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Common Questions About Radiation

Dosimetry


Q:  Who should wear a film badge?
A:  All individuals whose work is associated with radiation who are likely to receive exposures above 10% of the limits stated in the Occupational Exposure Limit are required to wear a radiation dosimeter (above 5% of the limits for persons under 18 years of age).  This includes individuals who work with x rays and radioactive materials in Radiology, Radiation Oncology, Nuclear Medicine, Nuclear Cardiology, and anywhere where fluoroscopy is used.  Whole body badges and extremity badges are issued for a one-month wear cycle and are used to monitor exposure to X-ray and gamma-ray.

Q:  How can I get a radiation monitoring badge?
A:  In order to get a radiation monitoring badge you need to attend a Radiation Safety Training program.  Once completed you should receive the badge within a week.  You also need to do a yearly refresher thereafter.  If you change department or will no longer need to monitor your radiation exposure contact RSO at 5-0303 or email at badges@columbia.edu

Q:  How can I receive radiation safety training?
A: Radiation Safety training is offered at Morningside campus the first Tuesday of each month from 10 am to 12 noon. http://www.ehs.columbia.edu/TrainingSchedule.html

Q:  When radiation monitoring badges are distributed?
A:  Once you complete your radiation safety program your badge will be distributed on a monthly or quarterly basis.  At that time old badges will be returned.RSO (Radiation Safety Officer) reviews each monthly report; however, you will only be contacted if the reading is above certain limit. At the end of each calendar year, you will receive a report describing your radiation exposure the previous year. You have the right to request, in writing, to see your exposure history at any time.

Q:  Where should I wear a radiation monitoring badge?
A:  The whole body dosimeter should be worn on the area of the whole body (from the knee up and elbow up) most likely to receive the highest exposure (e.g. on the upper chest area) with the identification sticker facing forward. If lead aprons are worn, the badge should be clipped to the shirt collar or to the outside of the top of the lead apron to measure exposure to the eyes. Supplemental badges, if issued, may be worn under the lead apron but readings obtained from such badges do not accurately measure exposure to the eyes or thyroid.  Ring badges shall be worn on the dominant hand with the label facing in the direction that your hand will receive the highest radiation exposure. This badge must be protected from contamination; therefore, it must be worn under gloves when you are working with radioactive material.

Q:  Can I share my radiation monitoring badge with another individual?
A:  No, radiation monitoring badges are to be worn only by the individual to whom they are assigned to, and only during times when radiation exposure is due to your work duties.

Q:  How do I find out about my radiation exposure?
A:  Radiation monitoring records are maintained by the Radiation Safety Office and posted at your department. Monitored individuals are encouraged to view their radiation exposure readings.

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ALARA

Q:  What is meant by ALARA?
A:  In addition to providing a limit on a person’s annual radiation exposure, the regulatory agencies also requires that its licensees maintain occupational exposures to as low as reasonably achievable (ALARA) or as far below the limit as reasonably achievable.

Q:  How much radiation can I be exposed to?
A: The maximum radiation that you can be exposed to depends on your work duties and who you are.

If you are a minor between 16-18 years of age working at the hospital under close supervision, your allowed limit is 100 mrem per year.
If you are a declared pregnant worker your limit is 500 mrem from the date you declared your pregnancy.
The limit for a non-radiation worker is 100 mrem per year.  For a radiation worker is 5000 mrem per year.  For the general public is 100 mrem per year.

All of these limits exclude any radiation you may receive form background radiation or any medical you may undergo as a patient.

Q:  Who is a declared pregnant worker?
A:  A declared pregnant worker is a worker who declares her pregnancy to her supervisor and the Office of Radiation Safety. This declaration must be in writing and include the estimated date of conception. Pregnant radiation workers are encouraged to declare their pregnancy to their supervisor and the RSO. A special film badge will be issued and radiation exposure reports will be monitor closely.

Q:  How can I protect myself from external exposure?
A:  There are three effective ways to minimize your external radiation exposure:

Time:  The less time you spend with the radioactive material the less exposed you will be
Distance:  The further away for the radioactive source the less exposure you will receive
Shielding:  The use of an appropriate barrier will lower you exposure.

Q:  How can I apply for a license to use radioactive material?
A: Application for the use of radioactive material can be obtained from the Radiation Safety Office. The application will be reviewed by the Radiation Safety Officer and by the Radiation Safety Committee.

Q: How can I have my radioactive waste picked up?
A: Fill on line the radioactive waste pick up form EH&S webpage http://vesta.cumc.columbia.edu/ehs/radioactivewastepickup/.
The waste will be picked up within two to three business days.


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