The six branches of the star are symbols of the six main tasks executed by rescuers all through the emergency chain:[4]

  1. Detection The first rescuers on the scene, usually untrained civilians or those involved in the incident, observe the scene, understand the problem, identify the dangers to themselves and the others, and take appropriate measures to ensure their safety on the scene (environmental, electricity, chemicals, radiations, etc.).
  2. Reporting The call for professional help is made and dispatch is connected with the victims, providing emergency medical dispatch.
  3. Response The first rescuers provide first aid and immediate care to the extent of their capabilities.
  4. On scene care The EMS personnel arrive and provide immediate care to the extent of their capabilities on-scene.
  5. Care in Transit The EMS personnel proceed to transfer the patient to a hospital via an ambulance or helicopter for specialized care. They provide medical care during the transportation.
  6. Transfer to Definitive care Appropriate specialized care is provided at the hospital.

Designed by Leo R. Schwartz, Chief of the EMS Branch, National Highway Traffic Safety Administration, the six-barred "Star of Life" was adapted from the Medical Identification Symbol of the American Medical Association and was registered as a certification mark on February 1, 1977.

Each of the bars of the blue "Star of Life" represents the six system function of the EMS System.

The snake and staff in the center of the symbol portray the staff Asclepius who, according to Greek Mythology, was the son of Apollo, god of light, truth and prophecy.  Supposedly, Asclepius learned the art of healing from the centaur Cheron;  but Zeus, king of the gods, was fearful that because of Asclepius' knowledge, all men might be rendered immortal.  Rather than have this occur, Zeus slew Asclepius with a thunderbolt.  Later, Asclepius was worshipped as a god and people slept in his temples, as it was rumored that he effected cures of prescribed remedies to the sick during their dreams.

Asclepius was usually shown in a standing position, dressed in a long cloak, holding a staff with a serpent coiled around it.  The staff has since come to represent medicine's only symbol.