When an accident occurs at a
nuclear reactor, which of the following is the main health risk for people living
far away from the nuclear reactor? (A) Nuclear radiation escaping from
the reactor. (B) Sources of nuclear radiation
escaping from the reactor.
Our two answer options might seem
similar, but there’s an important difference between them. Say that we have a source of
nuclear radiation. This could be a chunk of
radioactive material like uranium or plutonium. This source gives off
radiation. The source and the radiation are
two separate things. In this example, we’re imagining an
accident at a nuclear reactor. So let’s say that here is our
reactor that has had an accident, say, by a hole being opened up in the reactor. We want to know what is the main
health risk for people living far away.
During normal operation, a nuclear
reactor contains radioactive material. The reactor is designed to shield
this material from spreading as well as block the radiation it gives off. If a hole was opened in the wall of
the reactor, two different things could escape: first, nuclear radiation, what is
given off by the radiation source. It’s also possible, though, that
the source of the radiation itself could be released from the reactor.
For people living far away from the
reactor, the radiation by itself escaping would not pose a significant health
risk. That’s because it has to travel
such a long distance that by the time it reached these people, it would not be very
harmful. However, if the sources of
radiation themselves were projected out of the reactor, these could then give off
radiation at a much closer distance to the people concerned. So it’s the sources escaping from
the reactor that is more dangerous than the radiation itself. We choose answer option (B).