Radiation doses in the air / Measurement results by the hour (Ota)

We continuously measure radiation doses in the air (air absorbed doses per hour) at monitoring posts. Measurement results can be obtained by the minute, and we gather measurement data and then display them by the hour or by the day.

The maximum value indicates the largest value measured in each time slot (during the hour or during the day), the minimum value the smallest value measured in each time slot, and the average value is the average value for each time slot.

【News about this monitoring post】

We will suspend the provision of data in part or whole of the following time slots by interruption of power supply and relevant facilities due to maintenance and inspection of equipment.

From 10:00 to 13:00 on Tuesday, February 6,2018 Hachioji
From 13:00 to 16:00 on Tuesday, February 6,2018 Kodaira
From 10:00 to 13:00 on Wednesday, February 7,2018 Chofu
From 13:00 to 16:00 on Wednesday, February 7,2018 Ota
From 10:00 to 13:00 on Thursday, February 8,2018 Adachi
From 13:00 to 16:00 on Thursday, February 8,2018 Edogawa
From 10:00 to 13:00 on Friday, February 9,2018 Shinjuku







Shown in µGy/h (microgray per hour)

Gray indicates an amount of energy (absorbed dose) when radiation hits a material object, and 1 gray (Gy) of radiation doses in the air can be converted to 1 sievert (Sv).

Measurement time Dose rate
μGy/h (microgray per hour)
Maximum value Minimum value Average value
13:01-14:00, Tue., 20 Feb. 0.0385 0.0344 0.0360
12:01-13:00, Tue., 20 Feb. 0.0382 0.0346 0.0362
11:01-12:00, Tue., 20 Feb. 0.0387 0.0345 0.0362
10:01-11:00, Tue., 20 Feb. 0.0377 0.0338 0.0358
09:01-10:00, Tue., 20 Feb. 0.0394 0.0335 0.0358
08:01-09:00, Tue., 20 Feb. 0.0385 0.0340 0.0357
07:01-08:00, Tue., 20 Feb. 0.0383 0.0340 0.0359
06:01-07:00, Tue., 20 Feb. 0.0372 0.0340 0.0359
05:01-06:00, Tue., 20 Feb. 0.0380 0.0330 0.0358
04:01-05:00, Tue., 20 Feb. 0.0380 0.0344 0.0360
03:01-04:00, Tue., 20 Feb. 0.0375 0.0335 0.0357
02:01-03:00, Tue., 20 Feb. 0.0384 0.0335 0.0359
01:01-02:00, Tue., 20 Feb. 0.0372 0.0335 0.0357
00:01-01:00, Tue., 20 Feb. 0.0384 0.0340 0.0359
23:01-24:00, Mon., 19 Feb. 0.0374 0.0334 0.0357
22:01-23:00, Mon., 19 Feb. 0.0384 0.0328 0.0356
21:01-22:00, Mon., 19 Feb. 0.0374 0.0336 0.0356
20:01-21:00, Mon., 19 Feb. 0.0386 0.0335 0.0357
19:01-20:00, Mon., 19 Feb. 0.0376 0.0335 0.0357
18:01-19:00, Mon., 19 Feb. 0.0392 0.0342 0.0356
17:01-18:00, Mon., 19 Feb. 0.0374 0.0342 0.0357
16:01-17:00, Mon., 19 Feb. 0.0373 0.0334 0.0357
15:01-16:00, Mon., 19 Feb. 0.0372 0.0335 0.0355
14:01-15:00, Mon., 19 Feb. 0.0389 0.0337 0.0356
13:01-14:00, Mon., 19 Feb. 0.0378 0.0340 0.0357
12:01-13:00, Mon., 19 Feb. 0.0385 0.0343 0.0358
11:01-12:00, Mon., 19 Feb. 0.0374 0.0334 0.0358
10:01-11:00, Mon., 19 Feb. 0.0381 0.0340 0.0358
09:01-10:00, Mon., 19 Feb. 0.0382 0.0340 0.0357
08:01-09:00, Mon., 19 Feb. 0.0374 0.0334 0.0357
07:01-08:00, Mon., 19 Feb. 0.0375 0.0337 0.0357
06:01-07:00, Mon., 19 Feb. 0.0378 0.0329 0.0355
05:01-06:00, Mon., 19 Feb. 0.0372 0.0338 0.0355
04:01-05:00, Mon., 19 Feb. 0.0371 0.0340 0.0355
03:01-04:00, Mon., 19 Feb. 0.0381 0.0332 0.0356
02:01-03:00, Mon., 19 Feb. 0.0381 0.0338 0.0357
01:01-02:00, Mon., 19 Feb. 0.0375 0.0329 0.0355
00:01-01:00, Mon., 19 Feb. 0.0377 0.0336 0.0354
23:01-24:00, Sun., 18 Feb. 0.0385 0.0333 0.0354
22:01-23:00, Sun., 18 Feb. 0.0384 0.0332 0.0353
21:01-22:00, Sun., 18 Feb. 0.0375 0.0325 0.0353
20:01-21:00, Sun., 18 Feb. 0.0375 0.0333 0.0353
19:01-20:00, Sun., 18 Feb. 0.0373 0.0334 0.0355
18:01-19:00, Sun., 18 Feb. 0.0385 0.0333 0.0353
17:01-18:00, Sun., 18 Feb. 0.0382 0.0331 0.0354
16:01-17:00, Sun., 18 Feb. 0.0371 0.0339 0.0356
15:01-16:00, Sun., 18 Feb. 0.0385 0.0334 0.0355
14:01-15:00, Sun., 18 Feb. 0.0373 0.0328 0.0352
13:01-14:00, Sun., 18 Feb. 0.0388 0.0341 0.0358
12:01-13:00, Sun., 18 Feb. 0.0375 0.0338 0.0358
11:01-12:00, Sun., 18 Feb. 0.0382 0.0333 0.0358
10:01-11:00, Sun., 18 Feb. 0.0378 0.0340 0.0358
09:01-10:00, Sun., 18 Feb. 0.0376 0.0335 0.0355
08:01-09:00, Sun., 18 Feb. 0.0385 0.0335 0.0354
07:01-08:00, Sun., 18 Feb. 0.0380 0.0331 0.0354
06:01-07:00, Sun., 18 Feb. 0.0366 0.0337 0.0351
05:01-06:00, Sun., 18 Feb. 0.0378 0.0327 0.0352
04:01-05:00, Sun., 18 Feb. 0.0371 0.0333 0.0353
03:01-04:00, Sun., 18 Feb. 0.0378 0.0339 0.0354
02:01-03:00, Sun., 18 Feb. 0.0379 0.0334 0.0354
01:01-02:00, Sun., 18 Feb. 0.0386 0.0332 0.0356
00:01-01:00, Sun., 18 Feb. 0.0372 0.0339 0.0356
23:01-24:00, Sat., 17 Feb. 0.0379 0.0334 0.0355
22:01-23:00, Sat., 17 Feb. 0.0387 0.0335 0.0356
21:01-22:00, Sat., 17 Feb. 0.0384 0.0338 0.0358
20:01-21:00, Sat., 17 Feb. 0.0385 0.0337 0.0361
19:01-20:00, Sat., 17 Feb. 0.0381 0.0337 0.0358
18:01-19:00, Sat., 17 Feb. 0.0386 0.0337 0.0359
17:01-18:00, Sat., 17 Feb. 0.0394 0.0340 0.0363
16:01-17:00, Sat., 17 Feb. 0.0398 0.0351 0.0368
15:01-16:00, Sat., 17 Feb. 0.0435 0.0365 0.0391
14:01-15:00, Sat., 17 Feb. 0.0421 0.0337 0.0372
13:01-14:00, Sat., 17 Feb. 0.0370 0.0329 0.0354
12:01-13:00, Sat., 17 Feb. 0.0371 0.0329 0.0358
11:01-12:00, Sat., 17 Feb. 0.0385 0.0334 0.0357
10:01-11:00, Sat., 17 Feb. 0.0371 0.0330 0.0355
09:01-10:00, Sat., 17 Feb. 0.0374 0.0328 0.0353
08:01-09:00, Sat., 17 Feb. 0.0378 0.0329 0.0355
07:01-08:00, Sat., 17 Feb. 0.0388 0.0337 0.0356
06:01-07:00, Sat., 17 Feb. 0.0386 0.0339 0.0353
05:01-06:00, Sat., 17 Feb. 0.0370 0.0333 0.0352
04:01-05:00, Sat., 17 Feb. 0.0374 0.0335 0.0354
03:01-04:00, Sat., 17 Feb. 0.0377 0.0338 0.0356
02:01-03:00, Sat., 17 Feb. 0.0373 0.0339 0.0356
01:01-02:00, Sat., 17 Feb. 0.0376 0.0335 0.0353
00:01-01:00, Sat., 17 Feb. 0.0381 0.0337 0.0355
23:01-24:00, Fri., 16 Feb. 0.0371 0.0329 0.0352
22:01-23:00, Fri., 16 Feb. 0.0371 0.0328 0.0350
21:01-22:00, Fri., 16 Feb. 0.0368 0.0334 0.0352
20:01-21:00, Fri., 16 Feb. 0.0372 0.0333 0.0351
19:01-20:00, Fri., 16 Feb. 0.0369 0.0332 0.0351
18:01-19:00, Fri., 16 Feb. 0.0367 0.0332 0.0351
17:01-18:00, Fri., 16 Feb. 0.0384 0.0334 0.0353
16:01-17:00, Fri., 16 Feb. 0.0395 0.0338 0.0355
15:01-16:00, Fri., 16 Feb. 0.0370 0.0331 0.0354
14:01-15:00, Fri., 16 Feb. 0.0382 0.0336 0.0352
13:01-14:00, Fri., 16 Feb. 0.0378 0.0338 0.0358
12:01-13:00, Fri., 16 Feb. 0.0386 0.0334 0.0358
11:01-12:00, Fri., 16 Feb. 0.0376 0.0332 0.0356
10:01-11:00, Fri., 16 Feb. 0.0383 0.0342 0.0358
09:01-10:00, Fri., 16 Feb. 0.0372 0.0339 0.0357
08:01-09:00, Fri., 16 Feb. 0.0381 0.0333 0.0357
07:01-08:00, Fri., 16 Feb. 0.0369 0.0338 0.0355
06:01-07:00, Fri., 16 Feb. 0.0367 0.0337 0.0353
05:01-06:00, Fri., 16 Feb. 0.0381 0.0332 0.0354
04:01-05:00, Fri., 16 Feb. 0.0384 0.0340 0.0356
03:01-04:00, Fri., 16 Feb. 0.0370 0.0336 0.0352
02:01-03:00, Fri., 16 Feb. 0.0368 0.0339 0.0353
01:01-02:00, Fri., 16 Feb. 0.0372 0.0334 0.0357
00:01-01:00, Fri., 16 Feb. 0.0388 0.0333 0.0358
23:01-24:00, Thu., 15 Feb. 0.0379 0.0341 0.0358
22:01-23:00, Thu., 15 Feb. 0.0369 0.0331 0.0355
21:01-22:00, Thu., 15 Feb. 0.0375 0.0335 0.0355
20:01-21:00, Thu., 15 Feb. 0.0375 0.0336 0.0358
19:01-20:00, Thu., 15 Feb. 0.0380 0.0333 0.0355
18:01-19:00, Thu., 15 Feb. 0.0381 0.0329 0.0356
17:01-18:00, Thu., 15 Feb. 0.0379 0.0336 0.0356
16:01-17:00, Thu., 15 Feb. 0.0373 0.0338 0.0356
15:01-16:00, Thu., 15 Feb. 0.0391 0.0339 0.0357
14:01-15:00, Thu., 15 Feb. 0.0373 0.0339 0.0357
13:01-14:00, Thu., 15 Feb. 0.0395 0.0343 0.0360
12:01-13:00, Thu., 15 Feb. 0.0375 0.0330 0.0359
11:01-12:00, Thu., 15 Feb. 0.0389 0.0328 0.0364
10:01-11:00, Thu., 15 Feb. 0.0382 0.0338 0.0360
09:01-10:00, Thu., 15 Feb. 0.0387 0.0343 0.0359
08:01-09:00, Thu., 15 Feb. 0.0396 0.0336 0.0359
07:01-08:00, Thu., 15 Feb. 0.0385 0.0338 0.0356
06:01-07:00, Thu., 15 Feb. 0.0387 0.0339 0.0358
05:01-06:00, Thu., 15 Feb. 0.0373 0.0336 0.0354
04:01-05:00, Thu., 15 Feb. 0.0383 0.0329 0.0355
03:01-04:00, Thu., 15 Feb. 0.0387 0.0331 0.0356
02:01-03:00, Thu., 15 Feb. 0.0384 0.0339 0.0356
01:01-02:00, Thu., 15 Feb. 0.0382 0.0337 0.0358
00:01-01:00, Thu., 15 Feb. 0.0383 0.0336 0.0354
23:01-24:00, Wed., 14 Feb. 0.0372 0.0325 0.0355
22:01-23:00, Wed., 14 Feb. 0.0375 0.0339 0.0357
21:01-22:00, Wed., 14 Feb. 0.0383 0.0331 0.0352
20:01-21:00, Wed., 14 Feb. 0.0371 0.0334 0.0351
19:01-20:00, Wed., 14 Feb. 0.0376 0.0334 0.0354
18:01-19:00, Wed., 14 Feb. 0.0374 0.0323 0.0351
17:01-18:00, Wed., 14 Feb. 0.0364 0.0334 0.0350
16:01-17:00, Wed., 14 Feb. 0.0372 0.0330 0.0351
15:01-16:00, Wed., 14 Feb. 0.0371 0.0331 0.0353
14:01-15:00, Wed., 14 Feb. 0.0372 0.0333 0.0353
13:01-14:00, Wed., 14 Feb. 0.0388 0.0337 0.0355
12:01-13:00, Wed., 14 Feb. 0.0377 0.0339 0.0355
11:01-12:00, Wed., 14 Feb. 0.0370 0.0339 0.0356
10:01-11:00, Wed., 14 Feb. 0.0379 0.0333 0.0357
09:01-10:00, Wed., 14 Feb. 0.0373 0.0337 0.0358
08:01-09:00, Wed., 14 Feb. 0.0377 0.0343 0.0359
07:01-08:00, Wed., 14 Feb. 0.0384 0.0341 0.0357
06:01-07:00, Wed., 14 Feb. 0.0380 0.0328 0.0353
05:01-06:00, Wed., 14 Feb. 0.0370 0.0333 0.0351
04:01-05:00, Wed., 14 Feb. 0.0383 0.0334 0.0352
03:01-04:00, Wed., 14 Feb. 0.0372 0.0340 0.0355
02:01-03:00, Wed., 14 Feb. 0.0370 0.0336 0.0355
01:01-02:00, Wed., 14 Feb. 0.0370 0.0331 0.0352
00:01-01:00, Wed., 14 Feb. 0.0371 0.0335 0.0351
23:01-24:00, Tue., 13 Feb. 0.0368 0.0335 0.0352
22:01-23:00, Tue., 13 Feb. 0.0370 0.0333 0.0354
21:01-22:00, Tue., 13 Feb. 0.0371 0.0329 0.0357
20:01-21:00, Tue., 13 Feb. 0.0381 0.0330 0.0353
19:01-20:00, Tue., 13 Feb. 0.0372 0.0331 0.0355
18:01-19:00, Tue., 13 Feb. 0.0372 0.0334 0.0355
17:01-18:00, Tue., 13 Feb. 0.0378 0.0334 0.0355
16:01-17:00, Tue., 13 Feb. 0.0377 0.0333 0.0355
15:01-16:00, Tue., 13 Feb. 0.0380 0.0330 0.0354
14:01-15:00, Tue., 13 Feb. 0.0378 0.0331 0.0356
13:01-14:00, Tue., 13 Feb. 0.0384 0.0338 0.0357
12:01-13:00, Tue., 13 Feb. 0.0377 0.0331 0.0355
11:01-12:00, Tue., 13 Feb. 0.0385 0.0332 0.0355
10:01-11:00, Tue., 13 Feb. 0.0394 0.0330 0.0353
09:01-10:00, Tue., 13 Feb. 0.0375 0.0336 0.0355
08:01-09:00, Tue., 13 Feb. 0.0370 0.0334 0.0352
07:01-08:00, Tue., 13 Feb. 0.0376 0.0334 0.0353
06:01-07:00, Tue., 13 Feb. 0.0372 0.0322 0.0354
05:01-06:00, Tue., 13 Feb. 0.0387 0.0328 0.0351
04:01-05:00, Tue., 13 Feb. 0.0369 0.0333 0.0351
03:01-04:00, Tue., 13 Feb. 0.0373 0.0335 0.0351
02:01-03:00, Tue., 13 Feb. 0.0373 0.0328 0.0350
01:01-02:00, Tue., 13 Feb. 0.0376 0.0319 0.0350
00:01-01:00, Tue., 13 Feb. 0.0375 0.0329 0.0351
23:01-24:00, Mon., 12 Feb. 0.0369 0.0331 0.0351
22:01-23:00, Mon., 12 Feb. 0.0373 0.0339 0.0354
21:01-22:00, Mon., 12 Feb. 0.0370 0.0327 0.0351
20:01-21:00, Mon., 12 Feb. 0.0372 0.0332 0.0352
19:01-20:00, Mon., 12 Feb. 0.0373 0.0332 0.0351
18:01-19:00, Mon., 12 Feb. 0.0381 0.0330 0.0355
17:01-18:00, Mon., 12 Feb. 0.0374 0.0332 0.0351
16:01-17:00, Mon., 12 Feb. 0.0376 0.0326 0.0354
15:01-16:00, Mon., 12 Feb. 0.0378 0.0331 0.0353
14:01-15:00, Mon., 12 Feb. 0.0373 0.0330 0.0355
13:01-14:00, Mon., 12 Feb. 0.0378 0.0334 0.0358
12:01-13:00, Mon., 12 Feb. 0.0386 0.0333 0.0358
11:01-12:00, Mon., 12 Feb. 0.0387 0.0335 0.0357
10:01-11:00, Mon., 12 Feb. 0.0376 0.0329 0.0356
09:01-10:00, Mon., 12 Feb. 0.0369 0.0332 0.0354
08:01-09:00, Mon., 12 Feb. 0.0373 0.0334 0.0353
07:01-08:00, Mon., 12 Feb. 0.0369 0.0331 0.0351
06:01-07:00, Mon., 12 Feb. 0.0373 0.0337 0.0352
05:01-06:00, Mon., 12 Feb. 0.0368 0.0326 0.0354
04:01-05:00, Mon., 12 Feb. 0.0371 0.0333 0.0353
03:01-04:00, Mon., 12 Feb. 0.0396 0.0330 0.0353
02:01-03:00, Mon., 12 Feb. 0.0374 0.0329 0.0354
01:01-02:00, Mon., 12 Feb. 0.0383 0.0333 0.0353
00:01-01:00, Mon., 12 Feb. 0.0366 0.0328 0.0350
23:01-24:00, Sun., 11 Feb. 0.0371 0.0331 0.0350
22:01-23:00, Sun., 11 Feb. 0.0373 0.0334 0.0353
21:01-22:00, Sun., 11 Feb. 0.0372 0.0331 0.0352
20:01-21:00, Sun., 11 Feb. 0.0373 0.0336 0.0354
19:01-20:00, Sun., 11 Feb. 0.0367 0.0334 0.0351
18:01-19:00, Sun., 11 Feb. 0.0380 0.0339 0.0355
17:01-18:00, Sun., 11 Feb. 0.0382 0.0344 0.0356
16:01-17:00, Sun., 11 Feb. 0.0392 0.0330 0.0355
15:01-16:00, Sun., 11 Feb. 0.0370 0.0333 0.0355
14:01-15:00, Sun., 11 Feb. 0.0371 0.0338 0.0355
13:01-14:00, Sun., 11 Feb. 0.0375 0.0337 0.0355
12:01-13:00, Sun., 11 Feb. 0.0380 0.0339 0.0357
11:01-12:00, Sun., 11 Feb. 0.0378 0.0343 0.0358
10:01-11:00, Sun., 11 Feb. 0.0397 0.0334 0.0360
09:01-10:00, Sun., 11 Feb. 0.0384 0.0329 0.0358
08:01-09:00, Sun., 11 Feb. 0.0396 0.0337 0.0359
07:01-08:00, Sun., 11 Feb. 0.0377 0.0336 0.0359
06:01-07:00, Sun., 11 Feb. 0.0376 0.0339 0.0359
05:01-06:00, Sun., 11 Feb. 0.0381 0.0338 0.0357
04:01-05:00, Sun., 11 Feb. 0.0373 0.0336 0.0356
03:01-04:00, Sun., 11 Feb. 0.0378 0.0328 0.0354
02:01-03:00, Sun., 11 Feb. 0.0371 0.0328 0.0352
01:01-02:00, Sun., 11 Feb. 0.0365 0.0334 0.0350
00:01-01:00, Sun., 11 Feb. 0.0379 0.0337 0.0357
23:01-24:00, Sat., 10 Feb. 0.0424 0.0350 0.0382
22:01-23:00, Sat., 10 Feb. 0.0445 0.0373 0.0418
21:01-22:00, Sat., 10 Feb. 0.0440 0.0362 0.0397
20:01-21:00, Sat., 10 Feb. 0.0403 0.0349 0.0375
19:01-20:00, Sat., 10 Feb. 0.0392 0.0333 0.0357
18:01-19:00, Sat., 10 Feb. 0.0377 0.0336 0.0355
17:01-18:00, Sat., 10 Feb. 0.0378 0.0337 0.0356
16:01-17:00, Sat., 10 Feb. 0.0373 0.0330 0.0352
15:01-16:00, Sat., 10 Feb. 0.0378 0.0335 0.0358
14:01-15:00, Sat., 10 Feb. 0.0391 0.0336 0.0359