Definition - What does Bio-Safety Level mean?
Bio-safety level refers to a graduated level of safety precautions used to ensure the safe housing of dangerous biological agents in an enclosed environment, usually a laboratory. The biosafety levels range from 1, which is the lowest, to 4, which is the highest. These levels have been set in the United States by the Centers for Disease Control and Prevention (CDC).
Safeopedia explains Bio-Safety Level
A bio-safety level that is set at level one might require employees to regularly wash their hands and wear protective clothing. At the other extreme, level 4, such precautions as multiple containment rooms, airflow systems, and sealed container s might be in place. There would also be high level security in place to ensure controlled access to the environment.