WASHINGTON (Reuters) - The U.S. military took new steps to shield personnel from radiation spread by Japan’s crippled nuclear plant on Tuesday, redirecting arriving warships to safer waters and telling some forces to limit time outdoors.
But the U.S. Navy said it would not stop flying relief missions to help Japan after its devastating earthquake and tsunami, even as more U.S. flight crews were exposed to low-level - but higher than normal - radiation.
Two U.S. naval bases in Japan also detected elevated levels of airborne radiation.
“This is not going to sway us from the mission,” said Lieutenant Anthony Falvo at the U.S. Navy’s Seventh Fleet.
“All of our crews that are out there are going to be exposed to some level of radiation. These are very low, manageable levels.”
A day after saying 17 Americans on helicopter missions had been exposed to a month’s worth of normal radiation, the Navy acknowledged several more air crews had been similarly affected.
“For those that are returning with detectable levels of radiation, we are taking all measures to ensure they are fully decontaminated,” Falvo said.
New explosions on Tuesday at the Fukushima plant, 180 miles north of Tokyo, released low levels of radiation, worsening Japan’s nuclear crisis.
At the Yokosuka Naval Base, 200 miles south of the plant, the U.S. Navy recommended personnel and families to take precautions after detecting low levels of radiation there. The same instructions were given to personnel at Naval Air Facility Atsugi, which is about 150 miles from the plant.
The precautions included limiting outdoor activity but also shutting external ventilation systems “as much as practical.”
Rear Admiral Richard Wren, commander of U.S. Naval Forces Japan, said the additional radiation exposure for the past 12 hours at the two bases was about 20 millirem, less than one month’s exposure to naturally occurring background radiation.
“There is no appreciable health risk, and we are being very conservative in our recommendations,” Wren said in a video message to naval forces.
The U.S. Navy also said some arriving warships will be stationed off the west coast of Honshu, Japan’s largest island, instead of heading to the east coast as planned because of “radiological and navigation hazards.”
The ships are the USS Essex, a large amphibious assault ship; USS Harpers Ferry, a dock-landing ship; and USS Germantown, an amphibious dock-landing ship, the Navy said.
The Navy earlier repositioned eight other warships, including the aircraft carrier USS Ronald Reagan, after they were caught 115 miles downwind of the nuclear plant.
The Ronald Reagan Carrier Strike Group on Tuesday delivered 17 tons of supplies including food, water and blankets. U.S. aircraft also conducted various coastal search and rescue missions.