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
11:01-12:00, Sun., 22 Dec. 0.0300 0.0269 0.0282
10:01-11:00, Sun., 22 Dec. 0.0303 0.0262 0.0280
09:01-10:00, Sun., 22 Dec. 0.0298 0.0263 0.0282
08:01-09:00, Sun., 22 Dec. 0.0304 0.0263 0.0282
07:01-08:00, Sun., 22 Dec. 0.0297 0.0266 0.0281
06:01-07:00, Sun., 22 Dec. 0.0308 0.0257 0.0284
05:01-06:00, Sun., 22 Dec. 0.0308 0.0270 0.0287
04:01-05:00, Sun., 22 Dec. 0.0318 0.0263 0.0288
03:01-04:00, Sun., 22 Dec. 0.0310 0.0262 0.0289
02:01-03:00, Sun., 22 Dec. 0.0310 0.0273 0.0292
01:01-02:00, Sun., 22 Dec. 0.0313 0.0271 0.0290
00:01-01:00, Sun., 22 Dec. 0.0304 0.0263 0.0286
23:01-24:00, Sat., 21 Dec. 0.0307 0.0264 0.0284
22:01-23:00, Sat., 21 Dec. 0.0293 0.0251 0.0275
21:01-22:00, Sat., 21 Dec. 0.0302 0.0258 0.0278
20:01-21:00, Sat., 21 Dec. 0.0297 0.0255 0.0277
19:01-20:00, Sat., 21 Dec. 0.0301 0.0249 0.0276
18:01-19:00, Sat., 21 Dec. 0.0291 0.0253 0.0274
17:01-18:00, Sat., 21 Dec. 0.0293 0.0255 0.0274
16:01-17:00, Sat., 21 Dec. 0.0294 0.0259 0.0274
15:01-16:00, Sat., 21 Dec. 0.0301 0.0250 0.0277
14:01-15:00, Sat., 21 Dec. 0.0302 0.0259 0.0279
13:01-14:00, Sat., 21 Dec. 0.0301 0.0256 0.0278
12:01-13:00, Sat., 21 Dec. 0.0294 0.0252 0.0278
11:01-12:00, Sat., 21 Dec. 0.0296 0.0256 0.0278
10:01-11:00, Sat., 21 Dec. 0.0301 0.0262 0.0279
09:01-10:00, Sat., 21 Dec. 0.0304 0.0263 0.0288
08:01-09:00, Sat., 21 Dec. 0.0322 0.0266 0.0293
07:01-08:00, Sat., 21 Dec. 0.0328 0.0288 0.0304
06:01-07:00, Sat., 21 Dec. 0.0325 0.0284 0.0302
05:01-06:00, Sat., 21 Dec. 0.0333 0.0268 0.0300
04:01-05:00, Sat., 21 Dec. 0.0311 0.0264 0.0290
03:01-04:00, Sat., 21 Dec. 0.0310 0.0273 0.0291
02:01-03:00, Sat., 21 Dec. 0.0311 0.0273 0.0286
01:01-02:00, Sat., 21 Dec. 0.0311 0.0249 0.0282
00:01-01:00, Sat., 21 Dec. 0.0297 0.0267 0.0282
23:01-24:00, Fri., 20 Dec. 0.0302 0.0264 0.0284
22:01-23:00, Fri., 20 Dec. 0.0310 0.0266 0.0285
21:01-22:00, Fri., 20 Dec. 0.0308 0.0266 0.0287
20:01-21:00, Fri., 20 Dec. 0.0301 0.0266 0.0283
19:01-20:00, Fri., 20 Dec. 0.0296 0.0259 0.0277
18:01-19:00, Fri., 20 Dec. 0.0294 0.0252 0.0274
17:01-18:00, Fri., 20 Dec. 0.0292 0.0258 0.0271
16:01-17:00, Fri., 20 Dec. 0.0290 0.0256 0.0272
15:01-16:00, Fri., 20 Dec. 0.0287 0.0242 0.0270
14:01-15:00, Fri., 20 Dec. 0.0291 0.0252 0.0273
13:01-14:00, Fri., 20 Dec. 0.0291 0.0255 0.0276
12:01-13:00, Fri., 20 Dec. 0.0298 0.0258 0.0277
11:01-12:00, Fri., 20 Dec. 0.0302 0.0249 0.0278
10:01-11:00, Fri., 20 Dec. 0.0308 0.0254 0.0279
09:01-10:00, Fri., 20 Dec. 0.0307 0.0259 0.0284
08:01-09:00, Fri., 20 Dec. 0.0308 0.0259 0.0285
07:01-08:00, Fri., 20 Dec. 0.0304 0.0273 0.0289
06:01-07:00, Fri., 20 Dec. 0.0308 0.0266 0.0287
05:01-06:00, Fri., 20 Dec. 0.0300 0.0270 0.0286
04:01-05:00, Fri., 20 Dec. 0.0318 0.0268 0.0291
03:01-04:00, Fri., 20 Dec. 0.0315 0.0266 0.0288
02:01-03:00, Fri., 20 Dec. 0.0301 0.0258 0.0282
01:01-02:00, Fri., 20 Dec. 0.0301 0.0261 0.0280
00:01-01:00, Fri., 20 Dec. 0.0301 0.0257 0.0275
23:01-24:00, Thu., 19 Dec. 0.0292 0.0252 0.0274
22:01-23:00, Thu., 19 Dec. 0.0301 0.0257 0.0277
21:01-22:00, Thu., 19 Dec. 0.0291 0.0254 0.0273
20:01-21:00, Thu., 19 Dec. 0.0301 0.0255 0.0275
19:01-20:00, Thu., 19 Dec. 0.0294 0.0255 0.0273
18:01-19:00, Thu., 19 Dec. 0.0297 0.0248 0.0274
17:01-18:00, Thu., 19 Dec. 0.0292 0.0256 0.0274
16:01-17:00, Thu., 19 Dec. 0.0304 0.0260 0.0279
15:01-16:00, Thu., 19 Dec. 0.0293 0.0250 0.0278
14:01-15:00, Thu., 19 Dec. 0.0297 0.0256 0.0280
13:01-14:00, Thu., 19 Dec. 0.0294 0.0257 0.0279
12:01-13:00, Thu., 19 Dec. 0.0298 0.0258 0.0278
11:01-12:00, Thu., 19 Dec. 0.0301 0.0256 0.0278
10:01-11:00, Thu., 19 Dec. 0.0298 0.0263 0.0280
09:01-10:00, Thu., 19 Dec. 0.0307 0.0270 0.0285
08:01-09:00, Thu., 19 Dec. 0.0318 0.0275 0.0294
07:01-08:00, Thu., 19 Dec. 0.0322 0.0283 0.0302
06:01-07:00, Thu., 19 Dec. 0.0308 0.0266 0.0287
05:01-06:00, Thu., 19 Dec. 0.0315 0.0265 0.0289
04:01-05:00, Thu., 19 Dec. 0.0311 0.0267 0.0288
03:01-04:00, Thu., 19 Dec. 0.0324 0.0278 0.0301
02:01-03:00, Thu., 19 Dec. 0.0332 0.0273 0.0302
01:01-02:00, Thu., 19 Dec. 0.0309 0.0266 0.0287
00:01-01:00, Thu., 19 Dec. 0.0301 0.0258 0.0282
23:01-24:00, Wed., 18 Dec. 0.0297 0.0256 0.0278
22:01-23:00, Wed., 18 Dec. 0.0299 0.0259 0.0278
21:01-22:00, Wed., 18 Dec. 0.0307 0.0259 0.0279
20:01-21:00, Wed., 18 Dec. 0.0300 0.0253 0.0281
19:01-20:00, Wed., 18 Dec. 0.0305 0.0255 0.0278
18:01-19:00, Wed., 18 Dec. 0.0296 0.0256 0.0277
17:01-18:00, Wed., 18 Dec. 0.0303 0.0258 0.0277
16:01-17:00, Wed., 18 Dec. 0.0291 0.0260 0.0276
15:01-16:00, Wed., 18 Dec. 0.0304 0.0259 0.0281
14:01-15:00, Wed., 18 Dec. 0.0304 0.0262 0.0282
13:01-14:00, Wed., 18 Dec. 0.0309 0.0263 0.0281
12:01-13:00, Wed., 18 Dec. 0.0301 0.0259 0.0282
11:01-12:00, Wed., 18 Dec. 0.0306 0.0270 0.0287
10:01-11:00, Wed., 18 Dec. 0.0307 0.0263 0.0286
09:01-10:00, Wed., 18 Dec. 0.0318 0.0272 0.0292
08:01-09:00, Wed., 18 Dec. 0.0331 0.0274 0.0299
07:01-08:00, Wed., 18 Dec. 0.0321 0.0286 0.0302
06:01-07:00, Wed., 18 Dec. 0.0329 0.0287 0.0302
05:01-06:00, Wed., 18 Dec. 0.0324 0.0280 0.0303
04:01-05:00, Wed., 18 Dec. 0.0322 0.0285 0.0299
03:01-04:00, Wed., 18 Dec. 0.0319 0.0280 0.0301
02:01-03:00, Wed., 18 Dec. 0.0315 0.0274 0.0295
01:01-02:00, Wed., 18 Dec. 0.0325 0.0280 0.0297
00:01-01:00, Wed., 18 Dec. 0.0318 0.0276 0.0298
23:01-24:00, Tue., 17 Dec. 0.0315 0.0273 0.0294
22:01-23:00, Tue., 17 Dec. 0.0307 0.0275 0.0289
21:01-22:00, Tue., 17 Dec. 0.0310 0.0271 0.0288
20:01-21:00, Tue., 17 Dec. 0.0302 0.0268 0.0284
19:01-20:00, Tue., 17 Dec. 0.0297 0.0253 0.0278
18:01-19:00, Tue., 17 Dec. 0.0292 0.0256 0.0277
17:01-18:00, Tue., 17 Dec. 0.0297 0.0252 0.0276
16:01-17:00, Tue., 17 Dec. 0.0292 0.0255 0.0274
15:01-16:00, Tue., 17 Dec. 0.0297 0.0256 0.0277
14:01-15:00, Tue., 17 Dec. 0.0311 0.0262 0.0279
13:01-14:00, Tue., 17 Dec. 0.0310 0.0259 0.0284
12:01-13:00, Tue., 17 Dec. 0.0305 0.0252 0.0285
11:01-12:00, Tue., 17 Dec. 0.0319 0.0265 0.0285
10:01-11:00, Tue., 17 Dec. 0.0316 0.0261 0.0289
09:01-10:00, Tue., 17 Dec. 0.0328 0.0273 0.0298
08:01-09:00, Tue., 17 Dec. 0.0338 0.0280 0.0304
07:01-08:00, Tue., 17 Dec. 0.0325 0.0279 0.0303
06:01-07:00, Tue., 17 Dec. 0.0323 0.0285 0.0304
05:01-06:00, Tue., 17 Dec. 0.0329 0.0282 0.0305
04:01-05:00, Tue., 17 Dec. 0.0327 0.0280 0.0303
03:01-04:00, Tue., 17 Dec. 0.0322 0.0277 0.0300
02:01-03:00, Tue., 17 Dec. 0.0319 0.0283 0.0299
01:01-02:00, Tue., 17 Dec. 0.0311 0.0263 0.0292
00:01-01:00, Tue., 17 Dec. 0.0320 0.0271 0.0292
23:01-24:00, Mon., 16 Dec. 0.0309 0.0269 0.0291
22:01-23:00, Mon., 16 Dec. 0.0319 0.0273 0.0295
21:01-22:00, Mon., 16 Dec. 0.0310 0.0259 0.0291
20:01-21:00, Mon., 16 Dec. 0.0302 0.0262 0.0283
19:01-20:00, Mon., 16 Dec. 0.0300 0.0260 0.0280
18:01-19:00, Mon., 16 Dec. 0.0301 0.0256 0.0276
17:01-18:00, Mon., 16 Dec. 0.0307 0.0252 0.0277
16:01-17:00, Mon., 16 Dec. 0.0300 0.0254 0.0279
15:01-16:00, Mon., 16 Dec. 0.0304 0.0258 0.0281
14:01-15:00, Mon., 16 Dec. 0.0304 0.0263 0.0282
13:01-14:00, Mon., 16 Dec. 0.0301 0.0263 0.0283
12:01-13:00, Mon., 16 Dec. 0.0304 0.0267 0.0285
11:01-12:00, Mon., 16 Dec. 0.0306 0.0267 0.0285
10:01-11:00, Mon., 16 Dec. 0.0305 0.0264 0.0286
09:01-10:00, Mon., 16 Dec. 0.0311 0.0276 0.0292
08:01-09:00, Mon., 16 Dec. 0.0315 0.0276 0.0298
07:01-08:00, Mon., 16 Dec. 0.0324 0.0276 0.0300
06:01-07:00, Mon., 16 Dec. 0.0326 0.0280 0.0301
05:01-06:00, Mon., 16 Dec. 0.0324 0.0278 0.0301
04:01-05:00, Mon., 16 Dec. 0.0319 0.0274 0.0298
03:01-04:00, Mon., 16 Dec. 0.0315 0.0275 0.0298
02:01-03:00, Mon., 16 Dec. 0.0317 0.0273 0.0294
01:01-02:00, Mon., 16 Dec. 0.0311 0.0273 0.0292
00:01-01:00, Mon., 16 Dec. 0.0297 0.0261 0.0282
23:01-24:00, Sun., 15 Dec. 0.0297 0.0258 0.0281
22:01-23:00, Sun., 15 Dec. 0.0306 0.0252 0.0279
21:01-22:00, Sun., 15 Dec. 0.0297 0.0249 0.0277
20:01-21:00, Sun., 15 Dec. 0.0294 0.0258 0.0276
19:01-20:00, Sun., 15 Dec. 0.0295 0.0262 0.0277
18:01-19:00, Sun., 15 Dec. 0.0301 0.0252 0.0280
17:01-18:00, Sun., 15 Dec. 0.0299 0.0257 0.0277
16:01-17:00, Sun., 15 Dec. 0.0288 0.0252 0.0274
15:01-16:00, Sun., 15 Dec. 0.0296 0.0253 0.0276
14:01-15:00, Sun., 15 Dec. 0.0297 0.0249 0.0278
13:01-14:00, Sun., 15 Dec. 0.0302 0.0256 0.0277
12:01-13:00, Sun., 15 Dec. 0.0301 0.0260 0.0280
11:01-12:00, Sun., 15 Dec. 0.0303 0.0255 0.0278
10:01-11:00, Sun., 15 Dec. 0.0305 0.0262 0.0281
09:01-10:00, Sun., 15 Dec. 0.0306 0.0262 0.0287
08:01-09:00, Sun., 15 Dec. 0.0312 0.0276 0.0295
07:01-08:00, Sun., 15 Dec. 0.0342 0.0274 0.0299
06:01-07:00, Sun., 15 Dec. 0.0317 0.0275 0.0297
05:01-06:00, Sun., 15 Dec. 0.0328 0.0276 0.0299
04:01-05:00, Sun., 15 Dec. 0.0321 0.0266 0.0295
03:01-04:00, Sun., 15 Dec. 0.0308 0.0263 0.0290
02:01-03:00, Sun., 15 Dec. 0.0315 0.0273 0.0290
01:01-02:00, Sun., 15 Dec. 0.0309 0.0261 0.0283
00:01-01:00, Sun., 15 Dec. 0.0302 0.0261 0.0282
23:01-24:00, Sat., 14 Dec. 0.0301 0.0259 0.0279
22:01-23:00, Sat., 14 Dec. 0.0294 0.0249 0.0275
21:01-22:00, Sat., 14 Dec. 0.0297 0.0255 0.0273
20:01-21:00, Sat., 14 Dec. 0.0291 0.0252 0.0271
19:01-20:00, Sat., 14 Dec. 0.0296 0.0252 0.0271
18:01-19:00, Sat., 14 Dec. 0.0292 0.0252 0.0273
17:01-18:00, Sat., 14 Dec. 0.0303 0.0244 0.0274
16:01-17:00, Sat., 14 Dec. 0.0301 0.0245 0.0274
15:01-16:00, Sat., 14 Dec. 0.0301 0.0259 0.0277
14:01-15:00, Sat., 14 Dec. 0.0299 0.0250 0.0278
13:01-14:00, Sat., 14 Dec. 0.0294 0.0256 0.0278
12:01-13:00, Sat., 14 Dec. 0.0297 0.0260 0.0276
11:01-12:00, Sat., 14 Dec. 0.0300 0.0258 0.0277
10:01-11:00, Sat., 14 Dec. 0.0297 0.0255 0.0276
09:01-10:00, Sat., 14 Dec. 0.0296 0.0262 0.0277
08:01-09:00, Sat., 14 Dec. 0.0297 0.0261 0.0278
07:01-08:00, Sat., 14 Dec. 0.0299 0.0261 0.0280
06:01-07:00, Sat., 14 Dec. 0.0307 0.0271 0.0288
05:01-06:00, Sat., 14 Dec. 0.0315 0.0275 0.0294
04:01-05:00, Sat., 14 Dec. 0.0325 0.0273 0.0297
03:01-04:00, Sat., 14 Dec. 0.0319 0.0282 0.0302
02:01-03:00, Sat., 14 Dec. 0.0315 0.0278 0.0294
01:01-02:00, Sat., 14 Dec. 0.0312 0.0269 0.0293
00:01-01:00, Sat., 14 Dec. 0.0308 0.0270 0.0291
23:01-24:00, Fri., 13 Dec. 0.0307 0.0272 0.0291
22:01-23:00, Fri., 13 Dec. 0.0308 0.0254 0.0288
21:01-22:00, Fri., 13 Dec. 0.0310 0.0260 0.0285
20:01-21:00, Fri., 13 Dec. 0.0302 0.0259 0.0286
19:01-20:00, Fri., 13 Dec. 0.0297 0.0268 0.0284
18:01-19:00, Fri., 13 Dec. 0.0304 0.0264 0.0286
17:01-18:00, Fri., 13 Dec. 0.0304 0.0260 0.0284
16:01-17:00, Fri., 13 Dec. 0.0305 0.0267 0.0286
15:01-16:00, Fri., 13 Dec. 0.0304 0.0266 0.0286
14:01-15:00, Fri., 13 Dec. 0.0303 0.0270 0.0286
13:01-14:00, Fri., 13 Dec. 0.0302 0.0263 0.0284
12:01-13:00, Fri., 13 Dec. 0.0303 0.0262 0.0281
11:01-12:00, Fri., 13 Dec. 0.0301 0.0263 0.0283
10:01-11:00, Fri., 13 Dec. 0.0306 0.0261 0.0286
09:01-10:00, Fri., 13 Dec. 0.0313 0.0263 0.0288
08:01-09:00, Fri., 13 Dec. 0.0320 0.0276 0.0301
07:01-08:00, Fri., 13 Dec. 0.0325 0.0276 0.0299
06:01-07:00, Fri., 13 Dec. 0.0324 0.0270 0.0300
05:01-06:00, Fri., 13 Dec. 0.0321 0.0277 0.0297
04:01-05:00, Fri., 13 Dec. 0.0319 0.0275 0.0293
03:01-04:00, Fri., 13 Dec. 0.0311 0.0260 0.0285
02:01-03:00, Fri., 13 Dec. 0.0294 0.0259 0.0276
01:01-02:00, Fri., 13 Dec. 0.0296 0.0261 0.0278
00:01-01:00, Fri., 13 Dec. 0.0303 0.0252 0.0277
23:01-24:00, Thu., 12 Dec. 0.0291 0.0250 0.0274
22:01-23:00, Thu., 12 Dec. 0.0297 0.0256 0.0274
21:01-22:00, Thu., 12 Dec. 0.0292 0.0243 0.0271
20:01-21:00, Thu., 12 Dec. 0.0296 0.0248 0.0271
19:01-20:00, Thu., 12 Dec. 0.0295 0.0242 0.0271
18:01-19:00, Thu., 12 Dec. 0.0293 0.0256 0.0272
17:01-18:00, Thu., 12 Dec. 0.0294 0.0252 0.0271
16:01-17:00, Thu., 12 Dec. 0.0295 0.0252 0.0272
15:01-16:00, Thu., 12 Dec. 0.0293 0.0255 0.0272
14:01-15:00, Thu., 12 Dec. 0.0301 0.0253 0.0274
13:01-14:00, Thu., 12 Dec. 0.0295 0.0252 0.0274
12:01-13:00, Thu., 12 Dec. 0.0296 0.0262 0.0276