How to Properly Use BAC Water in Multi Dose Vials Uses of Bacteriostatic Water for Injections and Where to Get It Bacteriostatic Water (Bac Water) 10ML SSP Research How to Store Bacteriostatic Water Safely Confused about whether BAC water needs refrigeration after opening? According to USP standards and Pfizer's own guidance, both room temp (2025C) and refrigeration are acceptable Your eyes are your first line of defense. Good BAC Water: Crystal clear, odorless (faint alcohol scent), and painless. Bad BAC Water: Cloudy, particulate matter, strong chemical smell, or severe burning.