EPA’s RadNet system continuously monitors radiation levels in the air throughout the U.S., 24 hours a day, 7 days a week. RadNet sample analyses and monitoring results of precipitation, drinking water, and milk provide baseline data on background levels of radiation in the environment and can detect increased radiation from radiological incidents. RadNet has not found any radioactive elements associated with the damaged Japanese reactors since late 2011, and even then, the levels found were very low—always well below any level of public health concern. You can see near real-time air monitoring results and download sample analysis results on the RadNet website.
We work with other federal agencies, including the National Oceanic and Atmospheric Administration (NOAA), the Food and Drug Administration (FDA), and the Nuclear Regulatory Commission (NRC) to carefully follow the situation at Fukushima.