In the design of facilities which handle tritium, radiation safety assessments for various operational parameters and conditions are required. A computer-based system, entitled RAPTIAH, has been developed which performs the analyses and provides the fundamental information required for such assessment. RAPTIAH starts by estimating fluid leak rates from individual components. From the leak rates it derives the rate of tritium release in each area of the facility. Next, the airborne tritium concentrations in areas of the facility and the release of tritium to the environment are obtained. Finally, using component reliability data and the pattern of maintenance, the potential tritium exposure to occupational individuals is estimated. RAPTIAH may be used to identify design measures which would enhance radiation protection in tritium handling facilities.