They create conditions that allow for the maintenance of an aseptic environment for pharmaceutical manufacturing and research, as is critical in many situations. They shield the operator and materials from cross-contamination, and by maintaining the integrity of processing systems, sensitive processes such as drug formulation and cell culture. These boxes also act as a physical prevention from cross contamination, ensure protection of the products and personnel engaged in the manufacturing process. Sterile glove boxes can also have integrated HEPA or ULPA filtration systems to provide an ISO Class 1 barrier to outside influences or to confine hazards within.