FLUIDSHIELD* Surgical Masks are designed to provide the maximum level of fluid resistance recognized by ASTM F2100-11.ASTM F2100-11: The Standard for Fluid-Resistant issues guidelines for performance of medical face masks including a requirement for fluid resistance and particulate filtration. ASTM F2100-11 standards also call for mask packaging to be clearly labeled with the level of protection in one of three levels: 1 2 or 3. This standard reinforces the importance of labeling to identify protection level based on fluid resistance filtration and breathability. This greatly simplifies the process of mask selection. ASTM F2100-11 is recognized by the FDA as the standard for medical face masks.