STERIS’ Coverage Plus NPD® One-Step Cleaner Disinfectant a phosphate-free, one-step cleaner/disinfectant formulated for use on hard non-porous surfaces. This product consists of four quaternary ammonium compounds formulated with a compatible detergent system. It is proven effective in the presence of heavy soil (5% bovine serum) and hard water. Coverage Plus NPD disinfectant contains no perfumes or dyes that could interfere with critical research studies or manufacturing processes. Use-dilution is 1:256.