More Related Content More from International Atomic Energy Agency More from International Atomic Energy Agency (20) Technical Briefing on Radiological Situation in Japan after 2011 Earthquake2. On-site situation Fukushima Dai-ichi The highest recorded value at the site was 400 mSv/h. This was recorded on 15 th March at a different on-site location and is not included in the graph. 4. Gamma-dose rate at Ibaragi, 120 km South West (microSv/h) 14 March 17 March 16 March 15 March Background Off-site situation 5. Gamma-dose rate at Togichi, 140 km South West (microSv/h) Background 14 March 15 March 16 March 17 March 6. Gamma-dose rate at Chiba 218 km South West (microSv/h) 14 March 15 March 16 March 17 March Background 7. Gamma-dose rate at Tokyo, 230 km South West (microSv/h) Background 14 March 15 March 16 March 17 March