A method of preventing microbiofouling on the surfaces of equipment in contact with in an industrial water system which comprises adding to the aqueous system an anti- microbiologically effective amount of a stabilized sodium hypobromite solution, said solution having been prepared by the steps of:
- a. Mixing an aqueous solution of alkali or alkaline earth metal hypochlorite having from about 5 percent to about 70 percent available halogen as chlorine with a water soluble bromide ion source;
- b. Allowing the bromide ion source and the alkali or alkaline earth metal hypochlorite to react to form a 0.5 to 30 percent by weight aqueous solution of unstabilized alkali or alkaline earth metal hypobromite;
- c. Adding to the unstabilized solution of alkali or alkaline earth metal hypobromite an aqueous solution of an alkali metal sulfamate in a quantity to provide a molar ratio of sulfamate to hypobromite of from about 0.5 to about 7;
- and,
- d. Recovering a stabilized aqueous alkali or alkaline earth metal hypobromite solution.