Quake scale may be underestimated in calculations for nuclear plants: Ex-NRA official

Nuclear Regulation Authority (NRA) former deputy chairman Kunihiko Shimazaki asked the nuclear power watchdog on June 16 to recalculate the maximum possible earthquake estimate -- known as the standard ground motion -- for some nuclear plants in western Japan using a different formula, since the current calculation may include underestimated figures. 
http://mainichi.jp/english/articles/20160617/p2a/00m/0na/010000c