Chromium-51

Cr-51

 Half Life: 27.7 days

Radiation: EC, Gamma

Energy:
Gamma: 0.32 Mev (9.8%)
X-rays: 0.005 Mev (22.3%)
Auger Electron: 0.004 Mev (66.9%)

 Half-value layer for lead = 1.7 mm

ALI: 20 mCi

DAC: 8E-6 uCi/mL
Hazard: The hazard from Cr-51 is from both external and internal exposure. External exposure from a 1 mCi point source of Cr-51 at 1 meter is 180 mR/hr. Internally insoluble compounds can deposit in the lung, the critical organ. The lower large intestine is the critical organ for an intake of soluble compounds.
Safety Precautions:
  • Follow General Precautions for working with radioactive material.
  • Store in shielded containers.
  • Wholebody and ring badges are required for work with Cr-51.
  • Minimize exposure with lead shielding.
  • Use GM detector or liquid scintillation counter to detect Cr-51.
  • Urinanalysis is required within 24 hours after working with 100 mCi or greater of Cr-51.
  • Dispose of radioactive waste in accordance with requirements in Appendix G of the Radiation Safety Manual.

H-3, C-14, S-35, P-32, I-125, Cr-51, Tc-99m, P-33

Radiation Safety