RADIATION SAFETY CASE STUDY ASSESSMENTS
35 pts
A. Read the following report of a laboratory accident involving radioactivity.
Consider what actions, or inactions, on the part of the involved parties contributed
to the accident or made the accident worse. List 4 things that should have been
done that could have either prevented the accident, or decreased its severity.
Steve Jones, a graduate student at UC Southridge, was irradiating a sample with a
laboratory source that emitted gamma rays. The source was a radioactive sample that
was suspended on the edge of a clamp. The lab sample was a beaker of cells. He
lowered the source into the cells, waited the appropriate length of time, and then raised
the source. He kept a radiation monitor on the entire time next to his workspace to
monitor the experiment. Following the removal of the source equipment, he moved his
beaker of cells to a water bath in another lab (the Houser Lab) so they could incubate at a
higher temperature. When he returned to remove his cells, he noticed that his beaker had
cracked, probably due to an aggravation of a small crack by the high temperature in the
water bath. Tired and aggravated, he left a note on the water bath indicating that he
would come clean it up the next day. He then went home. A few hours later, Diane
Vitale, the researcher who was working at the lab bench which housed the water bath
began to feel ill. Suspecting nothing, she too went home. Finally, three hours after Steve
had first taken his cells into the Houser lab, a third researcher, Beth Johnson, began a
radioactive experiment of her own. However, as she turned on her radiation monitor at
the start of her experiment, she was disturbed by the very high readings she was picking
up. Suspecting that something was wrong, she used her monitor to localize the source,
and traced it to the out-of-commission water bath. She immediately called Steve Jones at
home to find out what had happened. Steve agreed to come back in, although he still felt
poorly, and soon Beth and Steve pieced together that the source he had used to irradiate
his cells had come loose from its clamp and fallen into his beaker of cells. Two hours
later, now five hours after the source had come loose, Radiation Safety declared the two
labs fit for work. Steve Jones, Diane Vitale and Dr. Roman Bell, who worked in an
office adjoining the Houser Lab and who had been in and out of his office numerous
times within that five hour period, were all treated for radiation exposure and released.
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B. Read the following description of a case involving radioactive contamination.
Provide a scenario that explains how the various areas of contamination occurred.
Dr. Tyler Maxwell, a researcher in the Strassman Lab at the Carolina Institute, is
finishing up his experiment. He has been doing some protein work which involves using
an alpha emitter. To monitor his workspace for contamination when he is finished, he
performs a wipe test. This means that he wets a Kimwipe with some water from his
squirt bottle and swabs various areas of his workspace. He inserts the swabs into liquid
scintillation vials and then takes them to the liquid scintillation counter to read his
samples. He sees no contamination in any of his samples. Done for the day, he closes up
his laboratory and heads home. Later in the day, Lori Davidson, a graduate student
working in the Strassman Lab comes in to start her experiments. She does her work,
cleans up her workspace using Dr. Maxwell’s squirt bottle, and, neglecting to wash her
hands, shuts out the light and closes the door. The next day, David Sanchez, a technician
in the Strassman lab, is working with a beta emitter. In the middle of his experiment, he
is interrupted by a phone call. Because it is from his son’s teacher, he decides to take the
phone call. He monitors his gloves, sees they are slightly contaminated, and discards
them. He talks on the phone for several minutes and then returns to work. At the end of
his experiments, he monitors his work area, which is clean, and then himself. He finds
low-level radiation on his hands and in his hair. Knowing that he NEVER touches his
hair or face while working in the lab, he calls for help. After getting help washing his
hair out, he decides to monitor the lab with a Geiger counter and then perform a wipe test
to be sure low level contamination is not present. He finds the following areas of
contamination:
Location
Phone
David’s hair
David’s hands
Table on which phone sits
Door handle
Light switch
Lori’s pencil
Dr. Maxwell’s water bottle
Type of radioactivity
Beta emitter
Beta emitter
Beta emitter
Alpha and beta emitters
Alpha emitter
Alpha emitter
Alpha emitter
Alpha emitter
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