Radiation is Scary - But It's All Around Us

Like most folks, I've been watching the TV reports of the disaster in Japan. I'm in awe of the courage and persistence of the nuclear plant workers. They didn't give up, despite the hazards, and they seem to be gaining the upper hand. And the populace hasn't panicked.

What about those face masks so many Japanese are wearing? They won't do any good against gamma rays, but they can be very effective against alpha particles. You don't want alpha particles to get inside your body.

Does all this mean we must abandon nuclear power?

No.

How hazardous is nuclear power?

Today's Dot Earth blog on the New York Times site addresses the issue of "Dread to Risk." The article is worth reading. The most interesting link is to a chart comparing radiation dosage in various circumstances. It shows, for example, that eating a single banana exposes one to more radiation than living for a year in the vicinity of a nuclear generation plant. Living near a coal powered generation plant exposes you to three times as much radiation as living near a nuclear plant. Take a look at the table.

The risk is low. But clearly not zero in case of a major disaster such as an earthquake and tsunami.

The present disaster in Japan is a result of the 40-year old design, which requires a very complex cooling system with backups.

What this suggests is that we should investigate other types of nuclear reactors. The most dangerous kind of reactor is the graphite moderated reactor of the Chernobyl variety. Next most dangerous are the boiling water reactors like Three Mile Island and like those used in Japan. A better reactor type is the pressure water reactors like many of our newer reactors.

All of these reactors require intact and functional cooling systems to insure safety.

China is moving ahead with an ambitious plan to mass produce an inherently safe reactor design, known as a pebble bed reactor. There are other candidate designs that will not overheat and explode if cooling fails.

It is past time to invest in safer designs.

One thing to remember: there is no risk-free way of producing and using the large amounts of energy needed for modern civilization.

Each year, about 2500 Americans die in residential fires. Many of these happen in winter and result from use of kerosene heaters.

Let's put our hazards in perspective.