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
14:01-15:00, Wed., 21 Jan. 0.0308 0.0261 0.0280
13:01-14:00, Wed., 21 Jan. 0.0299 0.0268 0.0284
12:01-13:00, Wed., 21 Jan. 0.0318 0.0263 0.0287
11:01-12:00, Wed., 21 Jan. 0.0307 0.0264 0.0286
10:01-11:00, Wed., 21 Jan. 0.0311 0.0263 0.0285
09:01-10:00, Wed., 21 Jan. 0.0310 0.0265 0.0286
08:01-09:00, Wed., 21 Jan. 0.0310 0.0272 0.0288
07:01-08:00, Wed., 21 Jan. 0.0320 0.0262 0.0289
06:01-07:00, Wed., 21 Jan. 0.0306 0.0266 0.0287
05:01-06:00, Wed., 21 Jan. 0.0310 0.0270 0.0287
04:01-05:00, Wed., 21 Jan. 0.0324 0.0267 0.0289
03:01-04:00, Wed., 21 Jan. 0.0309 0.0266 0.0286
02:01-03:00, Wed., 21 Jan. 0.0311 0.0264 0.0288
01:01-02:00, Wed., 21 Jan. 0.0304 0.0263 0.0285
00:01-01:00, Wed., 21 Jan. 0.0299 0.0263 0.0285
23:01-24:00, Tue., 20 Jan. 0.0308 0.0265 0.0286
22:01-23:00, Tue., 20 Jan. 0.0305 0.0266 0.0284
21:01-22:00, Tue., 20 Jan. 0.0311 0.0270 0.0288
20:01-21:00, Tue., 20 Jan. 0.0306 0.0267 0.0286
19:01-20:00, Tue., 20 Jan. 0.0304 0.0265 0.0283
18:01-19:00, Tue., 20 Jan. 0.0299 0.0260 0.0282
17:01-18:00, Tue., 20 Jan. 0.0300 0.0262 0.0285
16:01-17:00, Tue., 20 Jan. 0.0308 0.0262 0.0283
15:01-16:00, Tue., 20 Jan. 0.0304 0.0265 0.0285
14:01-15:00, Tue., 20 Jan. 0.0310 0.0269 0.0286
13:01-14:00, Tue., 20 Jan. 0.0307 0.0265 0.0286
12:01-13:00, Tue., 20 Jan. 0.0304 0.0264 0.0288
11:01-12:00, Tue., 20 Jan. 0.0307 0.0272 0.0289
10:01-11:00, Tue., 20 Jan. 0.0319 0.0266 0.0290
09:01-10:00, Tue., 20 Jan. 0.0308 0.0267 0.0287
08:01-09:00, Tue., 20 Jan. 0.0314 0.0265 0.0286
07:01-08:00, Tue., 20 Jan. 0.0303 0.0268 0.0287
06:01-07:00, Tue., 20 Jan. 0.0310 0.0267 0.0288
05:01-06:00, Tue., 20 Jan. 0.0339 0.0281 0.0304
04:01-05:00, Tue., 20 Jan. 0.0331 0.0287 0.0310
03:01-04:00, Tue., 20 Jan. 0.0346 0.0281 0.0303
02:01-03:00, Tue., 20 Jan. 0.0324 0.0277 0.0300
01:01-02:00, Tue., 20 Jan. 0.0312 0.0276 0.0295
00:01-01:00, Tue., 20 Jan. 0.0317 0.0278 0.0294
23:01-24:00, Mon., 19 Jan. 0.0313 0.0271 0.0292
22:01-23:00, Mon., 19 Jan. 0.0317 0.0252 0.0290
21:01-22:00, Mon., 19 Jan. 0.0314 0.0266 0.0290
20:01-21:00, Mon., 19 Jan. 0.0305 0.0267 0.0289
19:01-20:00, Mon., 19 Jan. 0.0310 0.0262 0.0285
18:01-19:00, Mon., 19 Jan. 0.0300 0.0264 0.0283
17:01-18:00, Mon., 19 Jan. 0.0301 0.0256 0.0280
16:01-17:00, Mon., 19 Jan. 0.0299 0.0262 0.0281
15:01-16:00, Mon., 19 Jan. 0.0303 0.0267 0.0285
14:01-15:00, Mon., 19 Jan. 0.0301 0.0257 0.0284
13:01-14:00, Mon., 19 Jan. 0.0308 0.0267 0.0284
12:01-13:00, Mon., 19 Jan. 0.0304 0.0263 0.0284
11:01-12:00, Mon., 19 Jan. 0.0309 0.0268 0.0287
10:01-11:00, Mon., 19 Jan. 0.0309 0.0265 0.0286
09:01-10:00, Mon., 19 Jan. 0.0308 0.0266 0.0286
08:01-09:00, Mon., 19 Jan. 0.0304 0.0257 0.0285
07:01-08:00, Mon., 19 Jan. 0.0306 0.0260 0.0284
06:01-07:00, Mon., 19 Jan. 0.0310 0.0263 0.0287
05:01-06:00, Mon., 19 Jan. 0.0314 0.0266 0.0286
04:01-05:00, Mon., 19 Jan. 0.0303 0.0261 0.0285
03:01-04:00, Mon., 19 Jan. 0.0305 0.0262 0.0286
02:01-03:00, Mon., 19 Jan. 0.0304 0.0257 0.0284
01:01-02:00, Mon., 19 Jan. 0.0303 0.0253 0.0281
00:01-01:00, Mon., 19 Jan. 0.0302 0.0262 0.0282
23:01-24:00, Sun., 18 Jan. 0.0297 0.0262 0.0280
22:01-23:00, Sun., 18 Jan. 0.0304 0.0258 0.0281
21:01-22:00, Sun., 18 Jan. 0.0298 0.0265 0.0282
20:01-21:00, Sun., 18 Jan. 0.0302 0.0263 0.0282
19:01-20:00, Sun., 18 Jan. 0.0311 0.0263 0.0282
18:01-19:00, Sun., 18 Jan. 0.0297 0.0258 0.0279
17:01-18:00, Sun., 18 Jan. 0.0301 0.0264 0.0283
16:01-17:00, Sun., 18 Jan. 0.0314 0.0264 0.0284
15:01-16:00, Sun., 18 Jan. 0.0310 0.0266 0.0286
14:01-15:00, Sun., 18 Jan. 0.0310 0.0263 0.0284
13:01-14:00, Sun., 18 Jan. 0.0305 0.0255 0.0284
12:01-13:00, Sun., 18 Jan. 0.0311 0.0273 0.0286
11:01-12:00, Sun., 18 Jan. 0.0308 0.0269 0.0285
10:01-11:00, Sun., 18 Jan. 0.0308 0.0264 0.0290
09:01-10:00, Sun., 18 Jan. 0.0322 0.0269 0.0287
08:01-09:00, Sun., 18 Jan. 0.0310 0.0266 0.0291
07:01-08:00, Sun., 18 Jan. 0.0315 0.0281 0.0298
06:01-07:00, Sun., 18 Jan. 0.0321 0.0270 0.0295
05:01-06:00, Sun., 18 Jan. 0.0305 0.0268 0.0286
04:01-05:00, Sun., 18 Jan. 0.0312 0.0271 0.0286
03:01-04:00, Sun., 18 Jan. 0.0302 0.0268 0.0283
02:01-03:00, Sun., 18 Jan. 0.0306 0.0266 0.0284
01:01-02:00, Sun., 18 Jan. 0.0305 0.0266 0.0284
00:01-01:00, Sun., 18 Jan. 0.0301 0.0256 0.0285
23:01-24:00, Sat., 17 Jan. 0.0307 0.0264 0.0286
22:01-23:00, Sat., 17 Jan. 0.0313 0.0268 0.0286
21:01-22:00, Sat., 17 Jan. 0.0306 0.0266 0.0286
20:01-21:00, Sat., 17 Jan. 0.0304 0.0270 0.0286
19:01-20:00, Sat., 17 Jan. 0.0304 0.0260 0.0285
18:01-19:00, Sat., 17 Jan. 0.0310 0.0259 0.0287
17:01-18:00, Sat., 17 Jan. 0.0304 0.0266 0.0287
16:01-17:00, Sat., 17 Jan. 0.0309 0.0266 0.0290
15:01-16:00, Sat., 17 Jan. 0.0315 0.0273 0.0294
14:01-15:00, Sat., 17 Jan. 0.0312 0.0272 0.0292
13:01-14:00, Sat., 17 Jan. 0.0322 0.0276 0.0295
12:01-13:00, Sat., 17 Jan. 0.0314 0.0264 0.0294
11:01-12:00, Sat., 17 Jan. 0.0318 0.0275 0.0294
10:01-11:00, Sat., 17 Jan. 0.0320 0.0276 0.0299
09:01-10:00, Sat., 17 Jan. 0.0323 0.0278 0.0303
08:01-09:00, Sat., 17 Jan. 0.0322 0.0280 0.0303
07:01-08:00, Sat., 17 Jan. 0.0329 0.0283 0.0303
06:01-07:00, Sat., 17 Jan. 0.0318 0.0283 0.0299
05:01-06:00, Sat., 17 Jan. 0.0325 0.0278 0.0304
04:01-05:00, Sat., 17 Jan. 0.0332 0.0281 0.0305
03:01-04:00, Sat., 17 Jan. 0.0316 0.0277 0.0298
02:01-03:00, Sat., 17 Jan. 0.0331 0.0280 0.0298
01:01-02:00, Sat., 17 Jan. 0.0311 0.0266 0.0294
00:01-01:00, Sat., 17 Jan. 0.0311 0.0270 0.0292
23:01-24:00, Fri., 16 Jan. 0.0308 0.0262 0.0288
22:01-23:00, Fri., 16 Jan. 0.0302 0.0253 0.0285
21:01-22:00, Fri., 16 Jan. 0.0304 0.0259 0.0279
20:01-21:00, Fri., 16 Jan. 0.0300 0.0257 0.0279
19:01-20:00, Fri., 16 Jan. 0.0299 0.0259 0.0280
18:01-19:00, Fri., 16 Jan. 0.0299 0.0260 0.0280
17:01-18:00, Fri., 16 Jan. 0.0318 0.0260 0.0282
16:01-17:00, Fri., 16 Jan. 0.0313 0.0264 0.0281
15:01-16:00, Fri., 16 Jan. 0.0305 0.0260 0.0286
14:01-15:00, Fri., 16 Jan. 0.0317 0.0268 0.0287
13:01-14:00, Fri., 16 Jan. 0.0306 0.0269 0.0288
12:01-13:00, Fri., 16 Jan. 0.0310 0.0268 0.0293
11:01-12:00, Fri., 16 Jan. 0.0315 0.0265 0.0293
10:01-11:00, Fri., 16 Jan. 0.0305 0.0260 0.0289
09:01-10:00, Fri., 16 Jan. 0.0318 0.0274 0.0298
08:01-09:00, Fri., 16 Jan. 0.0319 0.0277 0.0298
07:01-08:00, Fri., 16 Jan. 0.0313 0.0274 0.0297
06:01-07:00, Fri., 16 Jan. 0.0317 0.0274 0.0293
05:01-06:00, Fri., 16 Jan. 0.0327 0.0264 0.0294
04:01-05:00, Fri., 16 Jan. 0.0322 0.0264 0.0292
03:01-04:00, Fri., 16 Jan. 0.0310 0.0264 0.0287
02:01-03:00, Fri., 16 Jan. 0.0311 0.0263 0.0285
01:01-02:00, Fri., 16 Jan. 0.0311 0.0270 0.0287
00:01-01:00, Fri., 16 Jan. 0.0313 0.0266 0.0288
23:01-24:00, Thu., 15 Jan. 0.0312 0.0266 0.0289
22:01-23:00, Thu., 15 Jan. 0.0313 0.0267 0.0291
21:01-22:00, Thu., 15 Jan. 0.0310 0.0265 0.0285
20:01-21:00, Thu., 15 Jan. 0.0310 0.0263 0.0285
19:01-20:00, Thu., 15 Jan. 0.0310 0.0265 0.0284
18:01-19:00, Thu., 15 Jan. 0.0303 0.0267 0.0285
17:01-18:00, Thu., 15 Jan. 0.0308 0.0259 0.0282
16:01-17:00, Thu., 15 Jan. 0.0309 0.0262 0.0284
15:01-16:00, Thu., 15 Jan. 0.0299 0.0261 0.0282
14:01-15:00, Thu., 15 Jan. 0.0304 0.0254 0.0281
13:01-14:00, Thu., 15 Jan. 0.0311 0.0265 0.0284
12:01-13:00, Thu., 15 Jan. 0.0302 0.0266 0.0284
11:01-12:00, Thu., 15 Jan. 0.0308 0.0266 0.0288
10:01-11:00, Thu., 15 Jan. 0.0322 0.0268 0.0296
09:01-10:00, Thu., 15 Jan. 0.0328 0.0283 0.0301
08:01-09:00, Thu., 15 Jan. 0.0325 0.0283 0.0306
07:01-08:00, Thu., 15 Jan. 0.0334 0.0294 0.0312
06:01-07:00, Thu., 15 Jan. 0.0334 0.0294 0.0313
05:01-06:00, Thu., 15 Jan. 0.0325 0.0290 0.0307
04:01-05:00, Thu., 15 Jan. 0.0325 0.0283 0.0306
03:01-04:00, Thu., 15 Jan. 0.0327 0.0290 0.0307
02:01-03:00, Thu., 15 Jan. 0.0322 0.0274 0.0302
01:01-02:00, Thu., 15 Jan. 0.0327 0.0273 0.0299
00:01-01:00, Thu., 15 Jan. 0.0322 0.0272 0.0297
23:01-24:00, Wed., 14 Jan. 0.0311 0.0261 0.0297
22:01-23:00, Wed., 14 Jan. 0.0314 0.0266 0.0287
21:01-22:00, Wed., 14 Jan. 0.0301 0.0262 0.0283
20:01-21:00, Wed., 14 Jan. 0.0301 0.0259 0.0279
19:01-20:00, Wed., 14 Jan. 0.0302 0.0259 0.0279
18:01-19:00, Wed., 14 Jan. 0.0297 0.0262 0.0279
17:01-18:00, Wed., 14 Jan. 0.0308 0.0263 0.0281
16:01-17:00, Wed., 14 Jan. 0.0299 0.0259 0.0280
15:01-16:00, Wed., 14 Jan. 0.0305 0.0263 0.0283
14:01-15:00, Wed., 14 Jan. 0.0310 0.0263 0.0282
13:01-14:00, Wed., 14 Jan. 0.0301 0.0256 0.0282
12:01-13:00, Wed., 14 Jan. 0.0315 0.0266 0.0282
11:01-12:00, Wed., 14 Jan. 0.0298 0.0260 0.0278
10:01-11:00, Wed., 14 Jan. 0.0299 0.0256 0.0282
09:01-10:00, Wed., 14 Jan. 0.0314 0.0270 0.0288
08:01-09:00, Wed., 14 Jan. 0.0311 0.0265 0.0290
07:01-08:00, Wed., 14 Jan. 0.0310 0.0270 0.0288
06:01-07:00, Wed., 14 Jan. 0.0307 0.0269 0.0287
05:01-06:00, Wed., 14 Jan. 0.0307 0.0259 0.0287
04:01-05:00, Wed., 14 Jan. 0.0307 0.0262 0.0285
03:01-04:00, Wed., 14 Jan. 0.0309 0.0263 0.0282
02:01-03:00, Wed., 14 Jan. 0.0304 0.0262 0.0283
01:01-02:00, Wed., 14 Jan. 0.0302 0.0265 0.0283
00:01-01:00, Wed., 14 Jan. 0.0299 0.0256 0.0279
23:01-24:00, Tue., 13 Jan. 0.0299 0.0254 0.0282
22:01-23:00, Tue., 13 Jan. 0.0303 0.0255 0.0279
21:01-22:00, Tue., 13 Jan. 0.0303 0.0262 0.0279
20:01-21:00, Tue., 13 Jan. 0.0312 0.0257 0.0278
19:01-20:00, Tue., 13 Jan. 0.0308 0.0261 0.0282
18:01-19:00, Tue., 13 Jan. 0.0303 0.0256 0.0281
17:01-18:00, Tue., 13 Jan. 0.0306 0.0259 0.0282
16:01-17:00, Tue., 13 Jan. 0.0304 0.0259 0.0286
15:01-16:00, Tue., 13 Jan. 0.0311 0.0266 0.0286
14:01-15:00, Tue., 13 Jan. 0.0314 0.0270 0.0289
13:01-14:00, Tue., 13 Jan. 0.0308 0.0270 0.0286
12:01-13:00, Tue., 13 Jan. 0.0314 0.0260 0.0288
11:01-12:00, Tue., 13 Jan. 0.0309 0.0259 0.0290
10:01-11:00, Tue., 13 Jan. 0.0310 0.0273 0.0291
09:01-10:00, Tue., 13 Jan. 0.0322 0.0286 0.0303
08:01-09:00, Tue., 13 Jan. 0.0329 0.0286 0.0309
07:01-08:00, Tue., 13 Jan. 0.0329 0.0282 0.0305
06:01-07:00, Tue., 13 Jan. 0.0332 0.0286 0.0309
05:01-06:00, Tue., 13 Jan. 0.0334 0.0290 0.0311
04:01-05:00, Tue., 13 Jan. 0.0332 0.0287 0.0308
03:01-04:00, Tue., 13 Jan. 0.0332 0.0279 0.0304
02:01-03:00, Tue., 13 Jan. 0.0317 0.0280 0.0302
01:01-02:00, Tue., 13 Jan. 0.0325 0.0286 0.0304
00:01-01:00, Tue., 13 Jan. 0.0336 0.0278 0.0301
23:01-24:00, Mon., 12 Jan. 0.0316 0.0273 0.0295
22:01-23:00, Mon., 12 Jan. 0.0310 0.0275 0.0292
21:01-22:00, Mon., 12 Jan. 0.0312 0.0273 0.0290
20:01-21:00, Mon., 12 Jan. 0.0303 0.0270 0.0285
19:01-20:00, Mon., 12 Jan. 0.0295 0.0252 0.0279
18:01-19:00, Mon., 12 Jan. 0.0316 0.0256 0.0279
17:01-18:00, Mon., 12 Jan. 0.0298 0.0254 0.0278
16:01-17:00, Mon., 12 Jan. 0.0300 0.0256 0.0277
15:01-16:00, Mon., 12 Jan. 0.0306 0.0263 0.0283
14:01-15:00, Mon., 12 Jan. 0.0308 0.0263 0.0283
13:01-14:00, Mon., 12 Jan. 0.0306 0.0265 0.0284
12:01-13:00, Mon., 12 Jan. 0.0301 0.0266 0.0284
11:01-12:00, Mon., 12 Jan. 0.0308 0.0266 0.0285
10:01-11:00, Mon., 12 Jan. 0.0307 0.0262 0.0284
09:01-10:00, Mon., 12 Jan. 0.0310 0.0266 0.0290
08:01-09:00, Mon., 12 Jan. 0.0308 0.0267 0.0286
07:01-08:00, Mon., 12 Jan. 0.0307 0.0265 0.0287
06:01-07:00, Mon., 12 Jan. 0.0308 0.0259 0.0285
05:01-06:00, Mon., 12 Jan. 0.0307 0.0266 0.0285
04:01-05:00, Mon., 12 Jan. 0.0301 0.0257 0.0284
03:01-04:00, Mon., 12 Jan. 0.0302 0.0269 0.0284
02:01-03:00, Mon., 12 Jan. 0.0301 0.0262 0.0285
01:01-02:00, Mon., 12 Jan. 0.0309 0.0267 0.0286
00:01-01:00, Mon., 12 Jan. 0.0298 0.0257 0.0284
23:01-24:00, Sun., 11 Jan. 0.0303 0.0262 0.0284
22:01-23:00, Sun., 11 Jan. 0.0304 0.0257 0.0282
21:01-22:00, Sun., 11 Jan. 0.0304 0.0266 0.0284
20:01-21:00, Sun., 11 Jan. 0.0306 0.0259 0.0283
19:01-20:00, Sun., 11 Jan. 0.0304 0.0266 0.0283
18:01-19:00, Sun., 11 Jan. 0.0300 0.0262 0.0284
17:01-18:00, Sun., 11 Jan. 0.0310 0.0265 0.0286
16:01-17:00, Sun., 11 Jan. 0.0305 0.0257 0.0284
15:01-16:00, Sun., 11 Jan. 0.0322 0.0262 0.0283