BioSafety Classification:

Each laboratory falls in a Biosafety Level (BSL) 1-4. As the degree of protection and risk for personnel and the environment of the lab increases, the levels of BSL are designated in ascending order.   Currently, our campus is composed of mainly BSL-1 laboratories. The BSL chart shows how a particular laboratory will be rated depending on the nature of the laboratory. 

Table 1.  Summary of recommended BioSafety levels for infectious agents.

Biosafety Level  Agents Practices

Safety Equpment (Primary Barriers)

Facilities (Secondary Barriers)
1 Not known to cause disease in healthy adults.
Standard Microbiological Practices None required Open bench top sink required
2 Associated with human disease, hazard = auto‑ inoculation, ingestion, mucous membrane exposure

BSL‑1 practice plus:

  • Limited access
  • Biohazard warning signs
  • "Sharps" precautions
  • Biosafety manual defining any needed waste decontamination or medical surveillance policies

Primary barriers = Class I or 11 BSCs or other physical containment devices used for all manipulations of agents that cause infectious materials PPEs: laboratory coats; gloves; face protection as needed

BSL‑1 plus: Autoclave available

3

Indigenous or exotic agents with potential for aerosol transmission; disease may have serious or lethal consequences

BSL‑2 practice plus:

  • Controlled access
  • Decontamination of all waste
  • Decontamination of lab clothing before laundering
  • Baseline serum

Primary barriers = Class I or II BSCs or other physical containment devices used for all manipulations of agents; PPEs: protective lab clothing; gloves respiratory protection as needed

BSL‑2 plus:

  • Physical separation from access corridors
  • Self‑closing, double door access
  • Exhausted air not recirculated
  • Negative airflow into laboratory
4

Dangerous/exotic agents which pose high risk of life threatening disease, aerosol‑ transmitted lab injections; or related agents with unknown risk of transmission

BSL‑3 practices plus:

  • Clothing change before entering on exit from facility

Primary barriers = All procedures conducted in Class III BSCs or Class I or II BSCs in combination with full-body, air-supplied, positive pressure personnel suit

BSL‑3 plus:

  • Separate building or isolated zone
  • Dedicated supply/exhaust, vacuum, and decon systems