High-Risk Departments

There are departments at the Medical Center where there is a greater likelihood of radiation exposure.  Pay close attention to warning signs on doors so you are aware of the hazards beyond.  Many departments have radiation-producing machines and radioactive materials, and it is helpful to be aware of the hazards.


Radiology has many radiation-producing machines, some portable and some permanently positioned.  Avoid going into rooms with the "Caution X-ray" sign during procedures unless you are involved in the case.  Confirm with the equipment operator if it is safe to enter.  If you’re involved in a case using x-ray, remember to wear lead protective garments and personal dosimeters when x-rays are generated.  Note that there is no radiation risk when the x-ray is off.

Some cases involve injected radioactive material.  Only staff trained in the risks should be involved in these cases.  To prevent spread of the radioactive material, wear appropriate personal protective equipment (gloves, shoe covers, and gown or scrubs).  When exiting a potentially contaminated area, allow the Nuclear Medicine technician or Radiation Safety staff to survey you with an appropriate meter.

Nuclear Medicine

Nuclear Medicine patients either ingest or are injected with radioactive material.  Avoid going into rooms with a “Caution Radioactive Material” sign without first checking with a Nuclear Medicine Technician. 

Nuclear Medicine patients become radioactive for a time, and the radiation cannot be turned off like x-ray machines.  The radiation gradually goes away at a rate dependent on the half-life of the particular radioactive material.  For a short time during and after a procedure, avoid being next to a Nuclear Medicine patient unless you need to be there to assist them.

Pregnant staff should not be working with Nuclear Medicine patients without first personally consulting with Radiation Safety.

Radiation Oncology

Cancer therapies can involve very high doses of radiation.  Pay close attention to the “Caution X-ray”, “Caution Radioactive Material”, and other signs warning you not to enter a room during a therapy.  These rooms are very well shielded to contain the radiation within the room. 

Some radiotherapies involve radioactive seeds implanted in a tumor.  The precautions when working around these patients should be posted on the entrance to their room.  Be aware of the precautions before entering.

Operating Room

X-ray, CT, and Fluoroscopy use is very common in the OR.  If you are in a case when radiation is being used, be sure to wear lead protective garments and a personal dosimeter to record your radiation exposure. 

Fluoroscopic and interventional cases must have a physician with a Fluoroscopy Supervisor/Operator permit present in the room while radiation is generated. 

A mobile radiation therapy unit (such as the Mobetron) may be brought in for an OR case.  Keep outside the barriers/signs positioned by the medical physicist during these therapies in order to protect yourself from this high dose radiation.

Some radioactive materials may be used during a case.  Follow the precautions of the Nuclear Medicine Technicians or Medical Physicists, and allow them to survey you and the area to ensure there is no radioactive contamination.

Outpatient medical and dental clinics

Many outpatient clinics have x-ray machines of various types.  Be aware of the “Caution X-ray” signs and only be involved in x-ray procedures if you have been properly trained.

Some clinics use radioactive materials.  Follow the same precautions as the Nuclear Medicine department.




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