This regulation establishes exemptions from the requirement of a tolerance for residues of magnesium sulfate anhydrous (CAS Reg. No. 7487-88-9); magnesium sulfate monohydrate (CAS Reg. No. 14168-73-1); magnesium sulfate trihydrate (CAS Reg. No. 15320-30-6); magnesium sulfate tetrahydrate (CAS Reg. No. 24378-31-2); magnesium sulfate pentahydrate (CAS Reg. No. 15553-21-6); magnesium sulfate hexahydrate (CAS Reg. No. 17830-18-1); and magnesium sulfate heptahydrate (CAS Reg. No. 10034-99-8), collectively referred to as magnesium sulfate, when used as an inert ingredient in antimicrobial pesticide formulations applied to food-contact surfaces in public eating places, dairy- processing equipment, and food-processing equipment and utensils at an end-use concentration not to exceed 4400 parts per million (ppm). Ecolab, Inc. submitted a petition to EPA under the Federal Food, Drug, and Cosmetic Act (FFDCA), requesting establishment of exemptions from the requirement of a tolerance for magnesium sulfate. This regulation eliminates the need to establish a maximum permissible level for residues of magnesium sulfate when used in accordance with these exemptions.