A Radiant Story

“Incidentally, disturbance from cosmic background radiation is something we have all experienced. Tune your television to any channel it doesn't receive, and about 1 percent of the dancing static you see is accounted for by this ancient remnant of the Big Bang. The next time you complain that there is nothing on, remember that you can always watch the birth of the universe.”
-Bill Bryson

Flickr.com has a interesting story and graph about radiation. An  executive at a Silicon Valley tech firm (San Francisco) traveled to Japan for business.  One of his destinations was 50 miles from the crippled Fukushima Daiichi nuclear power plant that generated much frantic news after the big earthquake.

"As a precaution, a colleague gave him a Geiger Counter so he could make sure it wasn’t getting dangerous as he approached the plant."

Instead of only running the Geiger Counter near the site of the nuclear meltdown, the executive left it on the entire trip with fascinating results below. The tiny bump near hour 144 is the exposure from the damaged nuclear power plant. The much larger spikes occured while flying. San Francisco to Hong Kong, Hong Kong to Singapore, Singapore to Tokyo, and Tokyo back to San Francisco. This is completely normal - a plane a mile or two up has less atmosphere to block in comming radiation from the sun and from space. The last trip has an extra tall spike because the flight went near the North Pole which blocks even less radiation than other parts of the globe.

Bottom Line

It helps to put things in perspective. Yes the radiation at the plant is bad and a meltdown did occur - BUT the effect is very local and dimishes rapidly. Persons living nearby (50 miles or so) need to be concerned about long-term accumulative risk. Visitors and tourists get greater exposure from the flight to Japan than from the damaged nuclear plant.