We have determined the half-life of I samples to be 7.969 +0.014 day under conditions in which the radiations of 12.0-day '3'"Xe are not detected, and to be 8.117+0.012 day under conditions in which the radiations of 3 Xe are detected. Furthermore, we have seen no variations of half-life due to the physical state of the source to within 0.3Vo. We believe that these data indicate the half-life variations for I reported by Bergamini et al. and Kemeny may be accounted for by the escape of daughter~3~~X e and/or absorbtion of the radiations of '"~Xe.