Nuclear plant workers unsure of internal exposure levels

Nearly two months after the start of the crisis at the Fukushima No. 1 nuclear power plant, only 10 per cent of workers there had been tested for internal radiation exposure caused by inhalation or ingestion of radioactive substances, due to a shortage of testing equipment available for them. -- PHOTO: AP

NEARLY two months after the start of the crisis at the Fukushima No. 1 nuclear power plant, only 10 per cent of workers there had been tested for internal radiation exposure caused by inhalation or ingestion of radioactive substances, due to a shortage of testing equipment available for them.

Tokyo Electric Power Co. (Tepco), operator of the crippled nuclear compound, is finding it impossible to use testing apparatus set up inside the facility because of high radiation levels recorded near the equipment.

A number of personnel working to overcome the nuclear crisis at the facility are increasingly alarmed by their lack of internal exposure testing. Some have said they may have to continue to work at the facility without knowing whether their radiation exposure levels have exceeded the upper limit set by the government.

On Tuesday, the government revealed a timetable for ending the nuclear crisis. The road map called for increased surveillance of the workers' radiation levels, including a measure requiring Tepco to periodically report such data to the government.

Internal exposure is caused by taking radioactive substances into the body via eating, drinking or breathing. Its unit, counts per minute (cpm), indicates the amount of radiation emitted per minute.

Regulations on preventing health problems caused by ionizing radiation require operators of power plants to conduct internal exposure tests every three months on plant employees who enter areas designated by laws and regulations on radiation-related health problems. -- THE YOMIURI SHIMBUN/ANN