BSL |
Agents |
Practices |
Safety Equipment
(Primary Barriers) |
Facilities (Secondary Barriers) |
1 |
Not known to consistently cause disease in
healthy adults |
Standard Microbiological Practices |
None required |
Open bench top sink requireda |
2 |
Associated with human disease, hazard =
percutaneous injury, 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 II BSCs or
other physical containment devices used for all manipulations of agents that cause
splashes or aerosols of 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 BCSs or
other physical containment devices used for all open 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 infections; or related agents with
unknown risk of transmission |
BSL-3 practices plus: Clothing change before entering
Shower on exit
All material decontaminated 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 and exhaust, vacuum, and decon systems
Other requirements outlined in the text |