Table 4. Animal facility containment levels: summary of practices and safety equipment RISK GROUP CONTAINMENT LEVEL LABORATORY PRACTICES AND SAFETY EQUIPMENT ABSL-1 Limited access, protective clothing and gloves ABSL-2 ABSL-1 practices plus: hazard warning signs. Class or ll BSCs for activities that produce aerosols Decontamination of waste and cages before washing ABSL-3 ABSL-2 practices plus: controlled access BSCs and special protective clothing for all activities ABSL-4 ABSL-3 plus: strictly limited access. Clothing change before entering. Class Ill BSCs or positive pressure suits. Shower on exit, Decontamination of all wastes before removal from facility ABSL, animal facility Biosafety Level; BSCs, biological safety cabinets