In recent years, under the limited information that the means and variances of the failure and repair times are just given, the method of evaluating MTTF in the two-component standby redundancy system with priority has been proposed. In this study, by expanding the idea to evaluate MTTF proposed in the previous research, an evaluation method for the variance of the failure times in the aforementioned system is established under the premise that the means and variances of the failure and repair times are just given. Through numerical verification, the usefulness of the evaluation method constructed in this study is reconfirmed.
