An analytical method based on the steady-state release model developed by Idaho Nuclear Corporation (now Aerojet Nuclear Company) is presented for calculating noble gas and iodine release to the fuel cladding gap of fuel pins in a nuclear reactor operating at steady-state conditions. This method, which employs fission gas capsule data and conservative assumptions (assumptions that result in prediction of maximum release), can be used in reactor safety analysis to predict the fission gases that could be available for release in the event of cladding failure and the pressure exerted by the fission gases on the inside of the cladding during reactor operation.