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Radiological Emergency Preparedness Program - Hostile Action Based Drills

Hostile Action Based (HAB) scenarios are part of the licensing requirement for Commercial Nuclear Power Plants. Offsite Response Organizations (ORO) will demonstrate enhanced security response capabilities based on post-September 11 security initiatives by introducing HAB scenarios into the REP exercise cycle. 


REP Exercise Scenario and Security Incident Preparedness Enhancements

Following the events of September 11, 2001, the Nuclear Regulatory Commission (NRC) reviewed the emergency preparedness basis for commercial Nuclear Power Plants (NPP) to assess whether the program could adequately address hostile action contingencies (e.g., terrorist attacks), given the programmatic basis on accidental releases. The NRC determined that potential radiological exposure to the public during a hostile action based (HAB) incident is no more severe than in other accident sequences considered in the radiological emergency preparedness basis. However, the NRC and FEMA recognized that HAB incidents could present unique challenges to emergency preparedness programs because they differ from the accident-initiated incidents for which licensees and Offsite Response Organizations (ORO) typically plan, train and exercise.

In July 2005, the NRC issued Bulletin 2005-02, “Emergency Preparedness and Response Actions for Security-Based Events” to collect data on program enhancements undertaken by licensees in order to address potential hostile actions. In 2006, the NRC issued Regulatory Issue Summary 2006-121F as an acceptable implementation methodology for the emergency preparedness program enhancements discussed in Bulletin 2005-02. The NRC also recommended pursuing rulemaking for emergency preparedness program enhancements for several security incident-related and non-security incident-related topics. Additionally, the NRC’s comprehensive review identified several other areas for potential emergency preparedness program improvement and areas requiring increased clarity based on technological advances and lessons learned from drills, exercises and actual incidents.

In 2007, FEMA and the NRC established an Exercise Scenario Task Force to identify, coordinate and promulgate appropriate changes to FEMA and NRC regulations, exercise participation and guidance to make REP exercises more realistic and challenging and less predictable. The Task Force identified proposed changes to the REP Program in three areas:

1. Reducing response organizations’ exercise pre-conditioning by increasing the variability of exercise events.

2. Enhancing security response capabilities based on post-September 11 security initiatives by introducing HAB scenarios into the REP exercise cycle.

3. Providing guidance for varying the amount and type of simulated radioactive releases during exercise play.


The purpose of the FEMA REPP HAB Exercise Tool Kit is to provide Offsite Response Organizations (OROs) with several different "tools" which may be used to facilitate reviews of plans and procedures in advance of an HAB REPP exercise.

FEMA REPP HAB Exercise Tool Kit

For additional documents and tools for HAB, login as a guest here.


Last Updated: 
08/01/2016 - 08:34