Exposure Control Plan to Prevent Infections with Blood-borne Pathogens

Risks of infection from a single exposure

The rate of seroconversion after a contaminated needle stick is:

< 0.4% HIV positive needle stick
~ 30% HBV positive needle stick
~ 3% HBC positive needle stick

Exposures to blood-borne pathogens in the laboratory may involve:

  • Needle stick or cut from a sharp object known to have been in contact with blood or body fluids.
  • Exposure of mucous membranes with blood or body fluids.
  • Contact of non-intact skin (chapped, abraded, or afflicted with dermatitis) with blood or body fluids.
  • Contact of intact skin or mucous membranes with high-titer HIV materials (cell cultures or culture supernatants from laboratories working with HIV).

If a workplace exposure occurs

  • Eye splash: Use the eye wash for 15 minutes, holding the eye open.
  • Hands or other exposed skin: Wash with antiseptic or soap.
  • Report immediately for antiviral prophylaxis

Prevention - Universal Precautions

Use universal precautions (BL2 work practices) with ALL materials of human origin, without regard to any information about the sample which may be available: the source, serological results, or even information such as heat inactivation. A safe and effective vaccine against Hepatitis B is available and strongly recommended. In addition:

  • Prevent needle sticks by NOT recapping needles.
  • Prevent mucous membrane exposures by wearing your safety glasses and a mask or a face shield.
  • Keep contaminated gloves away from the face.

Spill Clean Up: Clean up blood or body fluid spills according to the following procedure:

  • Contain spill promptly by placing absorbent paper towels over the spill.
  • Wear utility gloves, discard contaminated towels in biohazard bag, and wash the contaminated area with detergent.
  • Flood the area with freshly prepared 0.5% sodium hypochlorite solution for 10 minutes contact time. Clean and rinse the area.
  • Protection of vacuum system from contamination
  • Be sure that collection tubes extend at least 2 inches below the aspirator outlet.
  • Try to locate the collection flask in the biosafety cabinet so that the liquid level can be seen easily and the flask emptied before it overflows. The second (overflow) flask may be located outside the cabinet.
  • Never use a glass flask at floor level unless it is shielded by a plastic container.
  • In BL2 laboratories, plastic suction flasks are preferred.
  • Add disinfectant to the flasks so that the final concentration will be effective (i.e. 1/10 flask volume of sodium hypochlorite. If sodium hypochlorite is used, replace disinfectant daily).
  • A hydrophobic filter should prevent fluid and aerosol contamination of central vacuum systems or aspiration/suction systems. The filter will also prevent hazardous microorganisms from being exhausted by a vacuum pump into the environment.