Protection Measures for Staff

As Low As Reasonably Achievable (ALARA)

• Aimed at limiting radiation exposure to radiation workers
  • Does not include Background (3.1 mSv) or Man-made (3.1 mSv) doses
• Dental workers’ occupational exposure is very low vs. other radiation workers
  • Reported doses are 0.04 mSv
  • Personal dosimeters not required (verify with state regulations)

ALARA Principles

• Time
  • Dose decreases linearly – decrease time by ½, decrease dose by ½
• Distance
  • Dose governed by “Inverse Square Law”
    • Increase distance by a factor of 2, decrease dose by factor of 4
• Shielding
  • Stand behind walls, leaded barriers, backscatter shields, etc.
  • If not available, staff should:
    • Wear lead apron
    • Stand at 45 degrees from the primary beam exiting patient’s head

Handheld X-ray Devices

• Hold the device at mid-torso height
• Ensure backscatter shielding ring is:
  • Oriented parallel to operator
  • Positioned at end of Position Indicating Device (PID)
• If operated without a backscatter shielding ring, the operator should wear a lead apron!
• Examples of devices:
  • KaVo NOMAD
  • Vatech EzRay