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Radioactive Decay Calculator
This online calculator computes radioactive decay, timed decay, and timed solid disposal for a databank containing 116 isotopes. It also features University of British Columbia disposal limits and a unit converter and date/time calculators. These tools calculate the half-life for selected isotopes; radioactive decay final activity, given the initial activity and decay time; the decay time, given the initial and final activities; and the decay time, given the mass of a solid and the initial activity.
Intended for grade levels:
  • High (9-12)
  • College (13-14)
  • College (15-16)
  • Graduate / Professional
Type of resource:
  • Tools:
    • Calculation / Conversion
  • Chemistry
  • Physics
Technical requirements:
No specific technical requirements, just a browser required
Cost / Copyright:
No cost
The Radioactive Decay Calculator was created and developed by Alan Enns. Copyright 1997 - 2002. Please do not copy without permission from the author.
DLESE Catalog ID: DLESE-000-000-004-088
Resource contact / Creator / Publisher:
Author: Alan Enns
No institutional affiliation

Contact: Maria Pylaeva
Health, Safety, and Environment
University of British Columbia