Another Lawsuit

[Alex Zapantis <a.zapantis@qut.edu.au>]

Here in Queensland, Australia, the state Health Department has a number of
large caravans which are fully fitted out as mobile dental clinics. They
include one dental x-ray unit each and travel around the state to schools
performing free dental work on kiddies.

A dental nurse who worked in one of these vans developed thyroid cancer. She
sued the Health Department claiming that exposure to radiation from the
dental x-ray unit caused the cancer. No radiation shielding was installed in
the vans to protect the operator. The low workload and distance between the
tube and the operator were considered enough to keep exposures to trivial
levels. I believe that she was not issued with a dosimeter because,
dosimeters issued to dentists in "real" practices always returned an MDL
result. (Please correct me if I'm wrong Mike W. It's been a while!!). All of
the above complied with the requirements of the State Regulatory Authority
where I was employed at the time.

Myself and another physicist from the regulatory authority estimated the
maximum dose she could have received by radiographing a Rando head phantom
(many times!!) in one of the dental caravans and measuring the scattered and
leakage radiation at the place where the operator would stand. We used a
Farmer exposure meter and a "big" ionization chamber and worst case
geometry, exposure factors etc. I can't remember what the dose was (it was
measureable) but it was TRULY small, much less than 1mSv per year absolute
maximum.

The Health Department settled out of court. I don't know how much for...

Regards
 
  Alex Zapantis                                         
  Radiation Safety Officer                                     
  Queensland University of Technology 
  Acting Manager       
  Health & Safety Section                             
  Victoria Park Road                 Ph     : 61 7 3864 3566
  Kelvin Grove Qld 4059             fax     : 61 7 3864 3993
  AUSTRALIA                           Email  : a.zapantis@qut.edu.au    

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    "From the moment I could talk I was ordered to listen."

                                                               Cat Stevens

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