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
16:01-17:00, Mon., 18 Aug. 0.0298 0.0263 0.0280
15:01-16:00, Mon., 18 Aug. 0.0303 0.0265 0.0283
14:01-15:00, Mon., 18 Aug. 0.0302 0.0266 0.0283
13:01-14:00, Mon., 18 Aug. 0.0315 0.0263 0.0287
12:01-13:00, Mon., 18 Aug. 0.0306 0.0270 0.0286
11:01-12:00, Mon., 18 Aug. 0.0304 0.0262 0.0285
10:01-11:00, Mon., 18 Aug. 0.0313 0.0268 0.0288
09:01-10:00, Mon., 18 Aug. 0.0307 0.0270 0.0289
08:01-09:00, Mon., 18 Aug. 0.0311 0.0271 0.0290
07:01-08:00, Mon., 18 Aug. 0.0309 0.0273 0.0292
06:01-07:00, Mon., 18 Aug. 0.0313 0.0263 0.0288
05:01-06:00, Mon., 18 Aug. 0.0318 0.0263 0.0288
04:01-05:00, Mon., 18 Aug. 0.0314 0.0261 0.0285
03:01-04:00, Mon., 18 Aug. 0.0311 0.0270 0.0284
02:01-03:00, Mon., 18 Aug. 0.0303 0.0266 0.0283
01:01-02:00, Mon., 18 Aug. 0.0310 0.0256 0.0279
00:01-01:00, Mon., 18 Aug. 0.0304 0.0259 0.0278
23:01-24:00, Sun., 17 Aug. 0.0301 0.0259 0.0281
22:01-23:00, Sun., 17 Aug. 0.0311 0.0260 0.0281
21:01-22:00, Sun., 17 Aug. 0.0302 0.0256 0.0279
20:01-21:00, Sun., 17 Aug. 0.0304 0.0251 0.0279
19:01-20:00, Sun., 17 Aug. 0.0298 0.0255 0.0280
18:01-19:00, Sun., 17 Aug. 0.0298 0.0262 0.0279
17:01-18:00, Sun., 17 Aug. 0.0299 0.0262 0.0280
16:01-17:00, Sun., 17 Aug. 0.0301 0.0251 0.0279
15:01-16:00, Sun., 17 Aug. 0.0299 0.0255 0.0277
14:01-15:00, Sun., 17 Aug. 0.0314 0.0259 0.0276
13:01-14:00, Sun., 17 Aug. 0.0294 0.0256 0.0277
12:01-13:00, Sun., 17 Aug. 0.0309 0.0259 0.0278
11:01-12:00, Sun., 17 Aug. 0.0297 0.0252 0.0277
10:01-11:00, Sun., 17 Aug. 0.0304 0.0262 0.0278
09:01-10:00, Sun., 17 Aug. 0.0297 0.0254 0.0276
08:01-09:00, Sun., 17 Aug. 0.0293 0.0260 0.0275
07:01-08:00, Sun., 17 Aug. 0.0299 0.0249 0.0275
06:01-07:00, Sun., 17 Aug. 0.0297 0.0258 0.0277
05:01-06:00, Sun., 17 Aug. 0.0322 0.0277 0.0297
04:01-05:00, Sun., 17 Aug. 0.0303 0.0261 0.0282
03:01-04:00, Sun., 17 Aug. 0.0300 0.0252 0.0274
02:01-03:00, Sun., 17 Aug. 0.0304 0.0256 0.0275
01:01-02:00, Sun., 17 Aug. 0.0294 0.0248 0.0272
00:01-01:00, Sun., 17 Aug. 0.0296 0.0252 0.0270
23:01-24:00, Sat., 16 Aug. 0.0294 0.0249 0.0271
22:01-23:00, Sat., 16 Aug. 0.0293 0.0259 0.0274
21:01-22:00, Sat., 16 Aug. 0.0303 0.0251 0.0277
20:01-21:00, Sat., 16 Aug. 0.0290 0.0251 0.0274
19:01-20:00, Sat., 16 Aug. 0.0298 0.0255 0.0273
18:01-19:00, Sat., 16 Aug. 0.0295 0.0248 0.0275
17:01-18:00, Sat., 16 Aug. 0.0293 0.0239 0.0273
16:01-17:00, Sat., 16 Aug. 0.0301 0.0254 0.0275
15:01-16:00, Sat., 16 Aug. 0.0297 0.0256 0.0274
14:01-15:00, Sat., 16 Aug. 0.0292 0.0256 0.0275
13:01-14:00, Sat., 16 Aug. 0.0292 0.0252 0.0274
12:01-13:00, Sat., 16 Aug. 0.0301 0.0260 0.0278
11:01-12:00, Sat., 16 Aug. 0.0302 0.0254 0.0275
10:01-11:00, Sat., 16 Aug. 0.0301 0.0252 0.0276
09:01-10:00, Sat., 16 Aug. 0.0306 0.0259 0.0279
08:01-09:00, Sat., 16 Aug. 0.0299 0.0256 0.0279
07:01-08:00, Sat., 16 Aug. 0.0305 0.0259 0.0281
06:01-07:00, Sat., 16 Aug. 0.0304 0.0261 0.0280
05:01-06:00, Sat., 16 Aug. 0.0293 0.0257 0.0274
04:01-05:00, Sat., 16 Aug. 0.0289 0.0249 0.0271
03:01-04:00, Sat., 16 Aug. 0.0297 0.0250 0.0272
02:01-03:00, Sat., 16 Aug. 0.0295 0.0255 0.0272
01:01-02:00, Sat., 16 Aug. 0.0293 0.0253 0.0273
00:01-01:00, Sat., 16 Aug. 0.0294 0.0256 0.0272
23:01-24:00, Fri., 15 Aug. 0.0298 0.0254 0.0274
22:01-23:00, Fri., 15 Aug. 0.0290 0.0257 0.0273
21:01-22:00, Fri., 15 Aug. 0.0296 0.0252 0.0271
20:01-21:00, Fri., 15 Aug. 0.0288 0.0256 0.0272
19:01-20:00, Fri., 15 Aug. 0.0298 0.0250 0.0275
18:01-19:00, Fri., 15 Aug. 0.0287 0.0256 0.0272
17:01-18:00, Fri., 15 Aug. 0.0294 0.0252 0.0271
16:01-17:00, Fri., 15 Aug. 0.0302 0.0248 0.0274
15:01-16:00, Fri., 15 Aug. 0.0297 0.0253 0.0272
14:01-15:00, Fri., 15 Aug. 0.0293 0.0256 0.0274
13:01-14:00, Fri., 15 Aug. 0.0300 0.0256 0.0275
12:01-13:00, Fri., 15 Aug. 0.0301 0.0252 0.0276
11:01-12:00, Fri., 15 Aug. 0.0301 0.0258 0.0276
10:01-11:00, Fri., 15 Aug. 0.0301 0.0254 0.0278
09:01-10:00, Fri., 15 Aug. 0.0297 0.0259 0.0277
08:01-09:00, Fri., 15 Aug. 0.0294 0.0256 0.0276
07:01-08:00, Fri., 15 Aug. 0.0291 0.0252 0.0273
06:01-07:00, Fri., 15 Aug. 0.0294 0.0252 0.0274
05:01-06:00, Fri., 15 Aug. 0.0293 0.0246 0.0276
04:01-05:00, Fri., 15 Aug. 0.0291 0.0254 0.0274
03:01-04:00, Fri., 15 Aug. 0.0288 0.0252 0.0273
02:01-03:00, Fri., 15 Aug. 0.0294 0.0252 0.0274
01:01-02:00, Fri., 15 Aug. 0.0292 0.0245 0.0269
00:01-01:00, Fri., 15 Aug. 0.0289 0.0252 0.0270
23:01-24:00, Thu., 14 Aug. 0.0302 0.0251 0.0269
22:01-23:00, Thu., 14 Aug. 0.0287 0.0253 0.0270
21:01-22:00, Thu., 14 Aug. 0.0290 0.0251 0.0269
20:01-21:00, Thu., 14 Aug. 0.0283 0.0246 0.0265
19:01-20:00, Thu., 14 Aug. 0.0295 0.0241 0.0270
18:01-19:00, Thu., 14 Aug. 0.0290 0.0249 0.0271
17:01-18:00, Thu., 14 Aug. 0.0294 0.0249 0.0270
16:01-17:00, Thu., 14 Aug. 0.0297 0.0249 0.0274
15:01-16:00, Thu., 14 Aug. 0.0289 0.0252 0.0272
14:01-15:00, Thu., 14 Aug. 0.0294 0.0257 0.0273
13:01-14:00, Thu., 14 Aug. 0.0295 0.0247 0.0271
12:01-13:00, Thu., 14 Aug. 0.0290 0.0251 0.0271
11:01-12:00, Thu., 14 Aug. 0.0294 0.0252 0.0272
10:01-11:00, Thu., 14 Aug. 0.0290 0.0252 0.0269
09:01-10:00, Thu., 14 Aug. 0.0290 0.0249 0.0271
08:01-09:00, Thu., 14 Aug. 0.0297 0.0249 0.0273
07:01-08:00, Thu., 14 Aug. 0.0287 0.0249 0.0271
06:01-07:00, Thu., 14 Aug. 0.0297 0.0259 0.0275
05:01-06:00, Thu., 14 Aug. 0.0294 0.0246 0.0271
04:01-05:00, Thu., 14 Aug. 0.0294 0.0250 0.0271
03:01-04:00, Thu., 14 Aug. 0.0290 0.0252 0.0271
02:01-03:00, Thu., 14 Aug. 0.0293 0.0243 0.0270
01:01-02:00, Thu., 14 Aug. 0.0292 0.0255 0.0273
00:01-01:00, Thu., 14 Aug. 0.0294 0.0251 0.0274
23:01-24:00, Wed., 13 Aug. 0.0294 0.0249 0.0270
22:01-23:00, Wed., 13 Aug. 0.0290 0.0249 0.0270
21:01-22:00, Wed., 13 Aug. 0.0295 0.0245 0.0274
20:01-21:00, Wed., 13 Aug. 0.0294 0.0260 0.0275
19:01-20:00, Wed., 13 Aug. 0.0295 0.0262 0.0274
18:01-19:00, Wed., 13 Aug. 0.0300 0.0251 0.0271
17:01-18:00, Wed., 13 Aug. 0.0294 0.0254 0.0272
16:01-17:00, Wed., 13 Aug. 0.0295 0.0254 0.0273
15:01-16:00, Wed., 13 Aug. 0.0298 0.0254 0.0272
14:01-15:00, Wed., 13 Aug. 0.0292 0.0242 0.0273
13:01-14:00, Wed., 13 Aug. 0.0296 0.0250 0.0273
12:01-13:00, Wed., 13 Aug. 0.0289 0.0245 0.0271
11:01-12:00, Wed., 13 Aug. 0.0298 0.0255 0.0273
10:01-11:00, Wed., 13 Aug. 0.0296 0.0249 0.0272
09:01-10:00, Wed., 13 Aug. 0.0288 0.0256 0.0272
08:01-09:00, Wed., 13 Aug. 0.0287 0.0248 0.0269
07:01-08:00, Wed., 13 Aug. 0.0300 0.0251 0.0272
06:01-07:00, Wed., 13 Aug. 0.0297 0.0255 0.0272
05:01-06:00, Wed., 13 Aug. 0.0294 0.0253 0.0274
04:01-05:00, Wed., 13 Aug. 0.0293 0.0238 0.0273
03:01-04:00, Wed., 13 Aug. 0.0298 0.0254 0.0273
02:01-03:00, Wed., 13 Aug. 0.0293 0.0256 0.0275
01:01-02:00, Wed., 13 Aug. 0.0298 0.0258 0.0278
00:01-01:00, Wed., 13 Aug. 0.0306 0.0262 0.0280
23:01-24:00, Tue., 12 Aug. 0.0303 0.0257 0.0281
22:01-23:00, Tue., 12 Aug. 0.0308 0.0257 0.0285
21:01-22:00, Tue., 12 Aug. 0.0346 0.0292 0.0317
20:01-21:00, Tue., 12 Aug. 0.0421 0.0325 0.0375
19:01-20:00, Tue., 12 Aug. 0.0423 0.0370 0.0393
18:01-19:00, Tue., 12 Aug. 0.0413 0.0339 0.0383
17:01-18:00, Tue., 12 Aug. 0.0368 0.0276 0.0326
16:01-17:00, Tue., 12 Aug. 0.0302 0.0269 0.0284
15:01-16:00, Tue., 12 Aug. 0.0308 0.0257 0.0279
14:01-15:00, Tue., 12 Aug. 0.0315 0.0267 0.0295
13:01-14:00, Tue., 12 Aug. 0.0352 0.0295 0.0322
12:01-13:00, Tue., 12 Aug. 0.0353 0.0270 0.0304
11:01-12:00, Tue., 12 Aug. 0.0294 0.0247 0.0270
10:01-11:00, Tue., 12 Aug. 0.0286 0.0251 0.0268
09:01-10:00, Tue., 12 Aug. 0.0285 0.0249 0.0267
08:01-09:00, Tue., 12 Aug. 0.0297 0.0245 0.0267
07:01-08:00, Tue., 12 Aug. 0.0284 0.0240 0.0263
06:01-07:00, Tue., 12 Aug. 0.0290 0.0244 0.0267
05:01-06:00, Tue., 12 Aug. 0.0292 0.0240 0.0262
04:01-05:00, Tue., 12 Aug. 0.0286 0.0243 0.0265
03:01-04:00, Tue., 12 Aug. 0.0289 0.0248 0.0267
02:01-03:00, Tue., 12 Aug. 0.0305 0.0252 0.0272
01:01-02:00, Tue., 12 Aug. 0.0288 0.0242 0.0266
00:01-01:00, Tue., 12 Aug. 0.0280 0.0235 0.0264
23:01-24:00, Mon., 11 Aug. 0.0287 0.0234 0.0262
22:01-23:00, Mon., 11 Aug. 0.0276 0.0236 0.0262
21:01-22:00, Mon., 11 Aug. 0.0278 0.0250 0.0264
20:01-21:00, Mon., 11 Aug. 0.0280 0.0249 0.0262
19:01-20:00, Mon., 11 Aug. 0.0294 0.0249 0.0269
18:01-19:00, Mon., 11 Aug. 0.0297 0.0261 0.0279
17:01-18:00, Mon., 11 Aug. 0.0361 0.0280 0.0324
16:01-17:00, Mon., 11 Aug. 0.0368 0.0278 0.0322
15:01-16:00, Mon., 11 Aug. 0.0345 0.0274 0.0304
14:01-15:00, Mon., 11 Aug. 0.0359 0.0271 0.0320
13:01-14:00, Mon., 11 Aug. 0.0339 0.0276 0.0307
12:01-13:00, Mon., 11 Aug. 0.0312 0.0248 0.0283
11:01-12:00, Mon., 11 Aug. 0.0326 0.0252 0.0292
10:01-11:00, Mon., 11 Aug. 0.0369 0.0297 0.0337
09:01-10:00, Mon., 11 Aug. 0.0379 0.0325 0.0352
08:01-09:00, Mon., 11 Aug. 0.0343 0.0244 0.0284
07:01-08:00, Mon., 11 Aug. 0.0286 0.0240 0.0265
06:01-07:00, Mon., 11 Aug. 0.0284 0.0246 0.0266
05:01-06:00, Mon., 11 Aug. 0.0296 0.0244 0.0267
04:01-05:00, Mon., 11 Aug. 0.0307 0.0259 0.0283
03:01-04:00, Mon., 11 Aug. 0.0327 0.0285 0.0305
02:01-03:00, Mon., 11 Aug. 0.0377 0.0298 0.0347
01:01-02:00, Mon., 11 Aug. 0.0455 0.0344 0.0391
00:01-01:00, Mon., 11 Aug. 0.0471 0.0411 0.0444
23:01-24:00, Sun., 10 Aug. 0.0468 0.0377 0.0417
22:01-23:00, Sun., 10 Aug. 0.0409 0.0353 0.0383
21:01-22:00, Sun., 10 Aug. 0.0418 0.0349 0.0384
20:01-21:00, Sun., 10 Aug. 0.0395 0.0336 0.0370
19:01-20:00, Sun., 10 Aug. 0.0392 0.0322 0.0351
18:01-19:00, Sun., 10 Aug. 0.0325 0.0284 0.0302
17:01-18:00, Sun., 10 Aug. 0.0326 0.0273 0.0305
16:01-17:00, Sun., 10 Aug. 0.0316 0.0279 0.0297
15:01-16:00, Sun., 10 Aug. 0.0322 0.0278 0.0300
14:01-15:00, Sun., 10 Aug. 0.0330 0.0283 0.0301
13:01-14:00, Sun., 10 Aug. 0.0336 0.0285 0.0315
12:01-13:00, Sun., 10 Aug. 0.0336 0.0297 0.0315
11:01-12:00, Sun., 10 Aug. 0.0338 0.0286 0.0307
10:01-11:00, Sun., 10 Aug. 0.0376 0.0301 0.0337
09:01-10:00, Sun., 10 Aug. 0.0423 0.0346 0.0380
08:01-09:00, Sun., 10 Aug. 0.0423 0.0367 0.0397
07:01-08:00, Sun., 10 Aug. 0.0398 0.0284 0.0327
06:01-07:00, Sun., 10 Aug. 0.0330 0.0286 0.0302
05:01-06:00, Sun., 10 Aug. 0.0336 0.0281 0.0309
04:01-05:00, Sun., 10 Aug. 0.0340 0.0290 0.0316
03:01-04:00, Sun., 10 Aug. 0.0355 0.0312 0.0330
02:01-03:00, Sun., 10 Aug. 0.0367 0.0273 0.0321
01:01-02:00, Sun., 10 Aug. 0.0323 0.0271 0.0290
00:01-01:00, Sun., 10 Aug. 0.0316 0.0265 0.0293
23:01-24:00, Sat., 09 Aug. 0.0311 0.0274 0.0290
22:01-23:00, Sat., 09 Aug. 0.0315 0.0270 0.0290
21:01-22:00, Sat., 09 Aug. 0.0311 0.0269 0.0290
20:01-21:00, Sat., 09 Aug. 0.0326 0.0259 0.0292
19:01-20:00, Sat., 09 Aug. 0.0318 0.0258 0.0293
18:01-19:00, Sat., 09 Aug. 0.0312 0.0262 0.0291
17:01-18:00, Sat., 09 Aug. 0.0318 0.0272 0.0293
16:01-17:00, Sat., 09 Aug. 0.0313 0.0260 0.0290
15:01-16:00, Sat., 09 Aug. 0.0310 0.0268 0.0292
14:01-15:00, Sat., 09 Aug. 0.0311 0.0270 0.0293
13:01-14:00, Sat., 09 Aug. 0.0310 0.0273 0.0294
12:01-13:00, Sat., 09 Aug. 0.0310 0.0275 0.0292
11:01-12:00, Sat., 09 Aug. 0.0313 0.0268 0.0289
10:01-11:00, Sat., 09 Aug. 0.0312 0.0274 0.0293
09:01-10:00, Sat., 09 Aug. 0.0324 0.0279 0.0298
08:01-09:00, Sat., 09 Aug. 0.0325 0.0276 0.0296
07:01-08:00, Sat., 09 Aug. 0.0319 0.0274 0.0298
06:01-07:00, Sat., 09 Aug. 0.0315 0.0276 0.0297
05:01-06:00, Sat., 09 Aug. 0.0318 0.0276 0.0296
04:01-05:00, Sat., 09 Aug. 0.0329 0.0270 0.0295
03:01-04:00, Sat., 09 Aug. 0.0315 0.0273 0.0294
02:01-03:00, Sat., 09 Aug. 0.0317 0.0267 0.0296
01:01-02:00, Sat., 09 Aug. 0.0322 0.0270 0.0292
00:01-01:00, Sat., 09 Aug. 0.0308 0.0271 0.0293
23:01-24:00, Fri., 08 Aug. 0.0316 0.0276 0.0294
22:01-23:00, Fri., 08 Aug. 0.0316 0.0270 0.0290
21:01-22:00, Fri., 08 Aug. 0.0313 0.0266 0.0293
20:01-21:00, Fri., 08 Aug. 0.0336 0.0273 0.0294
19:01-20:00, Fri., 08 Aug. 0.0315 0.0273 0.0293
18:01-19:00, Fri., 08 Aug. 0.0313 0.0277 0.0294
17:01-18:00, Fri., 08 Aug. 0.0318 0.0273 0.0298