Dealing with hazardous environments such as hydrogen poses considerable risks to property, people, and the environment. Leak frequency analysis is a method of understanding the characteristics of risks at hydrogen refueling stations (HRSs). This paper proposes leak rate estimation using time-based evaluation methods that utilize historical HRS accident information. In addition, leak frequency estimates from another two methods (non-parametric and leak-hole-size) were examined. In the non-parametric approach, the leak frequency is estimated based on a Bayesian update. The results from these three approaches are summarized to understand the trend of leak rate data. The leak rate data from the time-based method displays a similar trend to the leak size based method. However, the non-parametric method tends to be conservative due to high failure observations (new evidences) during the Bayesian update. Finally, the unrevealed leak time was calculated as a function of the leak frequency. The quantitative insights of this study can be used to set performance standards for the availability and reliability in the operation and maintenance of HRSs. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.