Biological Safety Cabinets Envirco's line of Biohazard Cabinets are NSF International Standard 49 listed and are suitable for use with Biosafety Levels 1, 2 and 3 per CDC/NIH and NCR criteria. Preparation of chemotherapeutic drugs may also be performed in the Biohazard Cabinet per OSHA requirements. These units are CSA tested, and listed for electrical integrity and safety. Initial onsite testing and certification is included in the Continental U.S.