A GPS System For Fire Department & EMS Dispatch

Modern dispatching of firefighting and emergency medical services has become more than a simple reaction to an urgent problem. It is also the strategic husbanding of often scarce resources, in a time when budgets are tight and competitive pressures are intense.

"We have very stringent response times (mandated) under a performance bond. We must place a paramedic ambulance at the scene of an emergency in no more than eight minutes from the time that the call is received. Failure impacts lives as well as dollars," said Patrick Smith, president and CEO of the Regional Emergency Medical Services Authority (REMSA). This non-profit group is headquartered in Reno, NV, and provides paramedic ambulance service in a 17-county area, covering 6,000 square miles, with just 14 ground and one helicopter ambulance. The management tool it uses is VisiCAD, a real-time interactive computer mapping and data system designed specifically for the purpose by American TriTech, based in San Diego.

REMSA is one of more than 40 public and private ambulance services around the world which have adopted the system. Other users include the Denver Fire Department, the St. John Ambulance Service (New Zealand's largest, in Auckland) and the Staffordshire Ambulance Service NHS Trust, which covers 1,000 square miles and a population of 1.5 million people around Stafford in the United Kingdom.

For Smith and his colleagues at REMSA, the VisiCAD system provides not just an address where a medical emergency is occurring, but also a computer-displayed map, the status of near-by units and their relative locations. The locations are constantly updated by a Global Positioning System (GPS) receiver in each ambulance that is linked to the central dispatch center by an 800 Mhz digital wireless radio system.

That same system also feeds data to the ambulance crews, which allows the most efficient use of resources. Each ambulance has access to a database which contains the Dr. Clawsen's Emergency Medical Dispatch Protocols and other data. A scanner allows the incorporation of additional grabbed visual information, such as the layout of a mobile home park or of a public park or the floor plan for a hospital, hotel, casino or other large public building with multiple entrances and levels.

These images and other site-relevant data become intelligent attributes which pop up when the location is entered into the system. The computer map, derived from Bureau of the Census TIGER databases that have been visually enhanced, is scalable.

Included in the database is intersection and routing information, which is dynamic, based upon previous experience and including environmental factors such as weather and the time of day and the day of the week. This constantly updated history allows REMSA to assign and position its crews efficiently.

Into Action

"We know that we are going to need all units in position during a weekday rush hour," Smith said, "But at 5 A.M. on a Sunday, for instance, we may need only three crews and ambulances to meet the demand. Anytime an ambulance is dispatched, the system adjusts the other units to new positions so that they can respond in the most timely manner. The American TriTech system is the heart of our dispatch system. It provides maximum efficiency because it will scale to any user-defined box. The dispatcher can tell that ambulance crew exactly where to turn, and can monitor their location from the GPS as they respond. We use a dual screen system, with the map on one monitor and the location data on the other with line-by-line directions."

REMSA has one of the smaller VisiCAD EMS systems deployed. A more typical user is the Acadian Ambulance Service of Lafayette, LA, which covers 26 of the state's 64 parishes with 140 ground ambulances, four helicopters and two fixed-wing air ambulances. Acadian uses a VHF radio dispatch system to communicate with its crews and feed back GPS data to the dispatch center. The ground ambulances also receive data from the central dispatch through mobile data terminals. Acadian uses an integrated paging system with automatic reminders to alert crews when they have been at the site of an emergency too long.

"Sometimes," said John Zuschlag, the ambulance service's senior vice president of information and communication systems, "a crew can get caught up in the moment and lose track of the time. Lives often depend upon getting someone to the hospital as quickly as possible. The system allows us to better manage the triage in a (mass casualty) emergency. Another system also alerts the crew when they have been at a hospital too long and need to get themselves back out in the field to meet other emergencies."

Like REMSA, Acadian uses a scanner to add floor plans and other visual data to the mapping system. That includes a series of 35-mm high- resolution color photographs of night landing sites for its helicopters. Intelligent icons are used to help dispatchers immediately identify hospitals, schools, apartment complexes, mobile home parks and airports. A mouse click on the icon brings up scanned-in schematics and floor plans of these locations, along with other relevant data.

Acadian has been using the system since 1994, and plans to install a new version of the software with even more functionality in 1997. The operating system is the graphics-friendly Windows NT, rather than UNIX, and it is usually mounted on a personal computer with a dual monitor card. (Actually, a system can display on up to nine monitors at once but to date no one has used more than three.)

New Combination Of Ingredients

American TriTech co-founder and director of business development, Christopher Maloney, explained that he and his partners designed the system specifically for emergency medical services. GPS allows users to optimize their operations for quicker response time and more efficiency they know where every unit is at any given time.

When a "request for service" is received by a dispatcher, a link to the telephone system automatically reads the location of the caller and displays that on the monitor. A triage question system also displays to allow the call taker to determine the nature and extent of the emergency for instance, if someone is in need of instructions for CPR or how to assist with a birth. Even as the call taker is guiding the caller through the triage questions, the data is being fed to the dispatcher.

The dispatcher determines the closest unit available to take the call and can ask the system for recommendations.

And note: the system includes an AI component that calculates the best route from the responding unit to the site of the emergency, considering travel time and previous history with calls from that location, while also factoring in weather and traffic conditions based upon previous experiences at that time of day and day of the week. Once the dispatcher commits resources to a call, the system will send all of the relevant data to the crew as the ambulance rolls to the scene.

The average file size for a city or large area map is about 100 megabytes. When the maps are separated into different zones, then the total size of the files may be as much as 300 megabytes: more as scanned-in data for intelligent data point attributes is added.

American TriTech buys the enhanced TIGER data from Business Location Research (BLR) of Tucson, AZ, which primarily provides site- selection data to such customers as telephone companies and fast-food restaurant chains. BLR has two teams of 40 people each, who constantly update the enhanced data. Each team member is responsible for five municipal areas and there are 42 data layers that display such features as street, road, railway and highway boundaries, parks and golf courses, and even political and administrative boundaries such as ZIP codes.

Some of this data is acquired from legacy material such as city maps, some from satellite photography with a three-meter resolution, and a very small amount from ortho-rectified satellite images with a one-meter resolution. All of these varying graphics and imaging sources demand an operating system that is both powerful and flexible.

Maloney said Windows NT was picked as the operating system because it allowed quicker development time and expandability, because the hardware is readily available and less expensive than workstation alternatives and because many people are already familiar with and therefore easy to train on a Windows-based system.

American TriTech already provides around-the-clock service support for its customers, as well as a three-day annual refresher course at the customer's location. It is looking for ways to expand the functionality of the system.

Expansion Ahead

In the future, photographs and three-dimensional representations of complex and crowded urban terrain such as high-rise-laden downtown areas may be incorporated. Ambulance crews may have access to these images with monitors rather than just character-based data terminals. It may even be possible to support virtual reality "fly-through" visualizations of routes to the emergency location. The company continues to develop new features including better decision-support software. It is also interested in operations research applications.

Already, Maloney said, the TIGER data files are being overlaid and enhanced with satellite images. Thus far, "the reason we're doing that is not because it's particularly useful but because it's sexy," he admitted. "It does help put a location in a larger geographical context but the people using the system usually know where they are without that. It is a way to sell the system to non-experts such as government officials."

American TriTech deployed the first VisiCAD fire dispatch system in Denver in December 1996. This is a beta-test site run by the Denver Fire Department.

Juan Guttierrez, the department's chief of fire communications, said the system is not using a GPS component but relying on dispatcher monitoring of vehicle locations. It is being tested on more than 40 pieces of fire apparatus (the department has no ambulances), and has been able to enhance the basic mapping data with such features as layers that show the locations of fire hydrants and the flow rate (in gallons per minute) of the water mains that support them. More importantly, the system also indicates whether a hydrant is in or out of service.

"The capabilities are phenomenal," Guttierrez said. "We're just trying to learn the basic capabilities we've been given so far."

Those capabilities include giving the dispatcher information about the equipment and personnel on each truck. The truck closest to an emergency is not always the best one to respond.

"If you need a piece of special equipment like a 50-ton jack or (a hydraulic rescue tool) or special people like those who are trained to handle hazardous materials, then you want to (target) that response with the unit most appropriate to the job," Guttierrez said.

The intelligent attributes feature can also warn a crew of unusual conditions at a site such as hazardous materials, or that a building is an abandoned one with large holes in the floors. That knowledge can save someone's life.

Francis Hamit is a member of the American Society for Industrial Security, National Military Intelligence Association and Association of Former Intelligence Officers. He is a consultant on fire life safety and security issues.