Since the five-year radiation limit for Fukushima No. 1 workers is 100 millisieverts per person, many could be barred from working at the plant.
The yearly limit for decontamination workers stands at 50 millisieverts, according to the Health, Labor and Welfare Ministry.
Of those who topped the 20-millisievert level in 2014, only 11 are from Tepco, with 981 from subcontractors. The highest doses logged were 29.5 millisieverts among Tepco’s staff and 39.85 millisieverts among the subcontractors.
The data also showed that 20,695 plant workers were exposed in fiscal 2014, with doses averaging 4.99 millisieverts. That’s higher than the 14,746 exposed in the previous year, but lower in terms of dosage, which averaged 5.25 millisieverts in 2013.
The jump in exposures was partly attributable to an overall increase in workers at the plant since the previous year.
A public relations official at Tokyo Electric Power Co., which runs the meltdown-hit plant, said the amount of decontamination and debris-removal work in high-radiation zones there is also rising.