Like others in the industry, the firm had suspended sending invitations to panellists in the Tohoku prefectures of Aomori, Iwate, Miyagi, Akita, Yamagata, Fukushima and Ibaraki, the areas hit hardest in the disaster.

RPA chief executive Shogo Nakazato said that other panel companies were also resuming services in the region. “There’s no strict binding in the industry, so each company is trying its own careful approach to the region to find out how their panels respond,” he said.

“We’ll recover gradually from some areas with relatively little damage, although the continuing aftershocks may interrupt the effort.”