University of Maryland Baltimore
University of Maryland, Baltimore

home > radionuclides > chromium
Environmental Health and Safety
EHS Building


Related:
ALARA
Closeout Procedures
Dosimetry
Emergency Procedures
Forms
Laser Safety
Material Authorizations
Material Procurement
Policies and Procedures
Radionuclides
Safety Inspections
Safety Training
Sealed Sources
Waste Disposal
Worker Registry

Contact:
Environmental Health
  and Safety
714 W. Lombard Street
Baltimore, MD 21201
410-706-7055
Fax 410-706-8212

 
Chromium-51

Physical Data:

  • Principal mode of decay:  Electron capture

  • Principal emissions:

    Intensity
  • Gamma Energy
 320 keV 10.08%

x-ray

 5.2 keV 22.3%
  • Radioactive half-life
 27.7 days  
  • Biological half-life
 18 days total body
1000 days, bone		  

Radiological:

  • Critical organ:  bone (5%), liver (25%)

Dose rate:

  • 100 cm from 1µCi - 0.023 mr/hr
  • 10 cm from 1µCi - 2.3 mr/hr
  • 1 cm from 1µCi - 230 mr/hr

Shielding:

  • 1/4 in lead > 1µCi
  • 1/2 in lead > 10µCi

Survey Instrumentation:

  • NaI Scintillation Counter
  • Liquid Scintillation Counter (LSC)
    • LS window:  0 to 400
    • LS efficiency:  37%

Regulatory Compliance:

  • ALI
 40,000 µCi: (by ingestion)
50,000 µCi:  (by inhalation)
  • DAC
 2 x 10 -5 µCi/mL

Special Considerations:
In general, Chromium-51 does not require any special precautions over and above those necessary for any radionuclide of this energy of emissions.  Chromium-51 in the form of chromate is not selectively absorbed by any organ in the body.

top