The spray program conducted at the Nuclear Safety Pilot Plant in 1967–1970 is summarized. Sprays have been proposed as a means for removing fission products from reactor containment building atmospheres following a loss-of-coolant accident. The problem was dealt with in three parts: removal of elemental iodine, removal of organic iodides, and removal of particles. Thirty iodine removal experiments were performed using borax, borax plus thiosulfate, and boric acid. Both borax and borax-thiosulfate were highly effective in removing elemental iodine. Boric acid is much more effective than expected. Fifteen methyl iodide removal experiments were performed. Only borax-thiosulfate at elevated temperatures removed methyl iodide at a significant rate. Extrapolation of the data to a large PWR indicates the dose reduction factor would be 1.1 for the flow, drop size, and reagent concentration normally specified. This can be improved by increasing flow and/or concentration or by reducing drop size. Fifteen particle removal experiments have been done. These show that phenomena associated with steam condensation make the major contribution to removing particles. The results indicate that sprays will remove particles effectively.