Post Biological Incident Response Procedures


Biological Laboratory Re-Entry

The Biosafety Professional and/or EHS emergency responder(s) with assistance from the PI or supervisor will make the determination that an area is safe for reentry after a biohazard incident. Others are not to enter or reenter the area without the consent of the Biosafety Professional and/or EHS emergency responder(s) for any reason until the area is released. The Biosafety Professional and/or EHS emergency responder(s), if appropriate, will allow authorized people to re-enter and monitor, control, investigate, remove, rebuild, reinforce, and perform temporary fixes for the facility as necessary before others have access to the area.

Universal precautions shall be used when there is a potential exposure to body fluids or Biohazardous materials. A hazard evaluation of the site by the Biosafety Professional and/or EHS emergency responder(s) can identify areas of potential exposure to laboratory and cleaning personnel. The hazard evaluation will identify the hazardous areas to be decontaminated, followed by cleaning methods to remove the released material.

Criteria for Re-occupancy of Area

The Principal Investigator (PI) or supervisor, upon completion of appropriate decontamination procedures, should have assurance that the decontamination has been effective. The PI or supervisor defines the level of assurance required and the conditions under which a release or spill area can be released for normal occupancy. Personal observation during the application of known effective chemical disinfectants in sufficient concentration and adequate contact times may be the criterion selected to allow research to continue following the release or spill of an agent having little human pathogen potential. Another PI or supervisor may delegate this responsibility to an appointed laboratory safety officer. This approach may be adequate for release or spills of low risk agents in properly isolated areas that allows air dilution and settling of airborne particulate before the decontamination process. A critical criterion affecting decisions to re-occupy facilities following a release or spill is personal knowledge by the PI, supervisor or safety officer that complete implementation of the prescribed disinfecting and decontamination procedure was accomplished. This criterion is usually adequate for releases or spills confined to properly operating Class II and Class III safety cabinets.

As the degree of potential hazard increases, the PI or supervisor may add a refinement, such as swab sample verification for surface contamination of residual viable agents following disinfecting. Alternatively, strategically located cloth or paper patches seeded with resistant microorganisms, such as spores of Bacillus stearothermophilus, are effective indicators of disinfection efficiency. These refinements are not direct reading and will sacrifice some time due to incubation requirements that confirms status of viable indicator microorganisms. Accurate swab sampling for the agent will be achieved only if actual laboratory tests have established the reliability of sampling and assay methodologies, and quantitative relationships between sample recovery vs actual level of contamination. Such methodologies are established and available for spores of indicator microorganisms, but their use during wet chemical disinfection may restrict selection of more effective chemical disinfectants with the more resistant spores. This may not be consistent with other laboratory restrictions on the use of disinfectants having the undesirable properties often associated with sporicidal contaminants. The spore indicators are, however, particularly effective for determining the efficiency of gaseous disinfecting procedures. Using spore indicators, with the “no viable organisms present” criterion, is recommended for determining when laboratory operations may resume following a major release or spill of biohazardous material in the open laboratory.