Biosafety levels or BSL determine the protective measures required in a laboratory setting to protect workers, the environment, and the public against infection. The Centers for Disease Control and Prevention (CDC) sets BSL. Biosafety Level 1 Sign is ideal for marking laboratories that follow Standard Microbiological Practices and require no special equipment or design features. Moving upwards, Biosafety Level 2 signs are suitable for laboratories that have handwashing sinks, eye washing stations in case of accidents, and doors that automatically close and lock. Higher Biosafety Levels (Level 3 and Level 4) include specialized controls for laboratories with a very high and life-threatening risk of infections.