Abstract: A dry, water-soluble biocidal composition comprises (a) 0.01 to 5 parts by weight of water-soluble inorganic halide, (b) 25 to 60 parts by weight of an oxidizing agent which, in aqueous solution, reacts with the halide to generate hypohalite ions, (c) 3 to 8 parts by weight of sulfamic acid, (d) 0 to 20 parts by weight of a non-reducing organic acid, (e) 10 to 30 parts by weight of an anhydrous alkali metal phosphate, the parts by weight of the composition totaling 100, the pH of a 1% by weight aqueous solution of the composition being between 1.2 and 5.5, and the composition being characterized by lack of evolution of halogen at a pH less than 3.0 and a biocidal activity substantially greater than that produced by like compositions having inorganic halide concentrations greater than about 20%.

Abstract: A method of disinfecting premises from coccidial oocysts in which surface to be disinfected is thoroughly wetted with a first aqueous solution of ammonium salt containing approximately 0.5 to 1.5 molar of ammonium together with non-ionic surfactant and indicator having a color change in the region of pH 8 to pH 10 and the wetted surface is then covered with sufficient of a second aqueous solution of alkali metal hydroxide containing approximately 0.75 to 2.3 molar of hydroxide toether with phenolic bactericide to cause the indicator to change color on the treated surface. A preparation for use in such a method comprises a first package containing ammonium salt together with non-ionic surfactant and indicator and second package containing alkali metal hydroxide and phenolic bactericide, the molar amount of hydroxide in the second package being greater than the molar amount of ammonium in the first package.