Wrong radiation readings

November 8, 2012

Radiation monitors underreport data

      http://www3.nhk.or.jp/daily/english/20121108_18.html

Hundreds of radiation monitors installed in Fukushima and surrounding prefectures have been found to show readings around 10 percent lower than the actual level.

The science ministry installed 675 of the devices to monitor radiation in 7 prefectures.

Fukushima Prefecture has 545, while other prefectures have 10 to 30 each.

The readings have been uploaded in real time on the Internet since April.

But the ministry was examining reports from residents and local governments that their monitors showed higher readings than the government's data.

It found that the detection of radiation was being partially blocked by a metal battery housing in the units, which lead to an underreporting of the levels by around 10 percent.

The ministry will spend about 1.8 million dollars to fix the monitors, starting next week.