Radiation safety

Exposure control

Time, distance and shielding

The following three principles are used to keep the exposure to radiation “as low as reasonably achievable” (ALARA).

• Minimize exposure time - Decrease the amount of time spent around a radioactive source. Quick Tip: “Dry” runs, in which no active materials are used, should be performed to master the particular technique
• Increase distance from the source - Increasing distance is one of the easiest methods of minimizing exposure
• Use shielding - The purpose of shielding is to ensure that workers are not exposed to radiation levels exceeding 2.5 µSv/hr. Consult the shielding requirements for information detailing what shielding to use in order to effectively limit your exposure
  

Lead Safety

The purpose of this "Safe Use of Lead Shielding" document is to protect the health of individuals working with and around lead sheets and bricks for radiation shielding within a laboratory setting.

Dosimetry

Personal dosimeters are issued  to measure  and record  the amount  of an occupational radiation dose an individual receives in the workplace as required by regulations.

It is mandatory to enroll in a dosimetry program where exposure calculations indicate a reasonable likelihood of radiation exposure.

Application for Radiation Badge

If you will be handling unsealed or sealed sources or using X-ray devices, you are required to obtain a radiation badge.

Personal exposure reports

Radiation safety staff maintain all records of internal and external monitoring in conjunction with the National Dosimetry Service. Personal exposure reports can be made available upon request. Please contact the Radiation Safety staff at ehs_rst@sfu.ca for further information.

Personal Monitoring Program

Pregnancy or planned pregnancy:

Should an authorized radiation worker become pregnant, special consideration must be made to ensure limited exposure to the embryo or fetus. Once a worker is aware of their pregnancy they are strongly encouraged to inform the Radiation Safety Officer (RSO) in writing. Upon disclosure of a pregnancy, the RSO will provide the following services:

• Consultation for the reassignment of work duties in order to minimize exposure, and adhere to the ALARA principle
• Additional radiation monitoring devices

For more information, please consult the Radiation Safety Manual, and visit the Pregnancy page.

External monitoring:

Consult the Badge Requirement Plan to determine whether or not your work requires personal radiation monitoring and if so, what kind of badge(s) you are required to use. 

Internal monitoring:

If you plan on working with volatile materials, such as radioiodine or intermediate levels of tritium, please contact the Radiation Safety staff.

Individuals working with radioiodines may need to undergo a thyroid bioassay. Those requiring a bioassay are to report to the Radiation Safety Technician or the Radiation Safety Officer to undergo a thyroid check prior to initiating work with radioiodines and then again during the interval if 24 hours – 5 days following an experiment involving work with radioiodine.

Individuals working with intermediate levels of Tritium may be required to collect urine samples for bioassays to determine their internal exposure. Please contact the Radiation Safety Technician for more information on urine sampling.