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
01:01-02:00, Fri., 21 Nov. 0.0309 0.0259 0.0288
00:01-01:00, Fri., 21 Nov. 0.0309 0.0262 0.0286
23:01-24:00, Thu., 20 Nov. 0.0311 0.0267 0.0287
22:01-23:00, Thu., 20 Nov. 0.0306 0.0262 0.0285
21:01-22:00, Thu., 20 Nov. 0.0301 0.0257 0.0281
20:01-21:00, Thu., 20 Nov. 0.0291 0.0258 0.0275
19:01-20:00, Thu., 20 Nov. 0.0297 0.0242 0.0273
18:01-19:00, Thu., 20 Nov. 0.0287 0.0249 0.0268
17:01-18:00, Thu., 20 Nov. 0.0289 0.0250 0.0270
16:01-17:00, Thu., 20 Nov. 0.0302 0.0248 0.0271
15:01-16:00, Thu., 20 Nov. 0.0290 0.0256 0.0274
14:01-15:00, Thu., 20 Nov. 0.0293 0.0252 0.0274
13:01-14:00, Thu., 20 Nov. 0.0292 0.0257 0.0276
12:01-13:00, Thu., 20 Nov. 0.0298 0.0256 0.0274
11:01-12:00, Thu., 20 Nov. 0.0301 0.0259 0.0278
10:01-11:00, Thu., 20 Nov. 0.0308 0.0268 0.0286
09:01-10:00, Thu., 20 Nov. 0.0315 0.0276 0.0293
08:01-09:00, Thu., 20 Nov. 0.0312 0.0276 0.0292
07:01-08:00, Thu., 20 Nov. 0.0317 0.0269 0.0287
06:01-07:00, Thu., 20 Nov. 0.0309 0.0266 0.0286
05:01-06:00, Thu., 20 Nov. 0.0310 0.0260 0.0286
04:01-05:00, Thu., 20 Nov. 0.0301 0.0259 0.0286
03:01-04:00, Thu., 20 Nov. 0.0307 0.0260 0.0283
02:01-03:00, Thu., 20 Nov. 0.0301 0.0251 0.0280
01:01-02:00, Thu., 20 Nov. 0.0294 0.0256 0.0277
00:01-01:00, Thu., 20 Nov. 0.0297 0.0258 0.0280
23:01-24:00, Wed., 19 Nov. 0.0296 0.0262 0.0279
22:01-23:00, Wed., 19 Nov. 0.0301 0.0259 0.0283
21:01-22:00, Wed., 19 Nov. 0.0304 0.0258 0.0280
20:01-21:00, Wed., 19 Nov. 0.0301 0.0249 0.0276
19:01-20:00, Wed., 19 Nov. 0.0294 0.0252 0.0274
18:01-19:00, Wed., 19 Nov. 0.0289 0.0245 0.0270
17:01-18:00, Wed., 19 Nov. 0.0290 0.0250 0.0270
16:01-17:00, Wed., 19 Nov. 0.0297 0.0249 0.0271
15:01-16:00, Wed., 19 Nov. 0.0293 0.0246 0.0273
14:01-15:00, Wed., 19 Nov. 0.0295 0.0256 0.0273
13:01-14:00, Wed., 19 Nov. 0.0286 0.0250 0.0270
12:01-13:00, Wed., 19 Nov. 0.0300 0.0253 0.0271
11:01-12:00, Wed., 19 Nov. 0.0303 0.0258 0.0274
10:01-11:00, Wed., 19 Nov. 0.0291 0.0256 0.0274
09:01-10:00, Wed., 19 Nov. 0.0299 0.0252 0.0272
08:01-09:00, Wed., 19 Nov. 0.0292 0.0250 0.0272
07:01-08:00, Wed., 19 Nov. 0.0297 0.0249 0.0270
06:01-07:00, Wed., 19 Nov. 0.0290 0.0249 0.0269
05:01-06:00, Wed., 19 Nov. 0.0292 0.0251 0.0271
04:01-05:00, Wed., 19 Nov. 0.0290 0.0252 0.0269
03:01-04:00, Wed., 19 Nov. 0.0290 0.0254 0.0271
02:01-03:00, Wed., 19 Nov. 0.0290 0.0254 0.0273
01:01-02:00, Wed., 19 Nov. 0.0292 0.0249 0.0270
00:01-01:00, Wed., 19 Nov. 0.0294 0.0249 0.0273
23:01-24:00, Tue., 18 Nov. 0.0292 0.0252 0.0274
22:01-23:00, Tue., 18 Nov. 0.0297 0.0256 0.0274
21:01-22:00, Tue., 18 Nov. 0.0305 0.0255 0.0280
20:01-21:00, Tue., 18 Nov. 0.0297 0.0256 0.0281
19:01-20:00, Tue., 18 Nov. 0.0348 0.0276 0.0306
18:01-19:00, Tue., 18 Nov. 0.0363 0.0297 0.0326
17:01-18:00, Tue., 18 Nov. 0.0335 0.0271 0.0303
16:01-17:00, Tue., 18 Nov. 0.0322 0.0263 0.0294
15:01-16:00, Tue., 18 Nov. 0.0298 0.0253 0.0279
14:01-15:00, Tue., 18 Nov. 0.0297 0.0259 0.0280
13:01-14:00, Tue., 18 Nov. 0.0303 0.0265 0.0283
12:01-13:00, Tue., 18 Nov. 0.0302 0.0262 0.0282
11:01-12:00, Tue., 18 Nov. 0.0301 0.0263 0.0280
10:01-11:00, Tue., 18 Nov. 0.0305 0.0258 0.0282
09:01-10:00, Tue., 18 Nov. 0.0303 0.0260 0.0281
08:01-09:00, Tue., 18 Nov. 0.0300 0.0259 0.0274
07:01-08:00, Tue., 18 Nov. 0.0298 0.0253 0.0273
06:01-07:00, Tue., 18 Nov. 0.0290 0.0253 0.0271
05:01-06:00, Tue., 18 Nov. 0.0292 0.0256 0.0272
04:01-05:00, Tue., 18 Nov. 0.0289 0.0252 0.0270
03:01-04:00, Tue., 18 Nov. 0.0286 0.0247 0.0270
02:01-03:00, Tue., 18 Nov. 0.0296 0.0246 0.0268
01:01-02:00, Tue., 18 Nov. 0.0291 0.0248 0.0269
00:01-01:00, Tue., 18 Nov. 0.0291 0.0256 0.0270
23:01-24:00, Mon., 17 Nov. 0.0292 0.0248 0.0275
22:01-23:00, Mon., 17 Nov. 0.0291 0.0255 0.0273
21:01-22:00, Mon., 17 Nov. 0.0286 0.0252 0.0271
20:01-21:00, Mon., 17 Nov. 0.0294 0.0249 0.0272
19:01-20:00, Mon., 17 Nov. 0.0285 0.0246 0.0269
18:01-19:00, Mon., 17 Nov. 0.0285 0.0244 0.0266
17:01-18:00, Mon., 17 Nov. 0.0286 0.0245 0.0266
16:01-17:00, Mon., 17 Nov. 0.0287 0.0249 0.0265
15:01-16:00, Mon., 17 Nov. 0.0296 0.0249 0.0272
14:01-15:00, Mon., 17 Nov. 0.0297 0.0249 0.0272
13:01-14:00, Mon., 17 Nov. 0.0295 0.0252 0.0271
12:01-13:00, Mon., 17 Nov. 0.0289 0.0249 0.0270
11:01-12:00, Mon., 17 Nov. 0.0290 0.0245 0.0269
10:01-11:00, Mon., 17 Nov. 0.0283 0.0249 0.0269
09:01-10:00, Mon., 17 Nov. 0.0300 0.0245 0.0272
08:01-09:00, Mon., 17 Nov. 0.0297 0.0253 0.0275
07:01-08:00, Mon., 17 Nov. 0.0298 0.0263 0.0280
06:01-07:00, Mon., 17 Nov. 0.0307 0.0257 0.0281
05:01-06:00, Mon., 17 Nov. 0.0309 0.0263 0.0283
04:01-05:00, Mon., 17 Nov. 0.0301 0.0266 0.0283
03:01-04:00, Mon., 17 Nov. 0.0299 0.0261 0.0281
02:01-03:00, Mon., 17 Nov. 0.0301 0.0262 0.0279
01:01-02:00, Mon., 17 Nov. 0.0294 0.0258 0.0275
00:01-01:00, Mon., 17 Nov. 0.0296 0.0261 0.0277
23:01-24:00, Sun., 16 Nov. 0.0295 0.0256 0.0276
22:01-23:00, Sun., 16 Nov. 0.0290 0.0248 0.0272
21:01-22:00, Sun., 16 Nov. 0.0301 0.0247 0.0274
20:01-21:00, Sun., 16 Nov. 0.0285 0.0250 0.0269
19:01-20:00, Sun., 16 Nov. 0.0296 0.0247 0.0266
18:01-19:00, Sun., 16 Nov. 0.0287 0.0249 0.0266
17:01-18:00, Sun., 16 Nov. 0.0291 0.0245 0.0264
16:01-17:00, Sun., 16 Nov. 0.0283 0.0245 0.0264
15:01-16:00, Sun., 16 Nov. 0.0294 0.0248 0.0265
14:01-15:00, Sun., 16 Nov. 0.0286 0.0245 0.0266
13:01-14:00, Sun., 16 Nov. 0.0284 0.0251 0.0269
12:01-13:00, Sun., 16 Nov. 0.0290 0.0252 0.0270
11:01-12:00, Sun., 16 Nov. 0.0290 0.0254 0.0273
10:01-11:00, Sun., 16 Nov. 0.0296 0.0252 0.0273
09:01-10:00, Sun., 16 Nov. 0.0300 0.0251 0.0276
08:01-09:00, Sun., 16 Nov. 0.0295 0.0259 0.0276
07:01-08:00, Sun., 16 Nov. 0.0287 0.0257 0.0275
06:01-07:00, Sun., 16 Nov. 0.0290 0.0258 0.0274
05:01-06:00, Sun., 16 Nov. 0.0292 0.0254 0.0274
04:01-05:00, Sun., 16 Nov. 0.0292 0.0245 0.0271
03:01-04:00, Sun., 16 Nov. 0.0293 0.0254 0.0275
02:01-03:00, Sun., 16 Nov. 0.0299 0.0257 0.0274
01:01-02:00, Sun., 16 Nov. 0.0297 0.0250 0.0273
00:01-01:00, Sun., 16 Nov. 0.0293 0.0254 0.0275
23:01-24:00, Sat., 15 Nov. 0.0293 0.0254 0.0270
22:01-23:00, Sat., 15 Nov. 0.0286 0.0244 0.0268
21:01-22:00, Sat., 15 Nov. 0.0283 0.0237 0.0264
20:01-21:00, Sat., 15 Nov. 0.0279 0.0238 0.0260
19:01-20:00, Sat., 15 Nov. 0.0283 0.0245 0.0263
18:01-19:00, Sat., 15 Nov. 0.0288 0.0246 0.0264
17:01-18:00, Sat., 15 Nov. 0.0285 0.0246 0.0267
16:01-17:00, Sat., 15 Nov. 0.0284 0.0254 0.0267
15:01-16:00, Sat., 15 Nov. 0.0289 0.0249 0.0267
14:01-15:00, Sat., 15 Nov. 0.0291 0.0246 0.0268
13:01-14:00, Sat., 15 Nov. 0.0286 0.0256 0.0271
12:01-13:00, Sat., 15 Nov. 0.0292 0.0252 0.0269
11:01-12:00, Sat., 15 Nov. 0.0286 0.0250 0.0269
10:01-11:00, Sat., 15 Nov. 0.0289 0.0257 0.0274
09:01-10:00, Sat., 15 Nov. 0.0303 0.0251 0.0272
08:01-09:00, Sat., 15 Nov. 0.0299 0.0249 0.0277
07:01-08:00, Sat., 15 Nov. 0.0293 0.0252 0.0274
06:01-07:00, Sat., 15 Nov. 0.0302 0.0248 0.0271
05:01-06:00, Sat., 15 Nov. 0.0303 0.0249 0.0271
04:01-05:00, Sat., 15 Nov. 0.0288 0.0256 0.0272
03:01-04:00, Sat., 15 Nov. 0.0295 0.0246 0.0269
02:01-03:00, Sat., 15 Nov. 0.0280 0.0248 0.0265
01:01-02:00, Sat., 15 Nov. 0.0286 0.0249 0.0269
00:01-01:00, Sat., 15 Nov. 0.0283 0.0246 0.0266
23:01-24:00, Fri., 14 Nov. 0.0283 0.0249 0.0265
22:01-23:00, Fri., 14 Nov. 0.0283 0.0241 0.0264
21:01-22:00, Fri., 14 Nov. 0.0299 0.0238 0.0264
20:01-21:00, Fri., 14 Nov. 0.0286 0.0249 0.0266
19:01-20:00, Fri., 14 Nov. 0.0280 0.0248 0.0265
18:01-19:00, Fri., 14 Nov. 0.0284 0.0248 0.0265
17:01-18:00, Fri., 14 Nov. 0.0289 0.0246 0.0268
16:01-17:00, Fri., 14 Nov. 0.0280 0.0235 0.0265
15:01-16:00, Fri., 14 Nov. 0.0289 0.0250 0.0269
14:01-15:00, Fri., 14 Nov. 0.0287 0.0246 0.0271
13:01-14:00, Fri., 14 Nov. 0.0286 0.0248 0.0270
12:01-13:00, Fri., 14 Nov. 0.0283 0.0249 0.0269
11:01-12:00, Fri., 14 Nov. 0.0293 0.0258 0.0272
10:01-11:00, Fri., 14 Nov. 0.0294 0.0254 0.0274
09:01-10:00, Fri., 14 Nov. 0.0307 0.0266 0.0281
08:01-09:00, Fri., 14 Nov. 0.0302 0.0265 0.0286
07:01-08:00, Fri., 14 Nov. 0.0310 0.0263 0.0288
06:01-07:00, Fri., 14 Nov. 0.0319 0.0270 0.0289
05:01-06:00, Fri., 14 Nov. 0.0313 0.0273 0.0294
04:01-05:00, Fri., 14 Nov. 0.0315 0.0273 0.0291
03:01-04:00, Fri., 14 Nov. 0.0305 0.0267 0.0288
02:01-03:00, Fri., 14 Nov. 0.0304 0.0272 0.0287
01:01-02:00, Fri., 14 Nov. 0.0309 0.0272 0.0291
00:01-01:00, Fri., 14 Nov. 0.0306 0.0273 0.0290
23:01-24:00, Thu., 13 Nov. 0.0314 0.0280 0.0292
22:01-23:00, Thu., 13 Nov. 0.0314 0.0273 0.0294
21:01-22:00, Thu., 13 Nov. 0.0310 0.0267 0.0290
20:01-21:00, Thu., 13 Nov. 0.0308 0.0266 0.0282
19:01-20:00, Thu., 13 Nov. 0.0297 0.0259 0.0276
18:01-19:00, Thu., 13 Nov. 0.0296 0.0258 0.0274
17:01-18:00, Thu., 13 Nov. 0.0297 0.0254 0.0275
16:01-17:00, Thu., 13 Nov. 0.0294 0.0258 0.0275
15:01-16:00, Thu., 13 Nov. 0.0304 0.0259 0.0278
14:01-15:00, Thu., 13 Nov. 0.0297 0.0262 0.0279
13:01-14:00, Thu., 13 Nov. 0.0298 0.0259 0.0281
12:01-13:00, Thu., 13 Nov. 0.0304 0.0270 0.0286
11:01-12:00, Thu., 13 Nov. 0.0298 0.0263 0.0280
10:01-11:00, Thu., 13 Nov. 0.0299 0.0264 0.0281
09:01-10:00, Thu., 13 Nov. 0.0302 0.0263 0.0281
08:01-09:00, Thu., 13 Nov. 0.0304 0.0264 0.0285
07:01-08:00, Thu., 13 Nov. 0.0304 0.0266 0.0281
06:01-07:00, Thu., 13 Nov. 0.0308 0.0263 0.0285
05:01-06:00, Thu., 13 Nov. 0.0317 0.0269 0.0285
04:01-05:00, Thu., 13 Nov. 0.0294 0.0256 0.0278
03:01-04:00, Thu., 13 Nov. 0.0293 0.0262 0.0276
02:01-03:00, Thu., 13 Nov. 0.0304 0.0256 0.0275
01:01-02:00, Thu., 13 Nov. 0.0304 0.0260 0.0279
00:01-01:00, Thu., 13 Nov. 0.0306 0.0266 0.0281
23:01-24:00, Wed., 12 Nov. 0.0300 0.0253 0.0277
22:01-23:00, Wed., 12 Nov. 0.0292 0.0243 0.0273
21:01-22:00, Wed., 12 Nov. 0.0283 0.0245 0.0267
20:01-21:00, Wed., 12 Nov. 0.0283 0.0242 0.0266
19:01-20:00, Wed., 12 Nov. 0.0290 0.0245 0.0264
18:01-19:00, Wed., 12 Nov. 0.0280 0.0245 0.0262
17:01-18:00, Wed., 12 Nov. 0.0287 0.0241 0.0262
16:01-17:00, Wed., 12 Nov. 0.0284 0.0248 0.0263
15:01-16:00, Wed., 12 Nov. 0.0283 0.0245 0.0264
14:01-15:00, Wed., 12 Nov. 0.0286 0.0245 0.0265
13:01-14:00, Wed., 12 Nov. 0.0286 0.0253 0.0266
12:01-13:00, Wed., 12 Nov. 0.0285 0.0248 0.0266
11:01-12:00, Wed., 12 Nov. 0.0287 0.0249 0.0268
10:01-11:00, Wed., 12 Nov. 0.0290 0.0245 0.0266
09:01-10:00, Wed., 12 Nov. 0.0288 0.0242 0.0266
08:01-09:00, Wed., 12 Nov. 0.0289 0.0245 0.0266
07:01-08:00, Wed., 12 Nov. 0.0287 0.0250 0.0267
06:01-07:00, Wed., 12 Nov. 0.0280 0.0248 0.0266
05:01-06:00, Wed., 12 Nov. 0.0288 0.0237 0.0265
04:01-05:00, Wed., 12 Nov. 0.0287 0.0245 0.0266
03:01-04:00, Wed., 12 Nov. 0.0285 0.0244 0.0265
02:01-03:00, Wed., 12 Nov. 0.0292 0.0249 0.0271
01:01-02:00, Wed., 12 Nov. 0.0285 0.0249 0.0267
00:01-01:00, Wed., 12 Nov. 0.0290 0.0247 0.0267
23:01-24:00, Tue., 11 Nov. 0.0288 0.0245 0.0265
22:01-23:00, Tue., 11 Nov. 0.0286 0.0249 0.0266
21:01-22:00, Tue., 11 Nov. 0.0287 0.0250 0.0267
20:01-21:00, Tue., 11 Nov. 0.0287 0.0248 0.0266
19:01-20:00, Tue., 11 Nov. 0.0286 0.0238 0.0263
18:01-19:00, Tue., 11 Nov. 0.0287 0.0246 0.0266
17:01-18:00, Tue., 11 Nov. 0.0286 0.0244 0.0265
16:01-17:00, Tue., 11 Nov. 0.0294 0.0245 0.0266
15:01-16:00, Tue., 11 Nov. 0.0297 0.0254 0.0271
14:01-15:00, Tue., 11 Nov. 0.0294 0.0249 0.0273
13:01-14:00, Tue., 11 Nov. 0.0289 0.0252 0.0271
12:01-13:00, Tue., 11 Nov. 0.0289 0.0255 0.0269
11:01-12:00, Tue., 11 Nov. 0.0293 0.0253 0.0272
10:01-11:00, Tue., 11 Nov. 0.0293 0.0253 0.0273
09:01-10:00, Tue., 11 Nov. 0.0305 0.0253 0.0278
08:01-09:00, Tue., 11 Nov. 0.0308 0.0259 0.0285
07:01-08:00, Tue., 11 Nov. 0.0307 0.0266 0.0283
06:01-07:00, Tue., 11 Nov. 0.0302 0.0262 0.0286
05:01-06:00, Tue., 11 Nov. 0.0309 0.0259 0.0278
04:01-05:00, Tue., 11 Nov. 0.0297 0.0259 0.0278
03:01-04:00, Tue., 11 Nov. 0.0298 0.0256 0.0278
02:01-03:00, Tue., 11 Nov. 0.0290 0.0259 0.0273