Radioactive Decay: Concepts and Mathematics

This tutorial provides 2 CEUs and is ideal for:

    1. Nuclear Medicine and Radiology Technologists. The VOICE program of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) has reviewed this program and approved it for a maximum of 81 continuing education hours. Because these tutorials have been approved by the VOICE Program, they are accepted for CE credit in all 50 states and by ARRT and NMTCB, even if you are not a VOICE/SNMMI member.
    2. Physicians requiring CME Credits to maintain IAC Accreditation. All or a portion of this educational activity may meet the CME requirement for IAC Nuclear/PET Accreditation. Our website is listed on the resources page of the IAC website.

Proceed to the Tutorial: Radioactive Decay Tutorial

Proceed to the Quiz: Radioactive Decay Quiz

Purchase Tutorial: Payment link (Credit Cards/Paypal)IMG_4367RADIOACTIVE DECAY:  2 CEU This tutorial gives an overview on Interaction of Ionizing Radiation With Matter

Objectives for Tutorial on Concepts and Mathematics of Radioactive Decay

Topics to be Covered:

  1. Definition of radioactive decay, the exponential law that it follows, and a definition of half-life.
  2. Graphic representation of radioactive decay as a function of time, both prospectively and retrospectively
  3. The classic mathematical formula for radioactive decay and a more modern formula with its increased simplicity.
  4. Mathematical problem solving
  5. Bi-exponential decay and graphical analysis

After completion of this tutorial, one should be able to:

  1. Define radioactive decay and half-life.
  1. Explain what happens to activity of a source going prospectively and retrospectively in time, that is, half-lives from now and half-lives in the past
  1. Using graphical analysis, determine half-life from a semi-logarithmic plot of activity vs time.
  1. State mathematical relationship between l (the decay constant) and the half-life and compare to the mathematical relationship between m (the linear absorption coefficient) and the half-value layer.
  1. Write the equations for calculations involving activity decrease as a function of the number of half-lives
  1. Work a variety of math problems involving change of beam intensity with change of number of HVLs or TVLs.

If you have taken one of the tutorials, received a score of 80% or above, and wish to receive CE credit: Make sure you submit all of the requested information when taking the test. It’s not necessary to send us the score sheets since we receive them electronically when you submit your answers for scoring.Within 24 hours of receipt of your submitted score sheets and payment for the tutorial(s), we will do all of the following:1. Send a certificate to you via e-mail
2. Send a certificate to you via US Mail
3. All members of the SNMMI will have to self-report their CE Credits on the SNMMI Website ( We will automatically send detailed self-reporting instructions to you along with your CE Credit Certificate.
If you have any problems with the self-reporting system, please contact the VOICE Coordinator directly at 703 708-9000. ).If paying by check, please make payable to Consultants in Nuclear Medicine and mail your payment to:   Consultants in Nuclear Medicine 2910 W. Estes Avenue  Chicago, IL 60645-2394To make sure your check is in the appropriate amount, please note the following:
If a tutorial awards 1 CEU, the cost is $20.00
If a tutorial awards 2 CEU, the cost is $30.00
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If the score is still <80%, please contact Dr. Karesh, Tutorials Coordinator, by e-mail at for further instructions.