Overview
This lecture introduces biosafety laboratory levels, focusing on secondary containment and key features that distinguish BSL-1 through BSL-4 labs, with emphasis on BSL-3 lab design.
Laboratory Containment Concepts
- Primary containment protects laboratory personnel by containing hazardous sources within the lab.
- Secondary containment prevents infectious agents from escaping the lab and protects people outside.
Biosafety Laboratory Levels
- There are four biosafety levels: BSL-1, BSL-2, BSL-3, and BSL-4, each with increasing containment and safety features.
- BSL-1 and BSL-2 have similar lab designs and safety features.
- BSL-3 labs have high containment with added design features for riskier agents.
- BSL-4 labs provide maximum containment for the most dangerous pathogens.
Lab Design, Equipment, and PPE Differences
- Each biosafety level adds extra lab design features, safety equipment, practices, and personal protective equipment (PPE) compared to the level below.
- BSL-2 labs include enhancements over BSL-1, and BSL-3 labs add more features compared to BSL-2.
Risk Assessment & Lab Selection
- Risk assessments determine the required biosafety level when handling biological agents.
- BSL-2 labs typically handle risk group 2 agents; BSL-3 labs handle risk group 3 agents.
- Large quantities or high concentrations of risk group 2 agents may require a BSL-3 lab.
- Risk group 3 agents can sometimes be worked with in a BSL-2 lab with extra PPE and stricter practices (termed "BSL-2 plus").
Key Terms & Definitions
- Biosafety Level (BSL) — Laboratory classification system defining containment based on risk.
- Primary Containment — Procedures and equipment that protect laboratory workers from exposure.
- Secondary Containment — Lab design features that prevent the escape of agents into the environment.
- Risk Assessment — Evaluation of potential hazards to determine the appropriate biosafety level.
- Personal Protective Equipment (PPE) — Clothing and equipment to protect personnel from biological hazards.
Action Items / Next Steps
- Review the differences in lab design, equipment, and PPE for each biosafety level.
- Prepare examples of primary containment methods for discussion.