A stabilised hypochlorous solution contained in a bottle impervious to light comprising: • hypochlorous acid (HOCI), • hypochlorite (ClO -), and • chlorine (Cl -), which species combined provide a total chlorine concentration, wherein the stabilised hypochlorous solution is obtained by careful stochiometric control of reactants water, calcium or sodium hypochlorite salt and phosphoric acid utilising: i) a source of de-ionised water having an electrical conductivity of no more than 50μScm-1 at 20°C; ii) a greater than 60% pure calcium or sodium hypochlorite salt; and iii) phosphoric acid, to adjust the pH to between 3.0 and 6.5: • the total chlorine concentration is at or below 300ppm; • the hypochlorous, measured by UV spectroscopy at 230nm, is the predominant species; • the hypochlorite, measured by UV spectroscopy at 290nm, is present at significantly lower levels than that of the hypochlorous, such that ratio of hypochlorous acid to hypochlorite is greater than 7.5:1, and • the solution has a pH of between about 7 and 4 and a shelf life of at least 12 months, at 22°C, such that the amount of hypochlorous present remains at above 80% of its starting concentration, and the pH remains above 4 • hypochlorous acid (HOCI), • hypochlorite (ClO -), and • chlorine (Cl -), which species combined provide a total chlorine concentration, wherein the stabilised hypochlorous solution is obtained by careful stochiometric control of reactants water, calcium or sodium hypochlorite salt and phosphoric acid utilising: i) a source of de-ionised water having an electrical conductivity of no more than 50μScm-1 at 20°C; ii) a greater than 60% pure calcium or sodium hypochlorite salt; and iii) phosphoric acid, to adjust the pH to between 3.0 and 6.5: • the total chlorine concentration is at or below 300ppm; • the hypochlorous, measured by UV spectroscopy at 230nm, is the predominant species; • the hypochlorite, measured by UV spectroscopy at 290nm, is present at significantly lower levels than that of the hypochlorous, such that ratio of hypochlorous acid to hypochlorite is greater than 7.5:1, and • the solution has a pH of between about 7 and 4 and a shelf life of at least 12 months, at 22°C, such that the amount of hypochlorous present remains at above 80% of its starting concentration, and the pH remains above 4 i) a source of de-ionised water having an electrical conductivity of no more than 50μScm-1 at 20°C; ii) a greater than 60% pure calcium or sodium hypochlorite salt; and iii) phosphoric acid, to adjust the pH to between 3.0 and 6.5: • the total chlorine concentration is at or below 300ppm; • the hypochlorous, measured by UV spectroscopy at 230nm, is the predominant species; • the hypochlorite, measured by UV spectroscopy at 290nm, is present at significantly lower levels than that of the hypochlorous, such that ratio of hypochlorous acid to hypochlorite is greater than 7.5:1, and • the solution has a pH of between about 7 and 4 and a shelf life of at least 12 months, at 22°C, such that the amount of hypochlorous present remains at above 80% of its starting concentration, and the pH remains above 4 • the total chlorine concentration is at or below 300ppm; • the hypochlorous, measured by UV spectroscopy at 230nm, is the predominant species; • the hypochlorite, measured by UV spectroscopy at 290nm, is present at significantly lower levels than that of the hypochlorous, such that ratio of hypochlorous acid to hypochlorite is greater than 7.5:1, and • the solution has a pH of between about 7 and 4 and a shelf life of at least 12 months, at 22°C, such that the amount of hypochlorous present remains at above 80% of its starting concentration, and the pH remains above 4