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Help On Your Worst Day

Not many people know about the Interagency Modeling and Atmospheric Assessment Center, but IMAAC provides essential hazard modeling and decision support information for real-world events, and plans training and exercises involving releases of hazardous materials and weapons of mass destruction at no cost to state and local governments. And they can be your “best ally” in managing large-scale chemical, biological, radiological, nuclear or explosive (CBRNE) events or large-scale releases of hazardous materials, said Erik Gaull, NRP, CEM, firefighter/paramedic III for the Cabin John Park Volunteer Fire Department in Maryland.

Gaull presented “Federal Government Casualty Estimation and Decision-support Capabilities for Large-scale CBRNE Incidents” Thursday Oct. 17 at EMS World Expo in New Orleans.

Led by the Federal Emergency Management Agency (FEMA), IMAAC is a partnership among seven federal agencies, Gaull explained:

  • Federal Emergency Management Agency
  • Department of Defense, Defense Threat Reduction Agency
  • Department of Energy
  • Department of Health and Human Services
  • Environmental Protection Agency
  • National Oceanic and Atmospheric Administration/National Weather Service
  • Nuclear Regulatory Commission

IMAAC’s mission is to be a single point for federal government coordination and dissemination of dispersion modeling and hazard prediction products, explained Gaull. These products represent the federal position during actual or potential incidents involving hazmat or CBRNE, and the information can provide first responders and incident commanders with predictions of hazards associated with atmospheric releases to aid in decision-making to protect the public and the environment.

“We can model virtually anything that’s out there,” said Gaull, and provide critical information including evacuate vs. shelter in place decisions, decontamination information, and incident management techniques. “We can help you on all of these fronts.”

This expert help is available 24-7 at no cost. The contact number for the IMAAC technical operations hub is 877-240-1187.

How do you know when to call? Examples of large-scale events include a large structure fire involving chemicals or hazmat; a tanker truck crash or train derailment with a large hazmat airborne cloud (such as chlorine or large crude oil fire); a major radiological incident such as a nuclear power plant explosion or nuclear weapon detonation; or any hazmat or CBRNE incident when local response assets are overwhelmed. Routine building fires and incidents without hazmat involvement are generally not supported.

Complex chemistry, weather involvement, or serious health-threatening incidents potentially affecting large numbers of people are other reasons to call.

“Any scene where you roll up and go, ‘oh crap,’” said Gaull.

IMAAC strives to deliver informative reports to requestors within 30 minutes of activation, in whatever format is requested (PDF files, GIS-portable formats, Word documents etc.). These reports can characterize the incident, predict the likely plume course, anticipate effects to health and the environment, and coordinate and marshal federal resources. IMAAC products are made available on the Homeland Security Information Network (HSIN) IMAAC page, but they can be delivered during real-world incidents using any method available to the recipient.

Have as much specific detailed information as possible, advised Gaull: the location of the event (street address, GPS coordinates, common place name etc.), product class if known, container information, environment and surroundings, a contact person, and other information that can be helpful. “The more details the better,” he said.

IMAAC also provides atmospheric modeling support for national and local exercises. For training information (provided at no cost) e-mail

IMAAC is developing additional capabilities such as natural gas modeling, tighter integration with local weather field offices, and support for “4th generation” nerve agents. When in doubt, call the IMAAC emergency number.

“Call us as soon as you think you need us,” Gaull said.

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