In a March 13, 2011 media release, issued just two days after the beginning of the Fukushima Daiichi Nuclear Catastrophe in Japan, the U.S. Nuclear Regulatory Commission stated:
"During a nuclear event the NRC has requirements to protect populations around reactors. For instance, the U.S. evacuation standard at 10 miles is roughly equivalent to the 20-kilometer distance recommended in Japan. The United States also uses sheltering in place and potassium iodide, protective measures also available in Japan. United States citizens in Japan are encouraged to follow the protective measures recommended by the Japanese government. These measures appear to be consistent with steps the United States would take."
First, 20 km is 12.4 miles, meaning Japan's evacuation zones are nearly 25% larger than the U.S.'s. Ironically, shortly after NRC's media statement, NRC Chairman Greg Jaczko invoked emergency powers to circumvent resistance by other NRC Commissioners so that he could issue a warning to all Americans in Japan to evacuate at least 50 miles (80.5 km) away from the Fukushima Daiichi nuclear power plant.
Second, regarding sheltering in place, NRC has long been considering shrinking American evacuation zones to 2 miles, and instructing persons living within 2 to 8 miles of a nuclear accident to merely "shelter in place." In Japan, the initial evacuation orders applied only to a 3 km (about 2 mi) radius, which within hours had to be expanded to 20 km (12.4 mi). In certain directions such as to the northwest, where wind and precipitation made Fukushima fallout severe, the evacuation zone had to be dramatically expanded. Many critics warn that the 12.4 mile evacuation radius around Fukushima Daiichi is dangerously small.
Third, NRC has dragged its heels on enforcing a federal law requiring pre-deployed potassium iodide distribution out to 20 miles downwind of U.S. reactors in order to prepare for radioactivity releases ahead of time. NRC simply refuses to carry out the legal mandate. But then again, NRC resisted previous efforts to require potassium iodide pre-deployment. An NRC staffer named Peter Crane, himself a survivor of thyroid cancer, endeavored for many years on end to officially petition the NRC to take this basic health-protection action.
Finally, it was ironic for the NRC to instruct Americans in Japan to follow Japanese government instructions. As mentioned above, NRC Chairman Jaczko quickly saw the need to warn Americans to evacuate 50 miles away, not just 12.4 miles away as the Japanese government said.