Radionuclide Safety Guideline for H-3
Physical Data
- Radiation - Beta (100% abundance)
- Energy - Max: 18.6 keV; Average: 5.7 keV
Half-Life
- Physical: 12.3 years
- Biological: 10-12 days
- Effective: 10- 12 days
Range
- 6.0 mm in air unshielded (0.5 cm; 0.25 inches)
External Hazard
- Not an external hazard
Internal Hazard
- Critical Organ: Body water or tissue
Skin & Eye Hazard
- 0% of H-3 beta particle energy is transmitted through the dead layer of skin.
Safety Guidelines
- Shielding is not required. Dosimeters cannot detect H-3 beta radiation due to its low energy.
- H-3 cannot be detected with a survey instrument or with a dosimeter.
- Wear a lab coat and disposable gloves when working with H-3. Change gloves frequently.
- Avoid direct eye contact - work behind a Plexiglas shield or wear safety glasses.
- Skin contamination, inhalation, ingestion or absorption through the skin is assumed to be completely and instantaneously absorbed and rapidly mixed with total body water.
- Volatile H-3 compounds should be used in an operating fume hood. Contact Laurie Scholl at 353-5389 for further information.
- Tritiated water can readily penetrate gloves and skin in a short period of time.
- DNA precursors are more toxic than tritiated water because the activity is concentrated in the cell nuclei.
- Bioassays are required following the use of 100 mCi or more of tritiated water or 25 mCi or more of organically bound H-3.
updated 1/2013