Emergency Service Unit

An Emergency Service Unit (ESU) is a multi-faceted and multi-talented element within the special operations commands of some U.S. municipal, county, or state-level law enforcement agencies. ESUs exist mainly in the regional New York City metropolitan area but some exist in a few other jurisdictions outside the region. ESU is also synonymous with the term Emergency Services Squad (ESS) and Emergency Service Detail (ESD). An ESU operates at the direction of the command staff and responds to emergency and high-risk situations that occur outside the scope of duties of responding patrol and criminal investigation units. ESU members train continually both in-house, with other local, state, federal and military specialized units and sometimes members of a Federal Emergency Management Agency (FEMA) Urban Search & Rescue (USAR) Team.

An ESU provides services analogous to the functions of a Special Weapons and Tactics (SWAT) team. ESUs respond to high-risk, tactical operations involving barricaded suspects, hostage situations, high-risk warrant service, tactical crowd control and dignitary/VIP protective operations. ESU's also provide operations and technician level response to hazardous materials (HAZMAT) incidents involving the presence of industrial or illicit chemical, biological or radiological agents involving criminals or terrorists. The ESU responds to rescue victims from structural collapse, high-rise structure, confined spaces, trench collapse, vehicle and rail car accident, and machinery accident entrapmnts.

Many ESUs also perform both surface and under-water victim rescue, searches and evidence recovery as well as to provide "crisis response" to incidents involving psychologically disturbed individuals. ESU members sometimes provide immediate fire suppression and victim rescue for fires occurring in massive and highly populated structural locations that are under the direct jurisdiction of a state or municipal authority. ESU's operations are often supported by a Canine (K-9) response capability and members often respond to incidents involving dangerous animals and reptiles. In some jurisdictions, ESU members may provide medical support and team member rescue during tactical operations and sometimes staff a dedicated ambulance.

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