Early-Phase Emergency-Worker-Protection Stay Time Tables for Responders with a Variety of Health Physics Information and Personal Protective Equipment
P.D. Bailey1; C. Yu2; S. Kamboj2; and J.-J. Cheng2 (1US Department of Homeland Security, Environmental Measurements Laboratory; 2Argonne National Laboratory)
The Operational Guidelines Task Group (OGT) has developed operational guidelines (Group A) to be used by state and local responders in the early phase of responding to a radiological dispersal device incident. The Group A operational guidelines cover access during emergency response. They are presented in a series of reference tables that show maximum stay times relative to potential doses that are based on just one item of health physics information (e.g., radiation detection data, radionuclide identification). (During the early phase of a response, federal assets may not be readily available or may not have arrived yet, and there may be little information on the nature and extent of the radiological release.) The methodology used by the OGT to derive Group A stay times is consistent with the Federal Radiological Monitoring and Assessment Center assessment manual, and it expands the manual's applicability to situations not conceived of when the manual was last updated. Pathways considered include inhalation and direct ingestion of resuspended particles, external dose from submersion in the radioactive cloud, and external exposure from material deposited on the ground. Since different communities have different levels of health physics expertise and access to different personal protective equipment, the stay times are tabulated to account for these differences. The health physics information may include or be limited to measurements of the external exposure rate, gross alpha surface contamination, beta/gamma surface contamination, and/or air concentration. Radionuclide-specific correction factors are also included. In all but the worst cases, the more pertinent the available information is, the longer the stay times can be. The stay times depend strongly on the type of contamination (alpha versus beta-gamma emitters) and the type of respirators used. Thus, the ability to differentiate them is critical for estimating and applying accurate, appropriate stay times.
