Geiger Readings Across America: The Effects of Radiation in Everyday Life

How real is the risk, how safe is that airplane flight?

ByABC News
March 16, 2011, 8:21 AM

March 16, 2011 — -- Despite U.S. consumers' growing awareness of iodide pills, Geiger counters and emergency kits in the wake of Japan's nuclear scare, most people here have little to worry about, experts say.

Radiation, they say, is all around us, even inside of us, and it's perfectly safe for the most part.

To illustrate the point, ABC News took a Geiger counter around New York City to test different objects and locations. Even in the middle of Central Park, there is always a background level of radiation.

At a food stand in the park, a banana makes the Geiger counter rise a little bit. Bananas contain potassium, which people need to live, but is also radioactive.

At Grand Central Station, the meter on the Geiger counter moved a lot. Grand Central was built with granite and marble, which are both radioactive.

Eric Hall, a nuclear researcher at Columbia University in New York City, said that the thousands of people who walk through Grand Central every day are not at risk of getting sick because of the radioactivity around them.

"The doses are very, very small," Hall said.

Another activity that exposes people to radiation is air travel.

ABC News' Abbie Boudreau flew from Los Angeles to Denver to test the radiation levels during a flight.

"We're just about to take off on our flight and I turned the device on and it's going back and forth between .01 and .02," Boudreau said of the dose in millisieverts.

An hour and a half into the flight, at 40,000 feet, the meter showed a reading of 0.34, which is because the plane was closer to the radiation of outer space.

Every year, just walking around the planet, each individual is exposed to about 3.5 millisieverts of radiation. That's about 67 chest X-rays, or 134 cross- country plane trips.

Here is a comparison of the radiation levels of everyday items and activities:

Banana: .0007 mSv

Pistachio: .001 mSv

Smoke Detector: .0029 mSv

Abdominal CT Scan: 10 mSv

In the course of a year, a flight crew flying between Tokyo and New York is exposed to 14 mSv of radiation.