Levels of radiation in the study area ranged from 0.02 to 92.90 micro Sieverts per hour. (sciencedaily.com)
It usually only occurs when someone has been exposed to about one sievert of radiation over a relatively short period of time. (scientificamerican.com)
Okedele hinted that as of October 30, 2015, the Japan Times «reported that Tokyo Electric power Company (TEPCO) has detected high level Radiation at 9.4 Sieverts outside Reactor containment Vessel # 2. (nigeriapoliticsonline.com)