A critical evaluation was made of the experimental data regarding the rate of tritiated water formation. The evaluation tested the validity of the rate expression shown in Eq. 1. The experimental data does not appear to support the use of this rate expression for predicting tritiated water formation rates over wide ranges of initial tritium concentrations and large spans of reaction times. Modeling results are discussed which indicate the complexity of the tritiated water formation mechanism. The simplicity of Eq. 1 can not express the effects of the mechanistic complexity on the rate.