How NEMSIS Works

The NEMSIS System

The National Emergency Medical Services Information System (NEMSIS) is the national database that is used to store EMS data from states and territories. NEMSIS is a universal standard for how patient care information resulting from an emergency 911 call for assistance is collected.  In short, NEMSIS is a collaborative system to improve patient care through the standardization, aggregation, and utilization of point of care EMS data at a local, state and national level. NEMSIS is a product of NHTSA’s Office of EMS and in collaboration with the University of Utah is the host of the Technical Assistance Center (TAC).

NEMSIS Inner Workings

NEMSIS uses a common computer language known as Extensible Markup Language (XML) to move data.

States and software companies create products that are used to send and receive EMS data in the proper XML format from agencies to states, then on to the National EMS Database.

  1. Local Agencies select elements according to their needs—keeping the national elements AND state elements as part of their selected elements.
  2. States select elements from the NEMSIS Dataset according to their needs—keeping the national elements as part of their selection.
  3. The national elements are transmitted to the NEMSIS TAC to populate the National EMS Dataset.


The following animation is a conceptual representation of how NEMSIS works.