11m 56s: Lenght

ambient radiation around this area 0.07μSv/h ambient radiation nearby the micro hot spot 0.13μSv/h (1meter) ambient radiation (50cm) 0.25μSv/h surface of the spot 1.31μSv/h location↓ https://www.google.co.jp/maps/place/35%C2%B046'12.9%22N+139%C2%B049'29.6%22E/@35.7701884,139.8248805,21z/data=!4m2!3m1!1s0x0:0x0?hl=ja