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  3. Disasters


Disaster can strike at any time and in any place, building slowly, or occurring suddenly without warning.

Whatever the scenario, as the federal government's emergency management and preparedness agency, FEMA serves in a coordination and integration role, collaborating with the agency's local, state, federal, tribal, private sector and non-profit partners before, during and after disasters to ensure that all survivors are included and their needs are met.

Since 9/11, DHS has made significant progress in how we respond to a wide range of threats, from natural disasters to coordinated attacks.

FEMA has established sixteen Incident Management Assistance Teams (IMATs) that utilize the ICS Incident Command System as their core organizational management structure.

Using the authorities outlined under the Homeland Security Presidential Directive -5 and the Stafford Act, FEMA leads the federal interagency team in support of state governors.

Airplane and Ambulance on a Tarmac

It is important for public safety agencies (such as law enforcement, emergency medical services, and fire services) to be able to provide and maintain communications before, during, and after a disaster or emergency.

Disasters may require resources beyond what local and state authorities can manage. We provide disaster emergency communications through six geographically dispersed Mobile Emergency Response Support (MERS) detachments and a pre-positioned fleet of Mobile Communications Office Vehicles.

The primary DEC missions are to:

  • Enable interoperable communications to ensure coordination and collaboration among Federal, State, Tribal, Territorial, and local governments, as well as the private sector and non-governmental organizations;
  • Enable effective and efficient Federal disaster response and recovery by providing Operational Communications support (voice, video, and data) to first responders in coordination with other mission partners, stakeholders, and survivors;
  • Support all-hazard emergency management across the entire disaster management lifecycle - preparedness, mitigation, response, and recovery

Goals & Objectives:

  • Deploy, install, operate, maintain, and protect telecommunications and operations assets in response to all-hazards disasters and in support of planned special events.
  • Ensure continuity of disaster emergency communications through FEMA regional fixed facilities positioned throughout the Nation.
  • Support the disaster emergency communications needs of state and local governments.
  • Establish JFOs and provide for their continuing operational communications and systems needs.
  • Aid in evaluating post-disaster communications needs in support of the restoration of the communications infrastructure.

Mobile Emergency Response Support

Mobile Emergency Response Support provides self-sustaining telecommunications, logistics, and operations support through detachments (staff, equipment, and equipment assets) that are immediately deployable. These detachments can be transported nationally and are able to work together to support a large disaster field office and multiple field operating sites within the disaster area. MERS detachments are centrally managed and strategically located across the United States to rapidly respond to incidents at any time, and in any environment.  MERS detachments are also called upon to support National Special Security Events as well as other planned special events and activities.

Photo of the ten FEMA Regions

Each detachment has the following capabilities:


  • Provides an office and communications platform capable of moving into a disaster on short notice and can be staffed to meet situational needs.
  • Ensures systems interoperability through deployment of:
    • Radio equipment (such as Ultra High Frequency, Very High Frequency, and 700 MHz tactical radios)
    • Satellite backhaul (to provide voice, data, and video support via satellite)
    • Line of Sight / Near Line of Sight microwave systems (for moving data in and out of a disaster area)
    • Cross-banding

The GreenHornet: Large-scale emergency operations vehicle


  • Has generators to supply the power generation requirements of one or more facilities or locations within the disaster area.
  • Can provide the heating, ventilation, and cooling requirements for a large office building.
  • Can provide diesel fuel.
  • Can provide potable water.


Fuel Tanker


  • Support personnel with planning; alert, notification, and deployment monitoring; situational awareness; and reporting.

Incident Response Vehicle


Mobile Communications Office Vehicles

Mobile Communications Office Vehicles are multi-purpose central office facilities that are activated to support FEMA’s response and recovery to/from a disaster. These vehicles are fitted with work stations and satellite communications to provide voice and data connectivity to the FEMA network to support survivors.

Mobile Communications Office Vehicle

During initial deployment, Mobile Communications Office Vehicles are guided by operational coordination, control, and communications requirements received from on-scene emergency management personnel. They’re able to quickly establish a center for survivors to apply for assistance, which is known as a mobile disaster recovery center.

State and Local Radiological Emergency Preparedness

DHS’s Domestic Nuclear Detection Office has trained more than 23,000 state and local officers and first responders in radiological and nuclear detection. In addition, through the Securing the Cities initiative, nearly 13,000 personnel in the New York City region have been trained in preventive radiological and nuclear detection operations and nearly 8,500 pieces of radiological detection equipment have been deployed.  The Administration has proposed expanding the Securing the Cities initiative to additional high risk regions of the country.


BioWatch is a federally-managed, locally-operated, nationwide bio-surveillance system designed to detect the intentional release of aerosolized biological agents.  Through the BioWatch program, an environmental surveillance system that provides early detection of biological agents, DHS’s Office of Health Affairs has collected over 1.1 million samples in more than 30 cities nationwide over the past five years to enhance protection and preparedness for high-consequence biological threats.

Ready Business Campaign

FEMA promotes private sector preparedness through its Ready Business campaign, a nationwide initiative that provides materials to businesses to encourage continuity planning and crisis management.  Ready Business is part of larger preparedness outreach efforts by FEMA that include the Ready campaign and Citizen Corps, to encourage Americans to prepare for emergencies in their homes, businesses, and communities.

Risk Mitigation Training

Each year, more than 33,000 state, local and private sector partners participate in risk mitigation training on a range of topics including managing floodplain development, planning for post-disaster integrated management, conducting benefit cost analysis and emergency management planning, preparedness, training and education.

Since fiscal year 2003, DHS has awarded more than $50 billion in preparedness grant funding based on risk to build and sustain targeted capabilities to prevent, protect against, respond to, and recover from threats or acts of terrorism and natural disasters.

Threat and Hazard Identification and Risk Assessments (THIRAs): Beginning in FY 2012, all states and urban areas receiving homeland security grant funding are required to develop and maintain a Threat and Hazard Identification and Risk Assessment, which includes the range of threats and hazards faced by an applicant. Through the THIRA process, states will compare existing capabilities with target capabilities to identify potential gaps and focus grant funding accordingly.

  • Disaster Assistance

    Disaster assistance is financial or direct assistance to individuals, families and businesses whose property has been damaged or destroyed and whose losses are not covered by insurance.

  • Disaster Response and Recovery

    Every year, disasters put millions of Americans in danger and costs billions of dollars in property damage.

  • Resilience

    DHS works with all levels of government, the private and nonprofit sectors, and individual citizens to make our nation more resilient to acts of terrorism, cyber attacks, pandemics, and catastrophic natural disasters.

  • Surge Capacity Force (SCF)

    If a disaster exceeds the capacity of the FEMA disaster workforce, the Secretary of Homeland Security is authorized to activate the DHS SCF to change the federal response to a catastrophic disaster.

  • Training & Technical Assistance

    Training, technical assistance and exercise resources for citizens and first responders.

Last Updated: 11/01/2022