RADIATION   SAFETY Proper safety precautions must be observed by all persons working in or near an area where X-rays are being generated. X-rays can be dangerous. Long term overexposure  to  radiation  may  result  in  loss  of  hair, redness  and  inflammation  of  the  skin,  blood  count change,  cell  atrophy  (wasting  away),  ulcerations, sterility, genetic damage, cancer, leukemia, and death. There are safety measures designed to protect the patient  and  the  health  care  team  from  the  dangers  of overexposure  to  radiation  and  the  operation  of  X-ray equipment.  You  must  observe  these  safety  measures when working in radiology. Your command will have instructions and standard operating procedures (SOP) for the operation of dental radiographic (X-ray) units and  equipment.  You  will  be  required  to  read  these procedures if you are newly assigned to the radiology department. There are other numerous responsibilities that  include  providing  radiology  support  for  oral diagnosis,  log  maintenance,  infection  control,  testing for quality control, and processor maintenance. PATIENT  PROTECTION A number of precautions are taken to prevent the patient from being exposed to inappropriate diagnostic radiation. The decision to order dental radiographs is determined by the dental officer on a case by case basis for each patient. Only a dental officer is authorized to order and diagnostically interpret dental radiographs. Perhaps the most important safety measure is the responsibility   of   the   assistant:   When  taking radiographs, you should always have patients wear lead   aprons   and   thyroid   collars   to   shield   their reproductive  organs  and  thyroid  glands.  There  is only  one  exception  to  this  rule;  when  obtaining  a panorex radiograph, the thyroid collar is not used since it blocks part of the X-ray beam. In addition, always  ask  a  female  patient  whether  or  not  she  is pregnant or if pregnancy is questionable, before taking radiographs.  If  she  is  pregnant,  consult  the  dental officer. Other   radiation   safety   measures   include   X-ray machines  that  have  built-in  safeguards  that  filter  out harmful radiation and restrict the central X-ray to the smallest  possible  area.  Fast  film  is  used  to  shorten expos  ure  time;  and  only  essential  radiographs  are taken on patients. Figure 1-1.—Environmental dosimetry radiation film badge. ASSISTANT  PROTECTION When  you  work  near  a  source  of  radiation,  your X-ray  department  will  be  issued  an  environmental dosimetry radiation film badge (fig. 1-1). feet from the tube head and never in the direct line of radiation  during  expos  ure.  These  film  badges Appropriately  placed  environmental  film badges  are  used  to  monitor  stray  radiation  that  may occur  in  and  around  the  X-ray  department.  The badges  are  placed  in  the  X-ray  room  behind  the technicians  protective  lead-lined  barrier  or  at  least  6 contain  X-ray  sensitive  film  in  a  light-tight  packet. The  film  packets  are  collected  every  6  to  7  weeks. After   collection,   the   film   is   sent   to   the   radiation detection  laboratory  for  processing  and  evaluation. Any  abnormally  high  readings  (i.e.,  greater  than 0.010   REM   [Radiological   Equivalent   Mammel]) shall  be  referred  to  the  Radiation  Health  Office  for investigation. When you take radiographs on a patient, observe the  following  precautions  to  avoid  unnecessary exposure to radiation: NEVER stand in the path of the central X-ray beam  during  exposure. NEVER  hold  the  X-ray  film  packet  in  the patient's mouth during exposure. NEVER  hold  the  tube  head  or  the  tube  head cylinder of the X-ray machine during exposure. ALWAYS   stand   behind   a   lead-lined   screen during  an  exposure. X-RAY FILM LOG Another  portion  of  radiation  safety  is  to  account for  all  radiographs  that  are  taken.  An  X-ray  film  log 1-2