Science Notebook: On the Mind of a Modern Day Health Physicist

About the Author: Mike Boyd joined EPA in 1988 as a health physicist in what is now the Office of Radiation and Indoor Air. Health physics is the profession of radiation protection. Mike’s work at EPA focuses on radiation risk assessment.  He helps develop federal guidance, the rules and regulations that protect the American public from the harmful effects of radiation.

image of author sittingHealth physics is a term most people don’t understand. People often guess that my job has something to do with physical therapy. Actually, the term was coined during the Manhattan Project – a national effort to develop the first atomic weapon during World War II.

There are several stories about how the term originated. I like the one that says that “health physics” was chosen over “radiation protection” because it “conveyed nothing.” The Manhattan Project was very secretive, so a name that disguised any association with radiation would be appropriate. I imagine someone in charge saying, “Some of you physicists need to design the protective shielding for this project and some of you need to monitor worker exposure. Raise your hand if you want to be our health physicists.” Maybe it didn’t happen just that way, but it could have!

As fascinated as I am by the challenges facing these first health physicists, their work has little resemblance to what I do today with EPA. Radioactive elements are commonly found in nature. Since there is no such thing as “zero radiation,” how do we determine how safe is “safe” and how clean is “clean?” These are the questions I deal with.

This raises an interesting question. After a radiological emergency, should “clean” be a constant, or should it depend on a larger context? Is “clean” the same for a major nuclear incident in a large city as for a small scale event in a rural area? What if it means abandoning a city? Will people accept an increased lifetime cancer risk to be able to get back to their homes and livelihood? There is no easy answer.

Chernobyl teaches us that some people will try to go back home no matter what the radiation levels and risks. Others will stay away, no matter how low the levels eventually reach. My personal opinion is that it is best to approach such situations on a case-by-case basis, hoping, of course, that there is never even one such case. We have benchmarks to begin the process of determining clean-up levels, including the history of what was achieved at radiation-contaminated sites around the country.

We cannot know in advance what emergency managers may face in the future, but we know that no decision regarding cleanup will mean anything without serious public involvement. These are just some thoughts of one EPA health physicist. I’d like to hear what you think!

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