Eight large-scale spray experiments have been made in the 26 500 ft3 Containment Systems Experiment (CSE) vessel. In each experiment a major parameter was changed. Spray fluxes ranged from 0.025 to 0.3 gal/(min ft2). Spray drop size was 770- or 1210-µm mass median diameter (MMD). Atmospheric condition was air at room temperature and pressure or steam-air initially at 250°F, 48 psia. Three types of spray solutions were used: boric acid, pH 5; boric acid plus NaOH, pH 9.5; and boric acid plus 1 wt% Na2S2O3 with NaOH added to pH 9.5. The only major parameters not varied were the drop fall height (38 ft) and the gas-to-liquid volume ratio (∼80).