Microorganisms present a range of resistances to chemical and enzymatic disinfectants and no single disinfectant is effective in all situations. The aim of the present study is to evaluate the bacteriophage as bio-disinfectant in different conditions. Phage was subjected to a standard battery of tests including the In-Use Dilution Method for Testing Disinfectants and the Germicidal Spray Products Test. Results indicate that aerosolized phage can eradicate or significantly reduce the Staphylococcus aureus load on a variety of materials found in the laboratory and hospital-related equipment. Additionally, Bacteriophage was shown to retain full activity under conditions that mimic a hospital environment, i.e., in the presence of non-ionic detergents, hard water, or organic materials. We propose phage as the first biological, narrow-spectrum disinfectant against Staphylococcus aureus, which may augment or supplement the use of broad-spectrum disinfectants.