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

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.

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
21:01-22:00, Fri., 06 Mar. 0.0297 0.0255 0.0277
20:01-21:00, Fri., 06 Mar. 0.0294 0.0253 0.0274
19:01-20:00, Fri., 06 Mar. 0.0304 0.0256 0.0275
18:01-19:00, Fri., 06 Mar. 0.0296 0.0258 0.0276
17:01-18:00, Fri., 06 Mar. 0.0307 0.0255 0.0276
16:01-17:00, Fri., 06 Mar. 0.0299 0.0253 0.0277
15:01-16:00, Fri., 06 Mar. 0.0301 0.0256 0.0277
14:01-15:00, Fri., 06 Mar. 0.0302 0.0256 0.0276
13:01-14:00, Fri., 06 Mar. 0.0301 0.0258 0.0279
12:01-13:00, Fri., 06 Mar. 0.0308 0.0259 0.0278
11:01-12:00, Fri., 06 Mar. 0.0293 0.0260 0.0277
10:01-11:00, Fri., 06 Mar. 0.0308 0.0258 0.0279
09:01-10:00, Fri., 06 Mar. 0.0300 0.0258 0.0283
08:01-09:00, Fri., 06 Mar. 0.0304 0.0264 0.0283
07:01-08:00, Fri., 06 Mar. 0.0308 0.0253 0.0281
06:01-07:00, Fri., 06 Mar. 0.0300 0.0260 0.0279
05:01-06:00, Fri., 06 Mar. 0.0297 0.0249 0.0275
04:01-05:00, Fri., 06 Mar. 0.0290 0.0255 0.0273
03:01-04:00, Fri., 06 Mar. 0.0295 0.0254 0.0273
02:01-03:00, Fri., 06 Mar. 0.0292 0.0249 0.0272
01:01-02:00, Fri., 06 Mar. 0.0298 0.0253 0.0272
00:01-01:00, Fri., 06 Mar. 0.0295 0.0254 0.0271
23:01-24:00, Thu., 05 Mar. 0.0297 0.0250 0.0271
22:01-23:00, Thu., 05 Mar. 0.0289 0.0251 0.0273
21:01-22:00, Thu., 05 Mar. 0.0300 0.0249 0.0271
20:01-21:00, Thu., 05 Mar. 0.0288 0.0245 0.0271
19:01-20:00, Thu., 05 Mar. 0.0292 0.0248 0.0272
18:01-19:00, Thu., 05 Mar. 0.0288 0.0251 0.0271
17:01-18:00, Thu., 05 Mar. 0.0294 0.0247 0.0270
16:01-17:00, Thu., 05 Mar. 0.0293 0.0250 0.0272
15:01-16:00, Thu., 05 Mar. 0.0293 0.0255 0.0273
14:01-15:00, Thu., 05 Mar. 0.0304 0.0252 0.0277
13:01-14:00, Thu., 05 Mar. 0.0304 0.0256 0.0276
12:01-13:00, Thu., 05 Mar. 0.0297 0.0253 0.0274
11:01-12:00, Thu., 05 Mar. 0.0290 0.0256 0.0274
10:01-11:00, Thu., 05 Mar. 0.0297 0.0251 0.0274
09:01-10:00, Thu., 05 Mar. 0.0298 0.0254 0.0272
08:01-09:00, Thu., 05 Mar. 0.0305 0.0256 0.0274
07:01-08:00, Thu., 05 Mar. 0.0293 0.0252 0.0271
06:01-07:00, Thu., 05 Mar. 0.0297 0.0256 0.0272
05:01-06:00, Thu., 05 Mar. 0.0302 0.0251 0.0273
04:01-05:00, Thu., 05 Mar. 0.0291 0.0249 0.0272
03:01-04:00, Thu., 05 Mar. 0.0291 0.0257 0.0273
02:01-03:00, Thu., 05 Mar. 0.0287 0.0242 0.0271
01:01-02:00, Thu., 05 Mar. 0.0296 0.0256 0.0273
00:01-01:00, Thu., 05 Mar. 0.0293 0.0252 0.0272
23:01-24:00, Wed., 04 Mar. 0.0289 0.0252 0.0270
22:01-23:00, Wed., 04 Mar. 0.0289 0.0250 0.0269
21:01-22:00, Wed., 04 Mar. 0.0291 0.0250 0.0271
20:01-21:00, Wed., 04 Mar. 0.0292 0.0256 0.0272
19:01-20:00, Wed., 04 Mar. 0.0290 0.0249 0.0272
18:01-19:00, Wed., 04 Mar. 0.0287 0.0251 0.0269
17:01-18:00, Wed., 04 Mar. 0.0294 0.0249 0.0272
16:01-17:00, Wed., 04 Mar. 0.0292 0.0245 0.0273
15:01-16:00, Wed., 04 Mar. 0.0302 0.0259 0.0275
14:01-15:00, Wed., 04 Mar. 0.0298 0.0251 0.0277
13:01-14:00, Wed., 04 Mar. 0.0302 0.0259 0.0278
12:01-13:00, Wed., 04 Mar. 0.0298 0.0263 0.0281
11:01-12:00, Wed., 04 Mar. 0.0303 0.0259 0.0281
10:01-11:00, Wed., 04 Mar. 0.0306 0.0261 0.0281
09:01-10:00, Wed., 04 Mar. 0.0308 0.0269 0.0287
08:01-09:00, Wed., 04 Mar. 0.0311 0.0271 0.0293
07:01-08:00, Wed., 04 Mar. 0.0318 0.0276 0.0294
06:01-07:00, Wed., 04 Mar. 0.0318 0.0273 0.0297
05:01-06:00, Wed., 04 Mar. 0.0358 0.0297 0.0330
04:01-05:00, Wed., 04 Mar. 0.0402 0.0325 0.0365
03:01-04:00, Wed., 04 Mar. 0.0433 0.0381 0.0411
02:01-03:00, Wed., 04 Mar. 0.0478 0.0386 0.0435
01:01-02:00, Wed., 04 Mar. 0.0544 0.0450 0.0497
00:01-01:00, Wed., 04 Mar. 0.0543 0.0485 0.0513
23:01-24:00, Tue., 03 Mar. 0.0508 0.0349 0.0444
22:01-23:00, Tue., 03 Mar. 0.0481 0.0362 0.0421
21:01-22:00, Tue., 03 Mar. 0.0504 0.0410 0.0465
20:01-21:00, Tue., 03 Mar. 0.0440 0.0374 0.0409
19:01-20:00, Tue., 03 Mar. 0.0477 0.0403 0.0441
18:01-19:00, Tue., 03 Mar. 0.0479 0.0397 0.0439
17:01-18:00, Tue., 03 Mar. 0.0464 0.0418 0.0442
16:01-17:00, Tue., 03 Mar. 0.0471 0.0395 0.0427
15:01-16:00, Tue., 03 Mar. 0.0412 0.0370 0.0392
14:01-15:00, Tue., 03 Mar. 0.0416 0.0367 0.0394
13:01-14:00, Tue., 03 Mar. 0.0436 0.0373 0.0402
12:01-13:00, Tue., 03 Mar. 0.0426 0.0367 0.0393
11:01-12:00, Tue., 03 Mar. 0.0441 0.0388 0.0414
10:01-11:00, Tue., 03 Mar. 0.0405 0.0339 0.0373
09:01-10:00, Tue., 03 Mar. 0.0391 0.0330 0.0356
08:01-09:00, Tue., 03 Mar. 0.0386 0.0322 0.0356
07:01-08:00, Tue., 03 Mar. 0.0372 0.0320 0.0345
06:01-07:00, Tue., 03 Mar. 0.0357 0.0297 0.0328
05:01-06:00, Tue., 03 Mar. 0.0335 0.0273 0.0309
04:01-05:00, Tue., 03 Mar. 0.0303 0.0258 0.0279
03:01-04:00, Tue., 03 Mar. 0.0310 0.0254 0.0278
02:01-03:00, Tue., 03 Mar. 0.0294 0.0256 0.0276
01:01-02:00, Tue., 03 Mar. 0.0301 0.0256 0.0278
00:01-01:00, Tue., 03 Mar. 0.0303 0.0252 0.0275
23:01-24:00, Mon., 02 Mar. 0.0302 0.0238 0.0274
22:01-23:00, Mon., 02 Mar. 0.0298 0.0260 0.0275
21:01-22:00, Mon., 02 Mar. 0.0300 0.0256 0.0276
20:01-21:00, Mon., 02 Mar. 0.0289 0.0249 0.0275
19:01-20:00, Mon., 02 Mar. 0.0297 0.0262 0.0276
18:01-19:00, Mon., 02 Mar. 0.0297 0.0256 0.0275
17:01-18:00, Mon., 02 Mar. 0.0306 0.0259 0.0279
16:01-17:00, Mon., 02 Mar. 0.0298 0.0262 0.0279
15:01-16:00, Mon., 02 Mar. 0.0298 0.0257 0.0278
14:01-15:00, Mon., 02 Mar. 0.0299 0.0259 0.0281
13:01-14:00, Mon., 02 Mar. 0.0305 0.0259 0.0283
12:01-13:00, Mon., 02 Mar. 0.0307 0.0264 0.0286
11:01-12:00, Mon., 02 Mar. 0.0308 0.0262 0.0287
10:01-11:00, Mon., 02 Mar. 0.0303 0.0259 0.0285
09:01-10:00, Mon., 02 Mar. 0.0313 0.0269 0.0288
08:01-09:00, Mon., 02 Mar. 0.0314 0.0271 0.0288
07:01-08:00, Mon., 02 Mar. 0.0310 0.0259 0.0286
06:01-07:00, Mon., 02 Mar. 0.0308 0.0255 0.0287
05:01-06:00, Mon., 02 Mar. 0.0307 0.0263 0.0284
04:01-05:00, Mon., 02 Mar. 0.0312 0.0264 0.0285
03:01-04:00, Mon., 02 Mar. 0.0310 0.0263 0.0282
02:01-03:00, Mon., 02 Mar. 0.0304 0.0264 0.0285
01:01-02:00, Mon., 02 Mar. 0.0299 0.0253 0.0283
00:01-01:00, Mon., 02 Mar. 0.0304 0.0259 0.0282
23:01-24:00, Sun., 01 Mar. 0.0304 0.0258 0.0278
22:01-23:00, Sun., 01 Mar. 0.0297 0.0252 0.0276
21:01-22:00, Sun., 01 Mar. 0.0314 0.0250 0.0278
20:01-21:00, Sun., 01 Mar. 0.0289 0.0258 0.0275
19:01-20:00, Sun., 01 Mar. 0.0292 0.0249 0.0274
18:01-19:00, Sun., 01 Mar. 0.0291 0.0243 0.0273
17:01-18:00, Sun., 01 Mar. 0.0299 0.0256 0.0274
16:01-17:00, Sun., 01 Mar. 0.0304 0.0254 0.0275
15:01-16:00, Sun., 01 Mar. 0.0295 0.0249 0.0275
14:01-15:00, Sun., 01 Mar. 0.0298 0.0254 0.0276
13:01-14:00, Sun., 01 Mar. 0.0298 0.0260 0.0276
12:01-13:00, Sun., 01 Mar. 0.0297 0.0253 0.0276
11:01-12:00, Sun., 01 Mar. 0.0304 0.0256 0.0277
10:01-11:00, Sun., 01 Mar. 0.0308 0.0259 0.0277
09:01-10:00, Sun., 01 Mar. 0.0301 0.0259 0.0276
08:01-09:00, Sun., 01 Mar. 0.0297 0.0255 0.0277
07:01-08:00, Sun., 01 Mar. 0.0295 0.0256 0.0275
06:01-07:00, Sun., 01 Mar. 0.0294 0.0256 0.0274
05:01-06:00, Sun., 01 Mar. 0.0300 0.0260 0.0278
04:01-05:00, Sun., 01 Mar. 0.0297 0.0253 0.0276
03:01-04:00, Sun., 01 Mar. 0.0304 0.0251 0.0277
02:01-03:00, Sun., 01 Mar. 0.0298 0.0257 0.0275
01:01-02:00, Sun., 01 Mar. 0.0294 0.0252 0.0275
00:01-01:00, Sun., 01 Mar. 0.0301 0.0258 0.0278
23:01-24:00, Sat., 28 Feb. 0.0296 0.0245 0.0275
22:01-23:00, Sat., 28 Feb. 0.0300 0.0250 0.0272
21:01-22:00, Sat., 28 Feb. 0.0298 0.0247 0.0271
20:01-21:00, Sat., 28 Feb. 0.0291 0.0251 0.0273
19:01-20:00, Sat., 28 Feb. 0.0296 0.0246 0.0274
18:01-19:00, Sat., 28 Feb. 0.0291 0.0242 0.0273
17:01-18:00, Sat., 28 Feb. 0.0293 0.0253 0.0273
16:01-17:00, Sat., 28 Feb. 0.0303 0.0255 0.0275
15:01-16:00, Sat., 28 Feb. 0.0296 0.0250 0.0277
14:01-15:00, Sat., 28 Feb. 0.0305 0.0250 0.0277
13:01-14:00, Sat., 28 Feb. 0.0294 0.0261 0.0277
12:01-13:00, Sat., 28 Feb. 0.0300 0.0256 0.0278
11:01-12:00, Sat., 28 Feb. 0.0304 0.0260 0.0280
10:01-11:00, Sat., 28 Feb. 0.0302 0.0264 0.0283
09:01-10:00, Sat., 28 Feb. 0.0311 0.0264 0.0285
08:01-09:00, Sat., 28 Feb. 0.0311 0.0261 0.0286
07:01-08:00, Sat., 28 Feb. 0.0311 0.0271 0.0287
06:01-07:00, Sat., 28 Feb. 0.0303 0.0263 0.0286
05:01-06:00, Sat., 28 Feb. 0.0297 0.0249 0.0277
04:01-05:00, Sat., 28 Feb. 0.0296 0.0249 0.0274
03:01-04:00, Sat., 28 Feb. 0.0299 0.0258 0.0273
02:01-03:00, Sat., 28 Feb. 0.0297 0.0247 0.0273
01:01-02:00, Sat., 28 Feb. 0.0300 0.0252 0.0275
00:01-01:00, Sat., 28 Feb. 0.0306 0.0260 0.0276
23:01-24:00, Fri., 27 Feb. 0.0297 0.0255 0.0275
22:01-23:00, Fri., 27 Feb. 0.0296 0.0259 0.0276
21:01-22:00, Fri., 27 Feb. 0.0290 0.0257 0.0274
20:01-21:00, Fri., 27 Feb. 0.0287 0.0253 0.0274
19:01-20:00, Fri., 27 Feb. 0.0297 0.0249 0.0272
18:01-19:00, Fri., 27 Feb. 0.0286 0.0248 0.0273
17:01-18:00, Fri., 27 Feb. 0.0298 0.0254 0.0272
16:01-17:00, Fri., 27 Feb. 0.0304 0.0250 0.0275
15:01-16:00, Fri., 27 Feb. 0.0302 0.0256 0.0275
14:01-15:00, Fri., 27 Feb. 0.0290 0.0256 0.0275
13:01-14:00, Fri., 27 Feb. 0.0304 0.0251 0.0277
12:01-13:00, Fri., 27 Feb. 0.0300 0.0254 0.0277
11:01-12:00, Fri., 27 Feb. 0.0301 0.0261 0.0278
10:01-11:00, Fri., 27 Feb. 0.0295 0.0256 0.0277
09:01-10:00, Fri., 27 Feb. 0.0297 0.0256 0.0277
08:01-09:00, Fri., 27 Feb. 0.0302 0.0256 0.0275
07:01-08:00, Fri., 27 Feb. 0.0296 0.0260 0.0275
06:01-07:00, Fri., 27 Feb. 0.0287 0.0255 0.0274
05:01-06:00, Fri., 27 Feb. 0.0306 0.0249 0.0274
04:01-05:00, Fri., 27 Feb. 0.0294 0.0249 0.0272
03:01-04:00, Fri., 27 Feb. 0.0288 0.0249 0.0271
02:01-03:00, Fri., 27 Feb. 0.0292 0.0249 0.0273
01:01-02:00, Fri., 27 Feb. 0.0288 0.0252 0.0271
00:01-01:00, Fri., 27 Feb. 0.0294 0.0252 0.0272
23:01-24:00, Thu., 26 Feb. 0.0296 0.0248 0.0272
22:01-23:00, Thu., 26 Feb. 0.0292 0.0257 0.0272
21:01-22:00, Thu., 26 Feb. 0.0298 0.0252 0.0270
20:01-21:00, Thu., 26 Feb. 0.0298 0.0249 0.0273
19:01-20:00, Thu., 26 Feb. 0.0290 0.0249 0.0270
18:01-19:00, Thu., 26 Feb. 0.0291 0.0249 0.0271
17:01-18:00, Thu., 26 Feb. 0.0293 0.0245 0.0270
16:01-17:00, Thu., 26 Feb. 0.0296 0.0256 0.0273
15:01-16:00, Thu., 26 Feb. 0.0293 0.0252 0.0274
14:01-15:00, Thu., 26 Feb. 0.0296 0.0254 0.0273
13:01-14:00, Thu., 26 Feb. 0.0297 0.0246 0.0273
12:01-13:00, Thu., 26 Feb. 0.0293 0.0252 0.0272
11:01-12:00, Thu., 26 Feb. 0.0296 0.0256 0.0275
10:01-11:00, Thu., 26 Feb. 0.0298 0.0256 0.0273
09:01-10:00, Thu., 26 Feb. 0.0300 0.0249 0.0272
08:01-09:00, Thu., 26 Feb. 0.0297 0.0250 0.0272
07:01-08:00, Thu., 26 Feb. 0.0291 0.0249 0.0275
06:01-07:00, Thu., 26 Feb. 0.0301 0.0263 0.0284
05:01-06:00, Thu., 26 Feb. 0.0307 0.0252 0.0286
04:01-05:00, Thu., 26 Feb. 0.0319 0.0271 0.0294
03:01-04:00, Thu., 26 Feb. 0.0360 0.0301 0.0325
02:01-03:00, Thu., 26 Feb. 0.0381 0.0326 0.0351
01:01-02:00, Thu., 26 Feb. 0.0408 0.0338 0.0376
00:01-01:00, Thu., 26 Feb. 0.0409 0.0337 0.0369
23:01-24:00, Wed., 25 Feb. 0.0379 0.0335 0.0357
22:01-23:00, Wed., 25 Feb. 0.0389 0.0334 0.0358
21:01-22:00, Wed., 25 Feb. 0.0395 0.0348 0.0369
20:01-21:00, Wed., 25 Feb. 0.0384 0.0330 0.0360
19:01-20:00, Wed., 25 Feb. 0.0381 0.0328 0.0355
18:01-19:00, Wed., 25 Feb. 0.0377 0.0315 0.0343
17:01-18:00, Wed., 25 Feb. 0.0356 0.0310 0.0338
16:01-17:00, Wed., 25 Feb. 0.0345 0.0301 0.0326
15:01-16:00, Wed., 25 Feb. 0.0376 0.0309 0.0341
14:01-15:00, Wed., 25 Feb. 0.0381 0.0324 0.0351
13:01-14:00, Wed., 25 Feb. 0.0429 0.0353 0.0390
12:01-13:00, Wed., 25 Feb. 0.0451 0.0389 0.0421
11:01-12:00, Wed., 25 Feb. 0.0436 0.0372 0.0396
10:01-11:00, Wed., 25 Feb. 0.0398 0.0291 0.0336
09:01-10:00, Wed., 25 Feb. 0.0343 0.0291 0.0319
08:01-09:00, Wed., 25 Feb. 0.0332 0.0286 0.0312
07:01-08:00, Wed., 25 Feb. 0.0322 0.0284 0.0303
06:01-07:00, Wed., 25 Feb. 0.0307 0.0258 0.0287
05:01-06:00, Wed., 25 Feb. 0.0311 0.0263 0.0287
04:01-05:00, Wed., 25 Feb. 0.0311 0.0268 0.0286
03:01-04:00, Wed., 25 Feb. 0.0308 0.0265 0.0285
02:01-03:00, Wed., 25 Feb. 0.0305 0.0259 0.0282
01:01-02:00, Wed., 25 Feb. 0.0310 0.0262 0.0281
00:01-01:00, Wed., 25 Feb. 0.0299 0.0263 0.0282
23:01-24:00, Tue., 24 Feb. 0.0300 0.0263 0.0281
22:01-23:00, Tue., 24 Feb. 0.0302 0.0257 0.0280