(CA-45) - Physical Data

Pure Beta Emitter:
  • Beta Energy
    • 258 keV (max.)
    • 77.2 keV (avg.)
  • Radioactive Half-Life
    • 162.61 days
  • Effective Half-Life
    • 162 days
  • Biological Half-Life
    • 1.8 x 104 days
  • Max. beta range in air
    • 47.91 cm
  • Approximately 50% transmission rate through dead layer of skin  
Radiological Data:
  • Critical organ: bone
  • Internal exposure through ingestion, inhalation, or absorption are primary concerns
  • Dose rate to the basal cells from skin contamination is approx. 2850 mr/hr µCi per cm2
Shielding:
  • None required
Survey Instrumentation:
  • Liquid Scintillation Counter (LSC)
    • LS window:  0 to 750
    • LS efficiency:  100%
  • Geiger - Mueller counter (efficiency low) 
Regulatory Compliance:
  • ALI
    • 2000 µCi: (by ingestion)
    • 8000 µCi:  (by inhalation)
  • DAC
    • 4 x 10 -7 µCi/mL
Special Considerations:

In general, Calcium-45 does not require any special precautions over and above those necessary for any beta-emitting radionuclide of this energy of emissions.  The majority of Calcium-45 is deposited in the bone and is retained with a long biological half-life.