[en] Test results for Part I of the ¹/₄-Scale Pressure Suppression Pool Swell Test Program are presented together with an evaluation of the hydrodynamic scaling laws. The scaling laws provide for experimental modeling of the pool swell phenomenon that would result from a postulated Loss-of-Coolant Accident (LOCA). Twenty-four tests were performed in the ¹/₄-Scale Test Facility. Two conditions of both drywell pressurization rate and initial drywell/wetwell differential pressure (ΔP) were tested. Data from these tests were compared with data from earlier tests in the ¹/₁₂ Scale Test Facility, which is geometrically similar to the ¹/₄ Scale Test Facility. Comparisons of the ¹/₁₂ and ¹/₄ scale data, related on the basis of the hydrodynamic scaling laws, indicate a high degree of similitude and thus provide experimental verification of the scaling laws. The sole restriction in regard to the confirmation of the scaling laws is the downforce for which scaling has been confirmed only at the full ΔP test condition