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24 May 2012

Answer to Question #802 Submitted to "Ask the Experts"

Category: Radiation Basics — Radiation Shielding

The following question was answered by an expert in the appropriate field:

What is the half value thickness (HVT) and tenth value thickness (TVT) of lead and stainless steel for the energy 141KeV (^99mTc)? Is there any mathematical relation between energy and HVT, TVT?

It was assumed that the question pertains to exposure-rate calculations, so absorption coefficients were used to calculate the following: Material: Steel HVL (cm): 1.0 TVL (cm): 3.4 Material: Lead (Pb) HVL (cm): 0.03 TVL (cm): 0.1 A single mathematical correlation does not exist between these quantities since scatter and adsorption probabilities vary significantly with energy and material type.

Robert L. Coleman
Oak Ridge National Laboratory

Answer posted on 27 March 2001. The information and material posted on this website is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Website. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.