Tokyo Electric Power Co. (TEPCO) is preparing to bring in foreign workers with special technical skills to join decommissioning work on the disaster-stricken Fukushima Daiichi nuclear plant.

At present, an average of 4,000 employees of TEPCO and cooperating firms work at the facility every day. Laws and regulations stipulate that workers' radiation exposure must be limited to 50 millisieverts in a single year, and 100 millisieverts over five years. No one is allowed to stay at the plant once they hit one of these caps, so waves of new employees must be brought in to maintain worker numbers.

Decommissioning the Daiichi plant, which suffered a triple core meltdown in the wake of the March 2011 Great East Japan Earthquake and tsunami, is expected to take 30 to 40 years. Whether the companies involved can sustain sufficient staffing levels will be one factor that determines the success or failure of the project.

When it comes to tapping foreign labor to make up the required numbers, the Justice Ministry -- which has jurisdiction over Japan's immigration system -- has already declined to approve sending foreign technical intern trainees to work at the plant. One of the core tenets of the foreign technical trainee program is that the job placements must provide the trainees with skills they can use in their home countries, and working to decommission a devastated nuclear plant did not fit the bill.

TEPCO is now turning its eyes to foreign workers with Category 1 work visas, one of the new residency statuses launched on April 1 and aimed at those with certain skills and experience. Technical trainees with three years' experience in Japan can obtain this visa without a skills exam.

However, there is a real risk of radiation exposure at the Daiichi plant, and the terminology used on-site is highly technical, making for a difficult environment. TEPCO and its partners must not treat the new foreign worker system as an employee pool they can simply dip into.

The workers' Japanese level is particularly a cause for worry. To obtain a Category 1 visa, applicants must speak Japanese at only a "daily conversational" level. However, anyone working at the Daiichi site must understand a slew of technical terms related to radiation and other facets of the decommissioning process, meaning a very high level of Japanese is absolutely indispensable. If foreign employees begin working there without having learned the necessary terminology, we believe there is a real risk they could be ordered to do jobs that exposed them to radiation.

TEPCO has said it is up to its project partners whether they employ Category 1 foreign workers. In fact, the majority of people at Fukushima Daiichi are employed by one of the firms that make up the layers upon layers of subcontractors working on the decommissioning. Nevertheless, as the company heading the project, TECPO has a responsibility to oversee the conditions of every worker, right down to the bottom of the pyramid.

Furthermore, if a foreign worker has been exposed to radiation overseas, that dose must be added to their sievert count at the plant. However, it is up to the worker to report any previous radiation exposure, which can make it difficult to properly track and manage their doses.

If a worker develops a radiation-related illness after returning to their home country, will they be able to smoothly apply for workers' accident compensation? This is also a serious worry.

If Japan is to accept foreign workers to help decommission the Fukushima Daiichi plant, it is absolutely essential to create the appropriate environment, including measures to boost their Japanese skills and strengthen radiation exposure management.