15. Detailed Biosafety Level 2 Requirements (BL2)

BL2 practices to prevent exposure to pathogens transmitted by:

1. Accidental inoculation - needle stick or cut from contaminated sharp object.
2. Ingestion
3. Skin or mucous membrane exposure to infectious material.

In addition to standard microbiological practices listed in BL1, the following additional practices are required at BL2:

Access

• The universal biohazard sign is posted on the door of a BL2 laboratory.
• Entry is limited to those informed of the potential hazard: use the phone numbers on the door sign for more information about the laboratory access requirements.
• Keep animals not involved in the BL2 experiment out of the lab.

Personal Protection

Gloves should be worn in every situation in which there is reasonably anticipated skin contact with the infectious materials. REMOVE gloves when leaving laboratory areas.

• Gloves should NOT be washed or disinfected for reuse.
• Disinfecting agents may cause deterioration.
• Use general purpose utility gloves (rubber household gloves) for decontamination of work surfaces and clean-up of spills. Utility gloves may be decontaminated and reused unless they are peeling, cracked, discolored, or they have punctures, tears, or other evidence of deterioration.
• If gloves become contaminated, REMOVE, WASH HANDS, and replace the gloves.
• Double-gloving may be required for biohazardous procedures.
• Safety glasses and masks should be used when there is a possibility of mucous membrane exposure.
• Lab coats, gowns, or uniforms are mandatory to prevent contamination of street clothing. This protective clothing is to be removed and left in the lab before leaving for non-laboratory areas.

Work Practices

• Do not bend, break or recap needles. Dispose of uncapped needles in needle boxes located as close as possible to the point of use.
• Review the use of sharp instruments in the experiment to minimize the potential for injury.
• Use biological safety cabinets for procedures with high potential for creating infectious aerosols. Procedures may include:
  • centrifuging, grinding, blending, vigorous shaking or mixing, sonic disruption
  • opening containers of infectious materials whose internal pressures may be different from ambient pressures
  • inoculating animals intranasally, and harvesting infected tissues from animals or eggs
• Microbiological work should be done in a biosafety cabinet whenever high concentrations or large volumes of infectious agents are used. Such materials may be centrifuged in the open laboratory if sealed heads or centrifuge safety cups are used and if they are opened only in a biological safety cabinet.

Storage

Post the universal biohazard symbol on equipment where the BL2 experimental materials or human blood, body fluids, or unfixed tissues are handled or stored.

Examples of BL2 work include:

• Work with infectious agents such as S. aureus, Epstein-Barr virus, Vaccinia, etc.
• Work with human blood, potentially bloody body fluids, unfixed tissues. Universal Precautions requires the use of BL2 practices with materials of human origin.

For more details, refer to http://bmbl.od.nih.gov/sect3bsl2.htm.