data is now available through this page.
2011 Update: Since the post was originally published, the Environmental Protection Agency launched a new open-data system where it posts laboratory results from its sampling of air, precipitation, drinking water and milk. The new system can be found here: RadNet Sampling Data.
The Environmental Protection Agency's RadNet system is designed to detect radiation from accidents like the Fukushima disaster in Japan and from foreign nuclear tests. It displays a map of the United States with monitoring stations highlighted. Click on one for a graphic representation of its data.
Last night the graphs were displaying no data—in the wake of EPA's revelation that radiation had been detected in rainwater. Above empty frames appeared the message, in bold: "To-date, levels recorded at this monitor have been thousands of times below any conservative level of concern."
But when the system is working, it collects data from more than 140 monitoring stations that sniff the air at three times the rate of normal human breathing. The stations collect particles on filters, analyze their radioactivity and transmit data hourly to EPA, where officials review the numbers and post the graphs online within two hours.
RadNet also issues a daily report, which almost always says, "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."
If there's a benefit to having 928 nuclear explosions in your state, it might be having the nation's greatest concentration of radiation monitoring stations.
A legacy of the Nevada Proving Grounds, Nevada's radiation monitoring program was reinvigorated after Sept. 11. Operated by the Department of Energy and the Desert Research Institute, the Community Environmental Monitoring Program only covers Nevada and Utah, but it should be of interest to states downwind.
Click on a station for historical results. Click "most recent results" for more detail. While you're at it you can learn air temperature, soil temperature, barometric pressure, wind speed, wind direction, and more.
The government depends on volunteers—many of them high-school science teachers—to visit its radiation monitoring stations, collect air filters, and bring them in for testing. Thanks to them, Nevadans can keep close watch—with some delay—on radiation levels in the air they breathe.
Unlike the EPA's system, the CEMP was working last night, reporting detailed readings at levels presumed to be safe.
Radiation Network
Don't trust the government? Mineralab, a Prescott, Arizona, company that sells geiger counters, maintains radiationnetwork.com, "a nationwide grass roots effort to monitor the radiation in our environment."
The network collects data from private citizens nationwide who keep their geiger-counters running, with data uploading automatically to the website in real time. The site recently added citizen monitors in Europe and Japan.
The Radiation Network's map also displays potential sources of radiation across the U.S., including nuclear power plants, testing sites, waste collection facilities, etc.
"Our Monitoring Stations have not yet registered a big, or even perceptibly significant 'Gamma event' from any radiation drifting over from Japan, so we can take a little solace in that," said Tim Flanegin, who operates the site.
"You know, there is an interesting paradox in the field of radiation monitoring. On the one hand, we might use a Geiger counter to perform a radiation scan of a suspected object or situation, and in a weird sort of way, we want a "hit" to confirm our fears, but on the other hand, if we don't get a detection, some of us are understandably a little disappointed. But in that case, of course, we should instead breathe a sigh of relief.

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