Monitoring dosimeter compliance at nuclear plant anything but easy

August 14, 2012


It sounds good on paper. But confirming whether nuclear power plant workers are carrying dosimeters is harder than it might seem.

Even before Tokyo Electric Power Co.'s Aug. 13 announcement of stricter monitoring of dosimeter use by plant workers, some of those very workers were saying how difficult it would be to implement.

In one instance on Aug. 8, a man in his 40s was stopped on his way to a work site at the crippled Fukushima No. 1 nuclear power plant.

The man was summoned to the quake-resistant control center and told that someone would check whether he had a dosimeter.

The person doing the check worked for a nuclear plant maintenance company that had been given the task by TEPCO of monitoring radiation exposure among workers.

The individual squeezed a part of the worker's white protective gear above the left side of his chest. Workers usually place dosimeters in the left chest pocket of the shirts they wear under the protective gear.

Because the protective suits are so bulky, the individual had difficulty confirming the presence of the dosimeter even though the worker had it in his left chest pocket. The individual squeezed the right chest area of the protective gear where the worker kept his mobile phone. The inspector felt the mobile phone, assumed it was the dosimeter, and waved the man through.

TEPCO implemented body checks of all workers before they head to a site as part of measures to prevent a recurrence of attempts to conceal radiation doses to which workers at the plant were exposed.

The worker in his 40s said: "Just by feeling from outside of the protective gear, it is difficult to distinguish between a dosimeter and a mobile phone. Even if such efforts could lead to confirmation of dosimeter use, it would only prevent workers who innocently forgot to wear the dosimeter. There would be no way of finding those individuals who did it on purpose."

In late July, The Asahi Shimbun was the first to report that subcontracted workers, at the behest of their boss, used lead plates to cover the dosimeters to keep radiation dose readings at lower levels. A number of other tricks were later unveiled, such as leaving dosimeters in cars parked within plant grounds.

Once the workers got past the inspection at the main gate to the plant, there was no way to tell whether they were complying with the company's regulations.

Doubts about TEPCO's new monitoring measures were also being raised by those who work for the company handling plant maintenance.

A man in his 50s who was conducting body checks of workers told a colleague, "I cannot tell the difference between a dosimeter, a pack of cigarettes or a mobile phone."

While handing dosimeters to each individual worker would ensure that everyone had one, TEPCO continues to allow leaders of work groups to pick up all the dosimeters for the other members of the team.

That allows most workers to go directly to a work site without checking in at the quake-resistant control center.

As small groups of workers often work together, monitors will be unable to uncover irregularities if all members of each team gave the same story.

Many subcontracted workers concealed their radiation doses due to concern about their job security. High readings translate into no work.

Employees of TEPCO or other major companies who exceed the annual radiation dosage limit can be assigned to work tasks away from the nuclear plant, but there is no such alternative for workers at subcontractors who are usually on short-term contracts. If they exceed the radiation dosage limit, they face losing their jobs.

While the labor ministry and the Nuclear and Industrial Safety Agency have asked TEPCO to be more vigilant about strengthening monitoring of dosimeter use, nothing has been done about ensuring greater job security.

Unless steps are taken, workers will continue to conceal their radiation dosage levels to protect their livelihood.

(This article was compiled from reports by Miki Aoki, Tamiyuki Kihara and Toshio Tada.)

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Nuclear plant workers receive dosimeters before heading to the Fukushima No. 1 nuclear power plant. (Provided by TEPCO)

Nuclear plant workers receive dosimeters before heading to the Fukushima No. 1 nuclear power plant. (Provided by TEPCO)

  • Nuclear plant workers receive dosimeters before heading to the Fukushima No. 1 nuclear power plant. (Provided by TEPCO)

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