Safety should be the highest priority of any nuclear power-generating program. Japan, the world's only victim of atomic bombings, has every reason to be particularly sensitive about nuclear safety. However, some of the nation's electric power companies have been found wanting in the safety management of their nuclear plants.

The latest case of gross failure to meet safety standards is exceptionally outrageous because the company implicated is Tokyo Electric Power Co., Japan's largest utility company. It was revealed late last month that Tepco had concealed cracks in reactor shrouds (casings), falsified repair records and submitted erroneous reports to the regulatory authorities from the late '80s to early 1990s. Even more disturbing, two more regional power suppliers, Chubu Electric Power Co. and Tohoku Electric Power Co., admitted last Friday that they had failed to report defects in reactor piping to the Nuclear and Industrial Safety Agency.

All this has confirmed the public suspicion raised by the Tepco coverups that similar attempts might have been made by other power companies. Now it seems reasonably clear that a tendency to tolerate minor faults in reactor systems is fairly widespread in the nuclear power industry. Moreover, as a Tepco investigation has found, coverups have been made "systematically for many years."