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

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

Due to a power outage at our center due to statutory inspection of electrical equipment, we will temporarily suspend updating of monitoring post measurement values ​​from 8:00 to 19:00 on Saturday, October 18, 2025.

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
20:01-21:00, Sat., 11 Oct. 0.0464 0.0367 0.0410
19:01-20:00, Sat., 11 Oct. 0.0435 0.0371 0.0406
18:01-19:00, Sat., 11 Oct. 0.0453 0.0379 0.0412
17:01-18:00, Sat., 11 Oct. 0.0469 0.0387 0.0436
16:01-17:00, Sat., 11 Oct. 0.0471 0.0386 0.0425
15:01-16:00, Sat., 11 Oct. 0.0484 0.0373 0.0428
14:01-15:00, Sat., 11 Oct. 0.0525 0.0416 0.0473
13:01-14:00, Sat., 11 Oct. 0.0516 0.0448 0.0487
12:01-13:00, Sat., 11 Oct. 0.0498 0.0415 0.0457
11:01-12:00, Sat., 11 Oct. 0.0503 0.0405 0.0458
10:01-11:00, Sat., 11 Oct. 0.0500 0.0413 0.0464
09:01-10:00, Sat., 11 Oct. 0.0536 0.0445 0.0492
08:01-09:00, Sat., 11 Oct. 0.0497 0.0391 0.0451
07:01-08:00, Sat., 11 Oct. 0.0428 0.0350 0.0378
06:01-07:00, Sat., 11 Oct. 0.0411 0.0338 0.0366
05:01-06:00, Sat., 11 Oct. 0.0389 0.0339 0.0363
04:01-05:00, Sat., 11 Oct. 0.0388 0.0341 0.0363
03:01-04:00, Sat., 11 Oct. 0.0395 0.0338 0.0365
02:01-03:00, Sat., 11 Oct. 0.0395 0.0343 0.0365
01:01-02:00, Sat., 11 Oct. 0.0397 0.0331 0.0360
00:01-01:00, Sat., 11 Oct. 0.0382 0.0332 0.0360
23:01-24:00, Fri., 10 Oct. 0.0379 0.0334 0.0357
22:01-23:00, Fri., 10 Oct. 0.0372 0.0334 0.0356
21:01-22:00, Fri., 10 Oct. 0.0394 0.0341 0.0360
20:01-21:00, Fri., 10 Oct. 0.0388 0.0334 0.0359
19:01-20:00, Fri., 10 Oct. 0.0391 0.0343 0.0359
18:01-19:00, Fri., 10 Oct. 0.0385 0.0336 0.0359
17:01-18:00, Fri., 10 Oct. 0.0382 0.0340 0.0361
16:01-17:00, Fri., 10 Oct. 0.0394 0.0333 0.0360
15:01-16:00, Fri., 10 Oct. 0.0387 0.0333 0.0360
14:01-15:00, Fri., 10 Oct. 0.0383 0.0341 0.0361
13:01-14:00, Fri., 10 Oct. 0.0380 0.0340 0.0359
12:01-13:00, Fri., 10 Oct. 0.0380 0.0332 0.0357
11:01-12:00, Fri., 10 Oct. 0.0390 0.0333 0.0361
10:01-11:00, Fri., 10 Oct. 0.0374 0.0340 0.0359
09:01-10:00, Fri., 10 Oct. 0.0392 0.0333 0.0362
08:01-09:00, Fri., 10 Oct. 0.0392 0.0346 0.0363
07:01-08:00, Fri., 10 Oct. 0.0400 0.0339 0.0363
06:01-07:00, Fri., 10 Oct. 0.0396 0.0349 0.0364
05:01-06:00, Fri., 10 Oct. 0.0385 0.0341 0.0363
04:01-05:00, Fri., 10 Oct. 0.0409 0.0344 0.0363
03:01-04:00, Fri., 10 Oct. 0.0387 0.0344 0.0360
02:01-03:00, Fri., 10 Oct. 0.0386 0.0335 0.0360
01:01-02:00, Fri., 10 Oct. 0.0402 0.0337 0.0362
00:01-01:00, Fri., 10 Oct. 0.0389 0.0341 0.0361
23:01-24:00, Thu., 09 Oct. 0.0389 0.0340 0.0360
22:01-23:00, Thu., 09 Oct. 0.0375 0.0336 0.0357
21:01-22:00, Thu., 09 Oct. 0.0399 0.0343 0.0362
20:01-21:00, Thu., 09 Oct. 0.0386 0.0340 0.0360
19:01-20:00, Thu., 09 Oct. 0.0393 0.0340 0.0359
18:01-19:00, Thu., 09 Oct. 0.0391 0.0338 0.0359
17:01-18:00, Thu., 09 Oct. 0.0392 0.0339 0.0363
16:01-17:00, Thu., 09 Oct. 0.0389 0.0339 0.0361
15:01-16:00, Thu., 09 Oct. 0.0384 0.0334 0.0361
14:01-15:00, Thu., 09 Oct. 0.0382 0.0344 0.0360
13:01-14:00, Thu., 09 Oct. 0.0404 0.0328 0.0361
12:01-13:00, Thu., 09 Oct. 0.0378 0.0342 0.0361
11:01-12:00, Thu., 09 Oct. 0.0399 0.0340 0.0362
10:01-11:00, Thu., 09 Oct. 0.0373 0.0344 0.0360
09:01-10:00, Thu., 09 Oct. 0.0400 0.0333 0.0359
08:01-09:00, Thu., 09 Oct. 0.0398 0.0334 0.0360
07:01-08:00, Thu., 09 Oct. 0.0404 0.0345 0.0361
06:01-07:00, Thu., 09 Oct. 0.0385 0.0331 0.0361
05:01-06:00, Thu., 09 Oct. 0.0392 0.0338 0.0359
04:01-05:00, Thu., 09 Oct. 0.0381 0.0340 0.0360
03:01-04:00, Thu., 09 Oct. 0.0394 0.0345 0.0362
02:01-03:00, Thu., 09 Oct. 0.0389 0.0333 0.0359
01:01-02:00, Thu., 09 Oct. 0.0385 0.0332 0.0357
00:01-01:00, Thu., 09 Oct. 0.0377 0.0324 0.0357
23:01-24:00, Wed., 08 Oct. 0.0408 0.0335 0.0356
22:01-23:00, Wed., 08 Oct. 0.0398 0.0339 0.0357
21:01-22:00, Wed., 08 Oct. 0.0383 0.0341 0.0358
20:01-21:00, Wed., 08 Oct. 0.0374 0.0339 0.0357
19:01-20:00, Wed., 08 Oct. 0.0389 0.0336 0.0357
18:01-19:00, Wed., 08 Oct. 0.0383 0.0340 0.0355
17:01-18:00, Wed., 08 Oct. 0.0388 0.0335 0.0357
16:01-17:00, Wed., 08 Oct. 0.0388 0.0339 0.0358
15:01-16:00, Wed., 08 Oct. 0.0399 0.0335 0.0357
14:01-15:00, Wed., 08 Oct. 0.0376 0.0335 0.0357
13:01-14:00, Wed., 08 Oct. 0.0380 0.0337 0.0356
12:01-13:00, Wed., 08 Oct. 0.0398 0.0333 0.0355
11:01-12:00, Wed., 08 Oct. 0.0382 0.0330 0.0354
10:01-11:00, Wed., 08 Oct. 0.0381 0.0327 0.0354
09:01-10:00, Wed., 08 Oct. 0.0382 0.0338 0.0357
08:01-09:00, Wed., 08 Oct. 0.0384 0.0336 0.0359
07:01-08:00, Wed., 08 Oct. 0.0391 0.0334 0.0359
06:01-07:00, Wed., 08 Oct. 0.0384 0.0337 0.0358
05:01-06:00, Wed., 08 Oct. 0.0378 0.0333 0.0357
04:01-05:00, Wed., 08 Oct. 0.0384 0.0335 0.0359
03:01-04:00, Wed., 08 Oct. 0.0383 0.0335 0.0357
02:01-03:00, Wed., 08 Oct. 0.0391 0.0341 0.0358
01:01-02:00, Wed., 08 Oct. 0.0374 0.0338 0.0358
00:01-01:00, Wed., 08 Oct. 0.0379 0.0329 0.0359
23:01-24:00, Tue., 07 Oct. 0.0400 0.0338 0.0363
22:01-23:00, Tue., 07 Oct. 0.0381 0.0336 0.0356
21:01-22:00, Tue., 07 Oct. 0.0380 0.0334 0.0357
20:01-21:00, Tue., 07 Oct. 0.0381 0.0341 0.0359
19:01-20:00, Tue., 07 Oct. 0.0376 0.0336 0.0354
18:01-19:00, Tue., 07 Oct. 0.0373 0.0337 0.0355
17:01-18:00, Tue., 07 Oct. 0.0376 0.0336 0.0355
16:01-17:00, Tue., 07 Oct. 0.0373 0.0336 0.0356
15:01-16:00, Tue., 07 Oct. 0.0371 0.0340 0.0355
14:01-15:00, Tue., 07 Oct. 0.0380 0.0339 0.0357
13:01-14:00, Tue., 07 Oct. 0.0388 0.0333 0.0355
12:01-13:00, Tue., 07 Oct. 0.0377 0.0328 0.0353
11:01-12:00, Tue., 07 Oct. 0.0372 0.0327 0.0355
10:01-11:00, Tue., 07 Oct. 0.0389 0.0333 0.0358
09:01-10:00, Tue., 07 Oct. 0.0381 0.0333 0.0359
08:01-09:00, Tue., 07 Oct. 0.0391 0.0340 0.0357
07:01-08:00, Tue., 07 Oct. 0.0383 0.0328 0.0356
06:01-07:00, Tue., 07 Oct. 0.0383 0.0334 0.0358
05:01-06:00, Tue., 07 Oct. 0.0371 0.0325 0.0355
04:01-05:00, Tue., 07 Oct. 0.0379 0.0332 0.0358
03:01-04:00, Tue., 07 Oct. 0.0400 0.0339 0.0359
02:01-03:00, Tue., 07 Oct. 0.0395 0.0336 0.0361
01:01-02:00, Tue., 07 Oct. 0.0385 0.0342 0.0359
00:01-01:00, Tue., 07 Oct. 0.0382 0.0334 0.0358
23:01-24:00, Mon., 06 Oct. 0.0377 0.0338 0.0357
22:01-23:00, Mon., 06 Oct. 0.0394 0.0336 0.0358
21:01-22:00, Mon., 06 Oct. 0.0394 0.0337 0.0358
20:01-21:00, Mon., 06 Oct. 0.0405 0.0339 0.0358
19:01-20:00, Mon., 06 Oct. 0.0378 0.0330 0.0355
18:01-19:00, Mon., 06 Oct. 0.0379 0.0337 0.0357
17:01-18:00, Mon., 06 Oct. 0.0387 0.0344 0.0358
16:01-17:00, Mon., 06 Oct. 0.0406 0.0336 0.0365
15:01-16:00, Mon., 06 Oct. 0.0422 0.0354 0.0386
14:01-15:00, Mon., 06 Oct. 0.0402 0.0340 0.0363
13:01-14:00, Mon., 06 Oct. 0.0383 0.0346 0.0361
12:01-13:00, Mon., 06 Oct. 0.0386 0.0336 0.0360
11:01-12:00, Mon., 06 Oct. 0.0414 0.0343 0.0366
10:01-11:00, Mon., 06 Oct. 0.0392 0.0342 0.0361
09:01-10:00, Mon., 06 Oct. 0.0380 0.0336 0.0358
08:01-09:00, Mon., 06 Oct. 0.0378 0.0341 0.0357
07:01-08:00, Mon., 06 Oct. 0.0384 0.0337 0.0359
06:01-07:00, Mon., 06 Oct. 0.0395 0.0339 0.0362
05:01-06:00, Mon., 06 Oct. 0.0389 0.0328 0.0360
04:01-05:00, Mon., 06 Oct. 0.0388 0.0326 0.0359
03:01-04:00, Mon., 06 Oct. 0.0371 0.0341 0.0360
02:01-03:00, Mon., 06 Oct. 0.0374 0.0341 0.0360
01:01-02:00, Mon., 06 Oct. 0.0385 0.0335 0.0355
00:01-01:00, Mon., 06 Oct. 0.0380 0.0329 0.0354
23:01-24:00, Sun., 05 Oct. 0.0370 0.0333 0.0352
22:01-23:00, Sun., 05 Oct. 0.0374 0.0332 0.0353
21:01-22:00, Sun., 05 Oct. 0.0373 0.0335 0.0355
20:01-21:00, Sun., 05 Oct. 0.0383 0.0337 0.0354
19:01-20:00, Sun., 05 Oct. 0.0371 0.0327 0.0352
18:01-19:00, Sun., 05 Oct. 0.0378 0.0335 0.0354
17:01-18:00, Sun., 05 Oct. 0.0386 0.0332 0.0353
16:01-17:00, Sun., 05 Oct. 0.0376 0.0332 0.0355
15:01-16:00, Sun., 05 Oct. 0.0368 0.0333 0.0352
14:01-15:00, Sun., 05 Oct. 0.0381 0.0331 0.0355
13:01-14:00, Sun., 05 Oct. 0.0376 0.0333 0.0354
12:01-13:00, Sun., 05 Oct. 0.0384 0.0329 0.0354
11:01-12:00, Sun., 05 Oct. 0.0372 0.0329 0.0356
10:01-11:00, Sun., 05 Oct. 0.0375 0.0327 0.0355
09:01-10:00, Sun., 05 Oct. 0.0371 0.0338 0.0356
08:01-09:00, Sun., 05 Oct. 0.0399 0.0336 0.0358
07:01-08:00, Sun., 05 Oct. 0.0378 0.0331 0.0354
06:01-07:00, Sun., 05 Oct. 0.0379 0.0337 0.0357
05:01-06:00, Sun., 05 Oct. 0.0393 0.0337 0.0355
04:01-05:00, Sun., 05 Oct. 0.0374 0.0333 0.0355
03:01-04:00, Sun., 05 Oct. 0.0371 0.0333 0.0353
02:01-03:00, Sun., 05 Oct. 0.0370 0.0331 0.0352
01:01-02:00, Sun., 05 Oct. 0.0393 0.0342 0.0359
00:01-01:00, Sun., 05 Oct. 0.0425 0.0346 0.0373
23:01-24:00, Sat., 04 Oct. 0.0405 0.0345 0.0366
22:01-23:00, Sat., 04 Oct. 0.0414 0.0354 0.0377
21:01-22:00, Sat., 04 Oct. 0.0389 0.0335 0.0358
20:01-21:00, Sat., 04 Oct. 0.0372 0.0330 0.0355
19:01-20:00, Sat., 04 Oct. 0.0388 0.0340 0.0357
18:01-19:00, Sat., 04 Oct. 0.0399 0.0336 0.0362
17:01-18:00, Sat., 04 Oct. 0.0411 0.0351 0.0369
16:01-17:00, Sat., 04 Oct. 0.0369 0.0329 0.0354
15:01-16:00, Sat., 04 Oct. 0.0417 0.0345 0.0365
14:01-15:00, Sat., 04 Oct. 0.0416 0.0353 0.0387
13:01-14:00, Sat., 04 Oct. 0.0500 0.0371 0.0434
12:01-13:00, Sat., 04 Oct. 0.0526 0.0419 0.0477
11:01-12:00, Sat., 04 Oct. 0.0433 0.0341 0.0370
10:01-11:00, Sat., 04 Oct. 0.0405 0.0341 0.0366
09:01-10:00, Sat., 04 Oct. 0.0392 0.0341 0.0363
08:01-09:00, Sat., 04 Oct. 0.0410 0.0350 0.0369
07:01-08:00, Sat., 04 Oct. 0.0391 0.0339 0.0364
06:01-07:00, Sat., 04 Oct. 0.0396 0.0349 0.0370
05:01-06:00, Sat., 04 Oct. 0.0394 0.0347 0.0365
04:01-05:00, Sat., 04 Oct. 0.0382 0.0344 0.0363
03:01-04:00, Sat., 04 Oct. 0.0385 0.0338 0.0360
02:01-03:00, Sat., 04 Oct. 0.0375 0.0338 0.0360
01:01-02:00, Sat., 04 Oct. 0.0375 0.0337 0.0358
00:01-01:00, Sat., 04 Oct. 0.0383 0.0332 0.0357
23:01-24:00, Fri., 03 Oct. 0.0383 0.0337 0.0356
22:01-23:00, Fri., 03 Oct. 0.0392 0.0336 0.0356
21:01-22:00, Fri., 03 Oct. 0.0377 0.0333 0.0356
20:01-21:00, Fri., 03 Oct. 0.0385 0.0333 0.0356
19:01-20:00, Fri., 03 Oct. 0.0372 0.0336 0.0356
18:01-19:00, Fri., 03 Oct. 0.0382 0.0333 0.0355
17:01-18:00, Fri., 03 Oct. 0.0376 0.0328 0.0356
16:01-17:00, Fri., 03 Oct. 0.0390 0.0338 0.0359
15:01-16:00, Fri., 03 Oct. 0.0392 0.0336 0.0358
14:01-15:00, Fri., 03 Oct. 0.0397 0.0339 0.0357
13:01-14:00, Fri., 03 Oct. 0.0381 0.0337 0.0357
12:01-13:00, Fri., 03 Oct. 0.0383 0.0345 0.0359
11:01-12:00, Fri., 03 Oct. 0.0387 0.0341 0.0358
10:01-11:00, Fri., 03 Oct. 0.0373 0.0336 0.0356
09:01-10:00, Fri., 03 Oct. 0.0391 0.0336 0.0359
08:01-09:00, Fri., 03 Oct. 0.0404 0.0336 0.0360
07:01-08:00, Fri., 03 Oct. 0.0394 0.0340 0.0361
06:01-07:00, Fri., 03 Oct. 0.0404 0.0343 0.0365
05:01-06:00, Fri., 03 Oct. 0.0389 0.0344 0.0363
04:01-05:00, Fri., 03 Oct. 0.0390 0.0344 0.0363
03:01-04:00, Fri., 03 Oct. 0.0390 0.0331 0.0365
02:01-03:00, Fri., 03 Oct. 0.0393 0.0341 0.0366
01:01-02:00, Fri., 03 Oct. 0.0404 0.0345 0.0364
00:01-01:00, Fri., 03 Oct. 0.0400 0.0340 0.0359
23:01-24:00, Thu., 02 Oct. 0.0383 0.0341 0.0357
22:01-23:00, Thu., 02 Oct. 0.0400 0.0335 0.0359
21:01-22:00, Thu., 02 Oct. 0.0379 0.0336 0.0357
20:01-21:00, Thu., 02 Oct. 0.0381 0.0331 0.0354
19:01-20:00, Thu., 02 Oct. 0.0369 0.0329 0.0355
18:01-19:00, Thu., 02 Oct. 0.0381 0.0337 0.0360
17:01-18:00, Thu., 02 Oct. 0.0382 0.0335 0.0357
16:01-17:00, Thu., 02 Oct. 0.0386 0.0339 0.0355
15:01-16:00, Thu., 02 Oct. 0.0374 0.0335 0.0354
14:01-15:00, Thu., 02 Oct. 0.0373 0.0324 0.0355
13:01-14:00, Thu., 02 Oct. 0.0369 0.0328 0.0356
12:01-13:00, Thu., 02 Oct. 0.0403 0.0337 0.0359
11:01-12:00, Thu., 02 Oct. 0.0385 0.0341 0.0360
10:01-11:00, Thu., 02 Oct. 0.0385 0.0337 0.0359
09:01-10:00, Thu., 02 Oct. 0.0392 0.0333 0.0361
08:01-09:00, Thu., 02 Oct. 0.0399 0.0336 0.0364
07:01-08:00, Thu., 02 Oct. 0.0404 0.0342 0.0366
06:01-07:00, Thu., 02 Oct. 0.0391 0.0339 0.0364
05:01-06:00, Thu., 02 Oct. 0.0395 0.0340 0.0362
04:01-05:00, Thu., 02 Oct. 0.0374 0.0338 0.0354
03:01-04:00, Thu., 02 Oct. 0.0377 0.0330 0.0357
02:01-03:00, Thu., 02 Oct. 0.0376 0.0319 0.0356
01:01-02:00, Thu., 02 Oct. 0.0373 0.0335 0.0354
00:01-01:00, Thu., 02 Oct. 0.0383 0.0336 0.0356
23:01-24:00, Wed., 01 Oct. 0.0374 0.0331 0.0352
22:01-23:00, Wed., 01 Oct. 0.0375 0.0329 0.0352
21:01-22:00, Wed., 01 Oct. 0.0375 0.0335 0.0355