An interesting video via ZeroHedge showing someone in Tokyo measuring the amount of radiation outside their home.

Before the video, a little background on radiation measurements.

The meter itself is measuring micro sieverts and normal back ground rates will be somewhere around the 0.05 to 0.2 mark depending on what rock types make up the general area. An area with a lot of granite will give a higher reading due to natural decay for example.

In the video the background level in the air seems to be a perfectly normal 0.1 micro sieverts and it only begins to get interesting when the counter is placed near a drain giving a reading of around 6 micro sieverts. Whether this is due to fall out from Fukushima or due to materials already present in the road surface is not clear but a general level of 6 microsieverts is not entirely healthy as helpfully spelled out in a comment from the article :

Background is about .07 micros. .10 may indicate you’ve got some particles in the wind. A huge slab of granite produces .11.

6 micros is a somewhat, dangerous amount for everyday exposure. If exposed continuously, this would give you 2.5 the limit of the dose limit for a nuclear worker is (20 milli per year). That’s 365 x 24 x 6 = 52 millis. Criterion for relocation at Chernobyl was 350 millis per lifetime. So after 7 years you’d need to move.

But the severity is just one aspect. It assumes the level is constant. Since the winds have only just started blowing onto Tokyo, with dinges and the arrival of typhoon season, we can expect levels to increase.

If indeed those levels are widespread (and one reading at one drain is far from conclusive obviously) then you have to start wondering where you move to exactly on a small island nation that is possibly equally irradiated?
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