Understand units and concepts of occupational radiation exposure.
Discuss methods for reducing exposure.
Explain positioning of occupational radiation monitors.
Discuss personnel radiation monitoring reports.
List available thicknesses of protective apparel.
Exposure Categories:
Average whole-body dose: 0.7 mSv/yr.
53% receive less than minimum detectable dose.
88% receive <1 mSv/yr.
0.05% receive >50 mSv/yr.
Radiation Dose Measurement:
Measured in Gyt (rads) for dose, Gya (roentgens) for exposure.
Rem for radiologic technologists and radiologists' exposure.
Effective dose (Sv) for radiation protection.
Occupational Exposure Limits:
Recommended dose limit: 0.5 Sv/yr (5000 mrem/yr).
For general x-ray activity: max 1 mSv/yr (100 mrem/yr).
Highest exposure during fluoroscopy.
Relation of personnel exposure to x-ray beam-on time.
Mobile Radiography:
Use of protective aprons and exposure cords to maintain distance.
Formula: Exposure = Exposure rate × Time.
Example:
2.5 Gya/hr × 2.5 minutes = 0.1 mGya.
Higher exposure due to longer beam-on times.
Importance of extremity monitoring.
Low personnel exposure due to low kVp, resulting in less scatter.
Use of barriers in dedicated mammography units.
Low exposure levels, mainly secondary radiation.
Monitoring procedures required during imaging.
Minimal occupational exposure among surgical staff.
PPE and monitoring are crucial in mobile radiography settings.
Whole-body dose limits established by NCRP.
MPD concept replaced by annual cumulative dose limits.
Recent recommendations address specific organ exposures.
Must be worn during fluoroscopy and mobile radiography.
Different thicknesses: 0.25, 0.5, and 1 mm of lead equivalent.
Maximum exposure reduction with 1 mm lead equivalent, though heavy.
Required for individuals at risk of receiving >1/10 the dose limit.
Types of personnel monitors: film badges, TLDs, OSLs.
Film Badges: traditional and sensitive to temperature/humidity.
TLDs: more accurate, no loss of information.
OSLs: increased sensitivity and accuracy.
Monitoring reports to include current and cumulative exposure.
Coordination of monitoring transfer when changing employment.
During Imaging:
Maintain distance and utilize protective measures.
Follow ALARA (As Low As Reasonably Achievable) principles.
Notify supervisor upon pregnancy declaration, with dose limits adjusted.
Emphasis on minimizing exposure with secondary monitors.
Incorporate robust training for new and existing employees on radiation safety.
Encourage regular in-service training sessions focusing on radiation exposure and safety protocols.