Shelter-In-Place: Indoor Exposure Assessment During an Airborne Chemical, Biological, Radiological, and Nuclear (CBRN) Event

The goal of Shelter-In-Place (SIP) is to reduce human exposure to chemical, biological, radiological, and nuclear (CBRN) agents in the event of an accidental or intentional airborne release into the outdoor environment. The Air Force Bioenvironmental Engineering (BE) career field is responsible for providing hazard identification, evaluation, and control capabilities as well as executing health risk assessments to recommend appropriate courses of action to commanders pre-, trans-, and post-incident. Specifically, BE is responsible for providing sampling, identification, and quantification input to hazard prediction models and supporting evacuation plan development to provide risk-based control recommendations. This also includes providing exposure and contamination control recommendations for sheltered populations. A Gaussian plume model combined with indoor box model was used to test the consequences associated with the delay of implementing SIP procedures. It is imperative that emergency planners pre-plan the installation SIP protocol for likely scenarios identified during the various vulnerability surveys conducted for both on- and off-installation. The decision to shelter-in-place must be made immediately in order to reduce the exposure and depending on scenario, a delay greater than one minute can significantly increase the exposure resulting in additional casualties presenting at the local medical treatment facility