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Citizens arm themselves with umbrellas, raincoats, boots, Korea Times, April 7, 2011:

[Emphasis Added]
... The Korea Institute of Nuclear Safety (KINS) said radioactive iodine and cesium were found in rainwater collected in the early morning at a checkpoint on the island. The concentration level of iodine-131 was 2.02 becquerels per liter (Bq/l), that of cesium-137, 0.538 Bq/l, and that of cesium-134, 0.333 Bq/l. ...

Following the news that minuscule radioactive substances were detected on Jeju, people in all parts of the country carried umbrellas to work or school even though the rainfall was light.

Parents had their children not only use umbrellas but also wear raincoats, rubber boots and even masks. Some of them gave their children a ride to school, with streets near schools congested.

In Gyeonggi Province, about 130 pre-, elementary and middle schools were closed after the regional educational office allowed school heads to close them if they deemed it necessary. More than 40 others shortened school hours. ...
Read the report here.

UCB Rain Water Sampling Results, University of California, Berkeley, Department of Nuclear Engineering:

Iodine-131 level in rainwater sample taken on the roof of Etcheverry Hall on UC Berkeley campus, March 23, 2011 from 9:06-18:00 PDT
20.1 Becquerel per liter (Bq/L)
Read the report here: 'Radioactive Iodine-131 in rainwater sample near San Francisco 18,100% above federal drinking water standard'

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