The University of Iowa

Radionuclide Safety Guideline for C-14

Physical Data

  • Radiation: Beta (100 % abundance)
  • Energy: Max: 156 keV; Average: 49 keV


  • Physical: 5730 years
  • Biological: 12 days
  • Effective: Bound - 12 days; unbound; 40 days


  • 24 cm in air unshielded

External Hazard

  • Not an external Hazard

Internal Hazard

  • Critical Organ: Fat tissue

Skin & Eye Hazard

  • Can deliver a contact dose to basal skin cells and eye lens of about 1,400 mrem/hour per 1 uCi per 1 cm2.

Safety Guidelines

  • Plexiglas 1 cm thick is recommended as shielding material. Thinner Plexiglas, although adequate to reduce exposure, does not have good mechanical properties.
  • Dosimeters cannot detect C-14 beta radiation due to its low energy.
  • Wear a lab coat and disposable gloves when working with C-14. Change gloves frequently.
  • Avoid direct eye contact - work behind a Plexiglas shield or wear safety glasses.
  • 14C-labeled halogenated acids may be incorporated into the skin.
  • Procedures involving the release of 14C-labeled CO2 must be conducted in a fume hood or within a sealed chamber vented to a suitable filter trap. Contact EHS at 335-8501 for further information.

updated 01/2013