Clorox Commercial Solutions® Ultra Clorox® Germicidal Bleach is the first and only product to obtain federal and state EPA registration for killing Clostridium difficile (C. diff) spores on hard, nonporous surfaces when used as directed. This high-quality, hospital-use disinfectant kills a broad spectrum of microorganisms on surfaces such as exam tables, countertops, floors and hallway walls as well as food-contact surfaces.*