What Is Preemption?

Traffic Signal Preemption is the process of allowing emergency vehicles to manipulate traffic signals in their path, halting conflicting traffic and allowing the emergency vehicle the right-of-way. This has been proven effective in reducing response times, while simultaneously enhancing traffic safety (by dramatically reducing collisions with innocent motorists who may enter the intersection on a green light, but do not hear or see the approaching emergency vehicle).1


Statistics show that nearly half (40%) of firefighters killed in the line of duty die in traffic accidents enroute to the scene. In 2000, over 500 deaths occurred in accidents involving emergency vehicles2. During the period January 2002 through October 13, 2005, auto liability claims alone cost the Phoenix Arizona Fire Department $3.98 million, while damage to apparatus was estimated at over $730,000. In the 1.8 million miles logged by the Phoenix F.D. during that time period, 507 vehicle accidents occurred, of which 308 were determined to have been preventable3.

Emergency vehicles (fire trucks, police cars and ambulances) pass rapidly through traffic intersections, using sirens and flashing lights to alert other drivers of their passage. Confusion, inattention, mobile phones, car radios, hearing impairment, distracting children, air conditioning, vehicle sound proofing, and failure to see flashing lights cause many serious accidents. First responders arrive at the scene faster with emergency vehicle preemption. Shorter response times for emergency vehicles enable them to arrive at a scene in the initial moments when their key decisions are important. For a fire fighter, arriving a minute sooner may mean being able to stop the spread of a fire. In a medical emergency, saved time may be the difference between life and death, giving medics the opportunity to stabilize and treat a victim3.


The result is 8,000 injuries, approximately 500 fatalities, and even further damage to city personnel, civilians, and equipment. Millions of dollars are lost to liability claims and vehicle repairs. Emergency vehicle accidents are a worldwide problem with numerous injuries, fatalities and huge costs resulting from lawsuits. Consider the costs to city budgets of one traffic accident involving an emergency vehicle. The scene of the emergency loses its critically needed assistance, and a second crisis is created. Additional local or nearby emergency vehicles must be dispatched to both scenes, straining limited resources and increasing the chances for yet another incident.


  1. The area that emergency vehicles can cover within required response times
  2. Safety of emergency vehicle personnel and the public
  3. The speed of responders in reaching a scene
  4. The time available for making critical decisions


  1. Response times
  2. The cost of replacing emergency vehicles damaged in crashes
  3. The damage to public and private property caused by delayed responses to fires, chemical spills, and other hazardous events
  4. Fatalities
  5. The legal liability of public agencies when motorists are injured
  6. Insurance premiums due to an improvement in ISO classification

1 Source: Intelligent Transportation Systems, U.S. Department of Transportation article “Enhancing Public Safety, Saving Lives: Emergency Vehicle Preemption”(FHWA-JPO-99-002)

2 Source: National Highway Traffic Safety Administration

3 Source: Judi Villa, Arizona Republic front-page article “Fire Truck Wrecks Costly for Phoenix”(12/20/2005)

Meet the Firefighter/Engineer that designed our Preemption System.

However, being a firefighter is only half the story, Adam has spent over a decade designing systems for defense contractors that use Radio and GPS. He knew from his diverse experience that existing GPS, Optical and cellular Traffic Signal Preemption System weren't meeting the two most important needs, affordability and performance.

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GPS Preemption Compatible with Optical

Do you already have an Optical Preemption System or Infrared Preemption system or commonly referenced by a brand name such as Opticom ®, Emtrac ®, Tomar ®, Strobecom ® or MIRT ®? Upgrading to a GPS Traffic Signal Preemption System is affordable and simple.

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FireRescue1 Industry Article

Could traffic preemption reduce fire response times and save lives? Once overlooked as expensive and impractical, signal preemption has come a long way since the 1970s

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Fire Departments

As the call comes in and your department is focused on digesting and learning the circumstances of the emergency and the scene while enroute, traffic should not be a major consideration. Today�s electronically distracted drivers have made the opposite even more true. Motorists already respond to the presence of an emergency vehicle differently but often distracted drivers do not react at all.

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Police Departments

The Eliminator Emergency Vehicle Preemption (EVP) System provides specific features designed for Police Departments. Most EVP systems use ETA or GEO windows to define when or where preemptions occur. However Police Cars typically travel at a higher rate of speed than Fire and EMS, specifically faster than the larger vehicles such as Engines, Tankers, and Ladder Trucks.

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From the moment an emergency run begins, there is potential for an even greater disaster; colliding with another vehicle enroute to the scene of the emergency. This often results in that vehicle and its occupant(s) becoming an additional emergency incident to address. Many cities have experienced an increase in collisions with emergency vehicles at intersections, but emergency vehicle preemption has been shown to effectively reduce the probability of these collisions by giving ambulances the right of way.

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