Conversion factors and half-life information for radioactivity.

Discussion of radioactivity may use different terms for measurements of radioactivity and dose. Conversion factors for these terms are presented in this appendix. In addition, when investigators are working with a particular radiolabeled compound, it is necessary to calculate the amount of remaining radioactivity based on the amount of time that has elapsed from the reference date and the half life of the radioisotope. Decay factors for the commonly used shorter half life radioisotopes are provided here.