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
07:01-08:00, Sat., 22 Aug. 0.0269 0.0227 0.0251
06:01-07:00, Sat., 22 Aug. 0.0283 0.0231 0.0252
05:01-06:00, Sat., 22 Aug. 0.0274 0.0235 0.0253
04:01-05:00, Sat., 22 Aug. 0.0272 0.0230 0.0249
03:01-04:00, Sat., 22 Aug. 0.0268 0.0231 0.0249
02:01-03:00, Sat., 22 Aug. 0.0263 0.0223 0.0246
01:01-02:00, Sat., 22 Aug. 0.0273 0.0225 0.0248
00:01-01:00, Sat., 22 Aug. 0.0269 0.0225 0.0246
23:01-24:00, Fri., 21 Aug. 0.0273 0.0229 0.0249
22:01-23:00, Fri., 21 Aug. 0.0289 0.0242 0.0267
21:01-22:00, Fri., 21 Aug. 0.0357 0.0271 0.0317
20:01-21:00, Fri., 21 Aug. 0.0379 0.0306 0.0351
19:01-20:00, Fri., 21 Aug. 0.0320 0.0225 0.0265
18:01-19:00, Fri., 21 Aug. 0.0262 0.0224 0.0243
17:01-18:00, Fri., 21 Aug. 0.0263 0.0224 0.0245
16:01-17:00, Fri., 21 Aug. 0.0273 0.0228 0.0249
15:01-16:00, Fri., 21 Aug. 0.0279 0.0238 0.0259
14:01-15:00, Fri., 21 Aug. 0.0283 0.0238 0.0265
13:01-14:00, Fri., 21 Aug. 0.0263 0.0230 0.0246
12:01-13:00, Fri., 21 Aug. 0.0263 0.0220 0.0247
11:01-12:00, Fri., 21 Aug. 0.0265 0.0231 0.0246
10:01-11:00, Fri., 21 Aug. 0.0274 0.0225 0.0248
09:01-10:00, Fri., 21 Aug. 0.0271 0.0231 0.0249
08:01-09:00, Fri., 21 Aug. 0.0276 0.0236 0.0253
07:01-08:00, Fri., 21 Aug. 0.0277 0.0231 0.0253
06:01-07:00, Fri., 21 Aug. 0.0269 0.0235 0.0253
05:01-06:00, Fri., 21 Aug. 0.0272 0.0237 0.0254
04:01-05:00, Fri., 21 Aug. 0.0269 0.0230 0.0249
03:01-04:00, Fri., 21 Aug. 0.0266 0.0221 0.0246
02:01-03:00, Fri., 21 Aug. 0.0264 0.0224 0.0246
01:01-02:00, Fri., 21 Aug. 0.0262 0.0222 0.0245
00:01-01:00, Fri., 21 Aug. 0.0266 0.0217 0.0244
23:01-24:00, Thu., 20 Aug. 0.0271 0.0224 0.0246
22:01-23:00, Thu., 20 Aug. 0.0273 0.0229 0.0245
21:01-22:00, Thu., 20 Aug. 0.0271 0.0229 0.0249
20:01-21:00, Thu., 20 Aug. 0.0273 0.0226 0.0249
19:01-20:00, Thu., 20 Aug. 0.0264 0.0227 0.0246
18:01-19:00, Thu., 20 Aug. 0.0267 0.0225 0.0246
17:01-18:00, Thu., 20 Aug. 0.0284 0.0227 0.0246
16:01-17:00, Thu., 20 Aug. 0.0266 0.0222 0.0244
15:01-16:00, Thu., 20 Aug. 0.0283 0.0228 0.0247
14:01-15:00, Thu., 20 Aug. 0.0263 0.0230 0.0247
13:01-14:00, Thu., 20 Aug. 0.0262 0.0226 0.0245
12:01-13:00, Thu., 20 Aug. 0.0269 0.0228 0.0246
11:01-12:00, Thu., 20 Aug. 0.0266 0.0227 0.0245
10:01-11:00, Thu., 20 Aug. 0.0266 0.0229 0.0248
09:01-10:00, Thu., 20 Aug. 0.0273 0.0229 0.0251
08:01-09:00, Thu., 20 Aug. 0.0271 0.0233 0.0252
07:01-08:00, Thu., 20 Aug. 0.0266 0.0228 0.0247
06:01-07:00, Thu., 20 Aug. 0.0265 0.0230 0.0247
05:01-06:00, Thu., 20 Aug. 0.0270 0.0228 0.0245
04:01-05:00, Thu., 20 Aug. 0.0262 0.0224 0.0244
03:01-04:00, Thu., 20 Aug. 0.0259 0.0224 0.0243
02:01-03:00, Thu., 20 Aug. 0.0266 0.0221 0.0244
01:01-02:00, Thu., 20 Aug. 0.0262 0.0225 0.0245
00:01-01:00, Thu., 20 Aug. 0.0262 0.0226 0.0245
23:01-24:00, Wed., 19 Aug. 0.0262 0.0217 0.0242
22:01-23:00, Wed., 19 Aug. 0.0265 0.0224 0.0243
21:01-22:00, Wed., 19 Aug. 0.0262 0.0220 0.0241
20:01-21:00, Wed., 19 Aug. 0.0263 0.0221 0.0242
19:01-20:00, Wed., 19 Aug. 0.0264 0.0225 0.0242
18:01-19:00, Wed., 19 Aug. 0.0266 0.0226 0.0245
17:01-18:00, Wed., 19 Aug. 0.0267 0.0225 0.0244
16:01-17:00, Wed., 19 Aug. 0.0263 0.0227 0.0243
15:01-16:00, Wed., 19 Aug. 0.0268 0.0225 0.0245
14:01-15:00, Wed., 19 Aug. 0.0273 0.0228 0.0246
13:01-14:00, Wed., 19 Aug. 0.0260 0.0226 0.0244
12:01-13:00, Wed., 19 Aug. 0.0264 0.0224 0.0244
11:01-12:00, Wed., 19 Aug. 0.0271 0.0225 0.0246
10:01-11:00, Wed., 19 Aug. 0.0272 0.0231 0.0251
09:01-10:00, Wed., 19 Aug. 0.0273 0.0233 0.0250
08:01-09:00, Wed., 19 Aug. 0.0269 0.0231 0.0252
07:01-08:00, Wed., 19 Aug. 0.0271 0.0228 0.0252
06:01-07:00, Wed., 19 Aug. 0.0273 0.0243 0.0258
05:01-06:00, Wed., 19 Aug. 0.0273 0.0235 0.0254
04:01-05:00, Wed., 19 Aug. 0.0265 0.0224 0.0244
03:01-04:00, Wed., 19 Aug. 0.0261 0.0225 0.0244
02:01-03:00, Wed., 19 Aug. 0.0265 0.0229 0.0245
01:01-02:00, Wed., 19 Aug. 0.0267 0.0223 0.0244
00:01-01:00, Wed., 19 Aug. 0.0262 0.0225 0.0244
23:01-24:00, Tue., 18 Aug. 0.0263 0.0221 0.0242
22:01-23:00, Tue., 18 Aug. 0.0262 0.0217 0.0241
21:01-22:00, Tue., 18 Aug. 0.0265 0.0226 0.0241
20:01-21:00, Tue., 18 Aug. 0.0259 0.0224 0.0241
19:01-20:00, Tue., 18 Aug. 0.0263 0.0217 0.0243
18:01-19:00, Tue., 18 Aug. 0.0259 0.0223 0.0241
17:01-18:00, Tue., 18 Aug. 0.0270 0.0221 0.0242
16:01-17:00, Tue., 18 Aug. 0.0264 0.0221 0.0242
15:01-16:00, Tue., 18 Aug. 0.0266 0.0224 0.0243
14:01-15:00, Tue., 18 Aug. 0.0260 0.0221 0.0243
13:01-14:00, Tue., 18 Aug. 0.0263 0.0220 0.0242
12:01-13:00, Tue., 18 Aug. 0.0267 0.0221 0.0242
11:01-12:00, Tue., 18 Aug. 0.0268 0.0226 0.0243
10:01-11:00, Tue., 18 Aug. 0.0263 0.0229 0.0246
09:01-10:00, Tue., 18 Aug. 0.0265 0.0222 0.0247
08:01-09:00, Tue., 18 Aug. 0.0270 0.0237 0.0251
07:01-08:00, Tue., 18 Aug. 0.0286 0.0242 0.0261
06:01-07:00, Tue., 18 Aug. 0.0282 0.0242 0.0264
05:01-06:00, Tue., 18 Aug. 0.0287 0.0242 0.0264
04:01-05:00, Tue., 18 Aug. 0.0268 0.0233 0.0253
03:01-04:00, Tue., 18 Aug. 0.0262 0.0223 0.0246
02:01-03:00, Tue., 18 Aug. 0.0259 0.0228 0.0243
01:01-02:00, Tue., 18 Aug. 0.0257 0.0221 0.0241
00:01-01:00, Tue., 18 Aug. 0.0263 0.0225 0.0242
23:01-24:00, Mon., 17 Aug. 0.0259 0.0227 0.0242
22:01-23:00, Mon., 17 Aug. 0.0260 0.0225 0.0241
21:01-22:00, Mon., 17 Aug. 0.0256 0.0220 0.0238
20:01-21:00, Mon., 17 Aug. 0.0258 0.0221 0.0242
19:01-20:00, Mon., 17 Aug. 0.0260 0.0222 0.0241
18:01-19:00, Mon., 17 Aug. 0.0260 0.0218 0.0241
17:01-18:00, Mon., 17 Aug. 0.0262 0.0223 0.0243
16:01-17:00, Mon., 17 Aug. 0.0259 0.0215 0.0240
15:01-16:00, Mon., 17 Aug. 0.0264 0.0224 0.0243
14:01-15:00, Mon., 17 Aug. 0.0259 0.0217 0.0241
13:01-14:00, Mon., 17 Aug. 0.0270 0.0226 0.0240
12:01-13:00, Mon., 17 Aug. 0.0260 0.0220 0.0242
11:01-12:00, Mon., 17 Aug. 0.0263 0.0217 0.0242
10:01-11:00, Mon., 17 Aug. 0.0261 0.0224 0.0241
09:01-10:00, Mon., 17 Aug. 0.0266 0.0217 0.0240
08:01-09:00, Mon., 17 Aug. 0.0260 0.0220 0.0240
07:01-08:00, Mon., 17 Aug. 0.0266 0.0217 0.0239
06:01-07:00, Mon., 17 Aug. 0.0263 0.0218 0.0240
05:01-06:00, Mon., 17 Aug. 0.0256 0.0223 0.0240
04:01-05:00, Mon., 17 Aug. 0.0267 0.0226 0.0241
03:01-04:00, Mon., 17 Aug. 0.0259 0.0221 0.0238
02:01-03:00, Mon., 17 Aug. 0.0260 0.0221 0.0239
01:01-02:00, Mon., 17 Aug. 0.0255 0.0222 0.0241
00:01-01:00, Mon., 17 Aug. 0.0263 0.0225 0.0241
23:01-24:00, Sun., 16 Aug. 0.0261 0.0224 0.0240
22:01-23:00, Sun., 16 Aug. 0.0256 0.0224 0.0237
21:01-22:00, Sun., 16 Aug. 0.0260 0.0221 0.0240
20:01-21:00, Sun., 16 Aug. 0.0258 0.0213 0.0239
19:01-20:00, Sun., 16 Aug. 0.0262 0.0219 0.0241
18:01-19:00, Sun., 16 Aug. 0.0270 0.0222 0.0249
17:01-18:00, Sun., 16 Aug. 0.0276 0.0235 0.0258
16:01-17:00, Sun., 16 Aug. 0.0287 0.0245 0.0261
15:01-16:00, Sun., 16 Aug. 0.0282 0.0234 0.0259
14:01-15:00, Sun., 16 Aug. 0.0268 0.0228 0.0249
13:01-14:00, Sun., 16 Aug. 0.0263 0.0217 0.0246
12:01-13:00, Sun., 16 Aug. 0.0264 0.0232 0.0248
11:01-12:00, Sun., 16 Aug. 0.0266 0.0217 0.0242
10:01-11:00, Sun., 16 Aug. 0.0263 0.0221 0.0243
09:01-10:00, Sun., 16 Aug. 0.0262 0.0228 0.0244
08:01-09:00, Sun., 16 Aug. 0.0268 0.0222 0.0244
07:01-08:00, Sun., 16 Aug. 0.0263 0.0228 0.0244
06:01-07:00, Sun., 16 Aug. 0.0267 0.0226 0.0245
05:01-06:00, Sun., 16 Aug. 0.0268 0.0219 0.0242
04:01-05:00, Sun., 16 Aug. 0.0256 0.0226 0.0243
03:01-04:00, Sun., 16 Aug. 0.0265 0.0222 0.0244
02:01-03:00, Sun., 16 Aug. 0.0262 0.0223 0.0242
01:01-02:00, Sun., 16 Aug. 0.0262 0.0223 0.0240
00:01-01:00, Sun., 16 Aug. 0.0262 0.0222 0.0241
23:01-24:00, Sat., 15 Aug. 0.0262 0.0226 0.0241
22:01-23:00, Sat., 15 Aug. 0.0263 0.0220 0.0243
21:01-22:00, Sat., 15 Aug. 0.0263 0.0224 0.0242
20:01-21:00, Sat., 15 Aug. 0.0257 0.0223 0.0241
19:01-20:00, Sat., 15 Aug. 0.0259 0.0222 0.0241
18:01-19:00, Sat., 15 Aug. 0.0259 0.0224 0.0242
17:01-18:00, Sat., 15 Aug. 0.0262 0.0217 0.0240
16:01-17:00, Sat., 15 Aug. 0.0263 0.0220 0.0240
15:01-16:00, Sat., 15 Aug. 0.0265 0.0221 0.0242
14:01-15:00, Sat., 15 Aug. 0.0259 0.0221 0.0241
13:01-14:00, Sat., 15 Aug. 0.0259 0.0225 0.0240
12:01-13:00, Sat., 15 Aug. 0.0263 0.0213 0.0240
11:01-12:00, Sat., 15 Aug. 0.0262 0.0223 0.0240
10:01-11:00, Sat., 15 Aug. 0.0258 0.0213 0.0240
09:01-10:00, Sat., 15 Aug. 0.0263 0.0226 0.0242
08:01-09:00, Sat., 15 Aug. 0.0257 0.0222 0.0239
07:01-08:00, Sat., 15 Aug. 0.0258 0.0219 0.0239
06:01-07:00, Sat., 15 Aug. 0.0260 0.0218 0.0240
05:01-06:00, Sat., 15 Aug. 0.0254 0.0215 0.0238
04:01-05:00, Sat., 15 Aug. 0.0255 0.0225 0.0240
03:01-04:00, Sat., 15 Aug. 0.0276 0.0224 0.0247
02:01-03:00, Sat., 15 Aug. 0.0273 0.0233 0.0256
01:01-02:00, Sat., 15 Aug. 0.0272 0.0221 0.0246
00:01-01:00, Sat., 15 Aug. 0.0262 0.0224 0.0242
23:01-24:00, Fri., 14 Aug. 0.0263 0.0228 0.0244
22:01-23:00, Fri., 14 Aug. 0.0272 0.0225 0.0243
21:01-22:00, Fri., 14 Aug. 0.0263 0.0218 0.0244
20:01-21:00, Fri., 14 Aug. 0.0264 0.0223 0.0241
19:01-20:00, Fri., 14 Aug. 0.0263 0.0222 0.0241
18:01-19:00, Fri., 14 Aug. 0.0258 0.0227 0.0243
17:01-18:00, Fri., 14 Aug. 0.0265 0.0220 0.0240
16:01-17:00, Fri., 14 Aug. 0.0265 0.0229 0.0245
15:01-16:00, Fri., 14 Aug. 0.0261 0.0224 0.0243
14:01-15:00, Fri., 14 Aug. 0.0265 0.0228 0.0246
13:01-14:00, Fri., 14 Aug. 0.0262 0.0224 0.0243
12:01-13:00, Fri., 14 Aug. 0.0258 0.0221 0.0243
11:01-12:00, Fri., 14 Aug. 0.0256 0.0227 0.0243
10:01-11:00, Fri., 14 Aug. 0.0256 0.0224 0.0241
09:01-10:00, Fri., 14 Aug. 0.0267 0.0225 0.0244
08:01-09:00, Fri., 14 Aug. 0.0268 0.0221 0.0243
07:01-08:00, Fri., 14 Aug. 0.0266 0.0224 0.0243
06:01-07:00, Fri., 14 Aug. 0.0267 0.0227 0.0247
05:01-06:00, Fri., 14 Aug. 0.0260 0.0225 0.0245
04:01-05:00, Fri., 14 Aug. 0.0274 0.0233 0.0249
03:01-04:00, Fri., 14 Aug. 0.0276 0.0235 0.0254
02:01-03:00, Fri., 14 Aug. 0.0290 0.0245 0.0267
01:01-02:00, Fri., 14 Aug. 0.0335 0.0272 0.0301
00:01-01:00, Fri., 14 Aug. 0.0313 0.0273 0.0295
23:01-24:00, Thu., 13 Aug. 0.0311 0.0268 0.0291
22:01-23:00, Thu., 13 Aug. 0.0309 0.0270 0.0287
21:01-22:00, Thu., 13 Aug. 0.0298 0.0249 0.0273
20:01-21:00, Thu., 13 Aug. 0.0294 0.0239 0.0262
19:01-20:00, Thu., 13 Aug. 0.0280 0.0231 0.0249
18:01-19:00, Thu., 13 Aug. 0.0270 0.0235 0.0251
17:01-18:00, Thu., 13 Aug. 0.0280 0.0231 0.0254
16:01-17:00, Thu., 13 Aug. 0.0307 0.0241 0.0277
15:01-16:00, Thu., 13 Aug. 0.0295 0.0230 0.0259
14:01-15:00, Thu., 13 Aug. 0.0269 0.0221 0.0247
13:01-14:00, Thu., 13 Aug. 0.0273 0.0227 0.0255
12:01-13:00, Thu., 13 Aug. 0.0296 0.0258 0.0274
11:01-12:00, Thu., 13 Aug. 0.0326 0.0259 0.0295
10:01-11:00, Thu., 13 Aug. 0.0299 0.0246 0.0269
09:01-10:00, Thu., 13 Aug. 0.0281 0.0242 0.0262
08:01-09:00, Thu., 13 Aug. 0.0293 0.0255 0.0276
07:01-08:00, Thu., 13 Aug. 0.0288 0.0235 0.0257
06:01-07:00, Thu., 13 Aug. 0.0265 0.0230 0.0247
05:01-06:00, Thu., 13 Aug. 0.0265 0.0225 0.0243
04:01-05:00, Thu., 13 Aug. 0.0267 0.0229 0.0247
03:01-04:00, Thu., 13 Aug. 0.0266 0.0222 0.0244
02:01-03:00, Thu., 13 Aug. 0.0258 0.0225 0.0243
01:01-02:00, Thu., 13 Aug. 0.0262 0.0224 0.0243
00:01-01:00, Thu., 13 Aug. 0.0263 0.0224 0.0243
23:01-24:00, Wed., 12 Aug. 0.0260 0.0226 0.0243
22:01-23:00, Wed., 12 Aug. 0.0264 0.0217 0.0245
21:01-22:00, Wed., 12 Aug. 0.0266 0.0224 0.0244
20:01-21:00, Wed., 12 Aug. 0.0266 0.0231 0.0248
19:01-20:00, Wed., 12 Aug. 0.0273 0.0229 0.0250
18:01-19:00, Wed., 12 Aug. 0.0270 0.0231 0.0250
17:01-18:00, Wed., 12 Aug. 0.0287 0.0237 0.0265
16:01-17:00, Wed., 12 Aug. 0.0319 0.0261 0.0291
15:01-16:00, Wed., 12 Aug. 0.0329 0.0228 0.0284
14:01-15:00, Wed., 12 Aug. 0.0275 0.0228 0.0247
13:01-14:00, Wed., 12 Aug. 0.0273 0.0229 0.0253
12:01-13:00, Wed., 12 Aug. 0.0281 0.0229 0.0257
11:01-12:00, Wed., 12 Aug. 0.0263 0.0229 0.0246
10:01-11:00, Wed., 12 Aug. 0.0270 0.0236 0.0250
09:01-10:00, Wed., 12 Aug. 0.0268 0.0228 0.0251
08:01-09:00, Wed., 12 Aug. 0.0284 0.0245 0.0262