THE GROWING SYNERGISM BETWEEN TRAFFIC MANAGEMENT AND PUBLIC SAFETY OPERATIONS

Robert B. Franklin, Jr. 
Lockheed Martin Canada, Transportation Systems



INTRODUCTION 

The systems used to manage the transportation network are becoming more effective and more widespread. Concurrently, their ability to serve as an enabling technology for other public service systems is increasing almost geometrically. As real-time traffic condition and road reports are generated faster and in more detail, interconnection of these systems becomes more and more of a mandate.

While the impact of this increased information flow can be felt across any system such as transit, public works and potentially even a school bus fleet, the area that derives the most benefit is Public Safety --  police, fire and emergency medical. This paper addresses the benefits and hurdles of connecting the traffic management and Public Safety systems.


BACKGROUND

Development of these two systems has been conducted in almost a totally independent mode. And much the same can be said about the operational separation of the two functions. The method and assignment of operational responsibility concerning the role of Public Safety in the operation of the transportation infrastructure varies from state to state in the United States and from country to country in Europe. For the most part these two systems, traffic management and Public Safety dispatch, have been developed and operated much like two smokestacks. 

Before the introduction of Intelligent Transportation Systems or Telematics, most Departments of Transportation managed their systems, they did not operate them; they did not have the tools to do so. They were more concerned about pavement status, bridge repairs and widening projects. It certainly was not real-time operation. As the traffic managers acquired the ability to operate their network increased through the deployment of incident detection systems, the traffic management systems began to develop timely information that could be used to materially assist the dispatch of emergency vehicles. Unfortunately this ability has been slow to mature due to the cost of deploying a robust detection capability. But there is another force that has come to bear that will greatly accelerate this interconnection - the cellular phone.  

In the United States alone there are over 100,000 emergency calls made each day over the cellular network. Almost 90% of these are to report a roadway incident. On a down note, fully 50% of these callers had no idea where they were. So these calls have generated a terrific impact on the Public Safety call-taking and dispatch functions. Nonetheless, it has caused Public Safety agencies to be more concerned about getting solid, reliable information about the road network and they are increasingly turning to the traffic managers or to the traffic management function to get this information. 

Thus, there is a growing requirement to increase the effectiveness of the integration of the two systems - we are going to have to build a bunch of ladders out of these stovepipes.


DISCUSSION

In most of today's applications, information generated by a cellular call received by Public Safety is not automatically transmitted to the traffic management function to be used in the incident detection and verification process. And if it is, it is generally by voice circuit and only as an after thought - it is not even a semi-automated function. The information must then be manually entered into the incident management process. This results in significant delays in deploying a response from a transportation perspective. 

Even more critical are those instances involving an accident with injuries, where the first alert is received by the transportation management system. This same time-consuming manual transfer of information from one system to another significantly impacts the "Golden Hour" which is so important in reducing the fatality rate of the severely injured. 

In the not too distant past this manual and verbal transmission of data was the only means available due to the fact that there was no automation on the transportation management system's side of the equation. But since the installation of Advanced Transportation Management Systems is accelerating and because these systems are normally based on a robust computer suite supported by an ever-growing detection and verification subsystem coupled to a solid data base (usually referenced to a GIS map), everything is in place to allow the Public Safety/transportation management interconnect to progress to a full automatic relationship.

Of additional help, the enabling technologies are becoming very available and economically affordable. For example, improvements in Closed Circuit TV (CCTV) technology and the attendant reduction in their cost have jointly allowed the transportation community to visually cover a much larger portion of their network. The more area covered the more information available to be transferred to the Public Safety agencies.

The 800MHz trunked radio systems being deployed to support Public Safety facilitate the actual interconnect with vehicle-to-vehicle, vehicle-to-center and center-to-center communication becomes possible with appropriate formation of talk-groups. There is far less reluctance to allow another agency on "my" network if their participation can be tailored to only those elements of the network needed for operational coordination.

In short, what is being interchanged between the two systems is voice, video and data.
Given the rapid exchange of these interface products, the two sides of the equation can continue to operate as usual but with an enhanced ability to do their function more efficiently.

There is tremendous value that accrues from this interconnect. For Public Safety these appear not only in the ability to respond more rapidly but also in fiscal savings as well. Chronologically, the first person in the Public Safety organization that sees benefit is the call-taker at the Public Safety Answering Point or PSAP. Receiving rapid and accurate corroborating information will allow the call-taker to make the appropriate dispatch decision far more rapidly. Unfortunately, as stated before, 50% of the cellular callers do not know where they are at the time of the call. Therefor, if information gathered by the ATMS detection devices is rapidly processed and sent to the PSAP, it can greatly assist in determining the actual location of the incident. 

Given that many data elements of a call-taker's screen are common to those found on an incident manager's screen in the ATMS, if the institutional barriers have been broached, the appropriate data elements generated by the traffic management system can be automatically transferred to the Public Safety system. Thus the call-taker can be presented with accurate location information far more rapidly than normally available when dealing with the somewhat excited caller who does not know where he is, only saw the incident in passing and thus passes on either incomplete or inaccurate information.  This will allow the call-taker to make a dispatch decision far earlier than currently possible, pass it on to the appropriate dispatcher and thus be available to take information on a new incident more quickly. 

Similarly, information from the PSAP can be used to begin population of the ATMS incident manager's screen. Using the rule of thumb that 4-5 minutes of clearance time is saved for each minute the response time is reduced, and given the increasing density of cellular phones, being able to automatically (and electronically) receive and input data from the Public Safety system will have a marked salubrious effect on the effectiveness of the ATMS. True synergism!

The next step in the Public Safety process, when responding to an incident is to activate the dispatch mechanism. It is in this area where the interconnect affects the entire Public Safety system for it will not only benefit from receiving information about traffic incidents, it also benefits about knowing the status of the routes used to respond to incidents throughout the region. There are varying levels of interconnect between the two systems but even a basic interconnection with the ATMS at the lowest level could facilitate making far more informed decisions as to the proper responding equipment mix. 

Even more value will accrue when the various developers of the Public Safety Computer Aided Dispatch (CAD) systems make provisions within their data base schema to accept real time input in terms of traffic conditions generated by the detection devices resident in the ATMS. In doing so the CAD routing policies will change minute to minute dependent upon an analysis of the traffic conditions at the time. Most CAD systems recommend one of three potential routes -- shortest, fastest or special purpose (i.e. minimum radius turns for hook-and-ladder equipment or weight-limited bridges and overpasses). Currently these recommendations are all based on static data; there is no provision to deal with construction, lane closures, for whatever reason, or other incidents. Given an interconnect with the ATMS database and a capability to adjust accordingly, the CAD will always be able to recommend the best route. 

The benefits are manifold. More of "The Golden Hour" is preserved in medical emergencies. There is an increase in fleet management efficiencies and most important, the average response time for an emergency call throughout the community is reduced regardless of whether or not it is traffic related.  This last benefit comes from being able to get emergency equipment into and out of service more quickly because of effective routing and the ability to dispatch a tailored as opposed to a standard package of equipment sent on each call. This is a very touchy budgetary item;  as the average response time comes down there will be a tendency to stabilize it at a set time. If the community-wide average response time improves such that it is markedly better than the minimum time generally held to be acceptable, there could be pressure to reduce the size of the Public Safety force which could provide a source of friction between the transportation management the Public Safety agencies. Whether or not this is valid concern has not been established with empirical data but it is a caution raised by several members of the Public Safety community that have looked at the interconnection possibilities.

There is one other benefit that accrues to Public Safety that spills over into the ATMS environment as well. The appropriate traffic management agencies will be able to not only provide more responsive on-scene assistance, but will also be able to accomplish the strategic diversion of traffic in consonance with the desires of the on-scene commander. This strategic rerouting of traffic serves the dual purpose of relieving the strain at the incident and keeping the overall flow of the regional traffic moving in the most efficient manner possible thus minimizing the impact of the incident on the overall regional traffic flow. It is intuitively obvious that reducing the back-up at the incident scene will shorten the "clearance" time. 

From an ATMS perspective this interconnect provides a number of advantages as well. The first of these is much faster notification of traffic incidents. Some traffic engineers have stated that the cellular telephone is the best detection device available. From the traffic engineer's perspective they are everywhere, they are free, there is no shutdown for installation, there is no maintenance and they are almost always "there" particularly in an urban environment. 

To date the cellular phone has been very beneficial in reporting accidents. But this has been in a "voice only" mode and with a fairly significant location error factor on many of the calls. This error factor is about to be eliminated as there are several research efforts about to mature that will enable a cellular phone to be located to at least a 125 meter accuracy and potentially to as low as 20 meters. These research projects look promising in developing a capability to determine not only location but also direction of travel and velocity. And all of this can be done if the phone is powered on, not just during periods of time when it is in use. The potential value as a detection and even as a device to develop link speeds is staggering. Of note - this capability is being developed to support Public Safety, not transportation management so it becomes essential for the traffic managers to be able to demonstrate some bilateral value to Public Safety to obtain this data.

The ties to public safety allow the ATMS managers to perform the strategic re-routing of traffic already addressed.  Probably of equal importance, this interconnect provides the basis for coordinated region-wide planning for incident management and congestion mitigation. Many municipalities pre-position response units during the peak travel hours but this is done with empirical data not reflective of the current (and changing) traffic conditions.  Wrecker and ambulance assignments can be adjusted real-time and as the predictive capabilities of the traffic managers becomes more robust, the results of these algorithms can be input into the positioning equation.

The various transportation departments should also see fleet management efficiencies as more accurate and timely information is made available. Requests for and timing of special purpose equipment can be anticipated, thus accruing the benefit of getting it into and out of service quickly. For example, the time of dispatch for a wrecker is almost always inversely related to the severity of the accident. This is due to the increased time allocated to the investigation as the results of the incident become more serious. In a fatal accident it can be anticipated that the vehicles will not be moved pending conduct of the investigation. Rather than dispatch a wrecker and have it sit at the incident scene, it is far better to allow it to continue to respond to "fender-benders" until the need is anticipated at the major incident site.

Above all, making the interconnect more productive should produce the overall result of reduction in emissions as the flow of traffic throughout the region should move more evenly with less impact generated by incidents.

Generally, the interconnect will fall into one of four levels. The first of these being nothing more than the installation of a ring-down or off-hook telephone circuit. 

By making it easier to connect to the other system, it encourages the beginning of an information exchange philosophy. Even in a "voice only" configuration, a Public Safety dispatcher may also communicate with traffic management personnel to advise them of an incident at a particular location. By emphasizing voice communication between Public Safety and traffic management the two groups act as a team to provide their customer, the general public, better response times, more effective use of the infrastructure and most importantly, more bang for their tax dollar   

With the advent of high-speed communication either through hard wire, radio and/or cellular means, moving more information is becoming the norm. In the not so distant past much of the information received in an Emergency Communication Center came from call boxes strategically located throughout a response area. These call boxes were the information collection point for incidents not only in our neighborhoods but on the highway system as well. But these are disappearing due to the growing presence of the cellular telephone and the emergency numbers, either 911 or 999. 

Voice communication is only the beginning of an integrated team approach to traffic management and Public Safety.  The second level of interconnection involves the ability to pass control of CCTV cameras;  this is a two way street as more and more cameras are being installed by Public Safety to enhance the security of the Central Business Districts (CBD) and high population density areas such as shopping centers and airports. While not all of these cameras will be of use to the transportation management system operators, many will and thus can provide some enhancement to the ATMS as it is being deployed throughout the region.

One major concern is who has access to the tools and who controls them during an incident. Public Safety may want to have the ability to zoom in on an accident scene to assist the on-scene incident commander while the traffic manager may want to zoom out and pan the camera in an effort to implement the proper traffic management response. Both requirements are valid and it will take some close cooperation to work the issue. Beyond control issues are the cost of procurement and maintenance. With an integrated management plan focusing on the development of a team approach, these issues can be worked out to the betterment of all.

The third level of interface is achieved by the automatic exchange of data elements from screen to screen. Given that there is commonality of many data elements recorded by the two systems, being able to simultaneously fill in data fields on both systems with a "single keystroke" will produce savings in the time necessary to arrive at the appropriate management decisions for both systems. While the actual layout of a call-taker's screen differs from that of a traffic manager, there are a number of common data elements. It is fairly simple technically to interconnect the two systems such that the beginnings of an incident report can be generated at the traffic management center as the data is being received and input by a call-taker at the Public Safety communication center. The true issue is being able to provide the requisite "firewall" such that Public Safety privacy information is not inadvertently released to the traffic management system.       

The fourth and most comprehensive level is the automatic cross population of the two system's databases. This is obviously the most difficult to achieve technically but it does provide the most benefit to both systems.  

The one fairly thorny technical problem resides in the mapping and addressing translation areas particularly when a GIS application is being used. While Public Safety uses street addresses for location, the transportation community, understandably so, uses some form of latitude/longitude location specification. The modifications required within the databases to move data from one system to another are not difficult; the true problem lies in the spatial errors introduced when transferring location data from one GIS application to another. Currently there is no conversion program that ensures the requisite accuracy. Errors of as much as 300 meters are not uncommon when transferring from one GIS application program to another. While this would not be a major problem in a rural environment, it can cause severe problems in the urban settings. To date the only way this has been overcome is that all participating agencies agree on a common GIS platform. Industry is working the problem and a solution may be right around the corner but as of now, it does take compromise to solve.

There are some other technical issues to be solved. Translation from one computer operating system to another and cross population of different data base schema can be challenging but there are software programs on the market that can essentially eliminate these hurdles. Keeping accurate time is another issue since Public Safety requires far more accurate time than currently expected in the traffic management function. This hurdle can be eliminated if the traffic management function utilizes the time keeping devices used by Public Safety and a software patch is installed that links the time keeping algorithms of the two data bases.


SUMMARY

To implement the interconnection certainly raises challenges in both the operational and technical arenas but it is not the technical problems that have to be solved but rather the operational issues that raise the most emotion. This is because the interconnection, as a minimum affects two (or more) different agencies within a jurisdiction and, in most cases, affects several agencies within different jurisdictions. 

When a system is proposed that will tie two or more jurisdictions together, jurisdictional autonomy issues are generally raised and since many of the ATMS are run by a state agency and most Public Safety dispatch is done at the local level, there is an automatic insertion of autonomy issues.  This is not to say these are not improper concerns because of the issue of liability. There is an understandable desire to not unnecessarily expose any agency to liability for the actions of another.  This hurdle can be overcome but it does take work in the area of Intergovernmental Agreements. Generally speaking success has been found whenever an agency is assured that data it makes available for transfer will be protected as if it were still in the home data base and if the functions to be temporarily assumed (transferred) must be done and if the performance of these functions does not increase exposure to liability.

There is a bit more concern when dealing with the law enforcement element of the Public Safety community since their information privacy needs are far more stringent than most other governmental functions. There is a fair amount of emotion surrounding this issue from law enforcement officials. By the same token, most traffic managers do not want their system's assets being used for law enforcement. Technology can solve both of these issues and while they are certainly points that must be addressed, both can be accomplished fairly easily to the satisfaction of all.

Normally there are significant procedural differences among the various agencies. This too can be overcome by recognition of the sanctity of the internal operation of each individual system. Commonality has to occur at the seam. We have found that by addressing it at the point where the two systems touch we produce the minimum internal disruption to the current operation.  This makes the entire interconnect program far easier to implement.

There are two areas that are more difficult to overcome. In the vast majority of state and local jurisdictions, the budget structure is separate for Public Safety and Transportation Management.  This may place improvements or implementation of ITS in direct conflict for limited budget dollars. Absent a strong information campaign about the value of interconnection, my belief is that Public Safety will dominate for it is a very visible item to the voting public and thereby to the politicians who approve the spending allocations. Not an easy hurdle to overcome but it can be done.

From the technical perspective, it is becoming ever easier to accomplish this melding of systems since there is an increasing availability of both hardware and software specifically designed to facilitate such an interconnect.  While the "voice" interconnect is almost a technical non-challenge, the exchange of "video" and "data" does require a bit more of a thought process and the development of a technical architecture that lays out the communication design, the translation devices (black boxes at the interconnect) and the appropriate software translation products.

On occasion there will be a system in which the intra-system communication capacity was not sized to handle this inter-system flow. There are several ways to address this ranging from compression of CCTV images to piggybacking on the local cable TV franchise network. Short form - although most new ATMS are being built with an eye toward accommodating this lateral transfer of video, data and wireline voice, there can be shortfalls in the ability to transfer wireless voice.  This is being addressed as new radio systems are installed particularly by those utilizing the 800MHZ trunked technology.

So what is next? There are a number of efforts underway to standardize. From message sets to communication protocols and hardware specifications, there is more and more of a focus on commonality. This will pay great dividends and markedly ease the establishment of the interconnect.

That there is movement in this area is attested to by the success in San Diego where agencies have gone so far as to establish common procedures, communication channels and have standardized on their inter-system message sets. In Detroit, the Michigan State Police have chosen to co-locate in the transportation management center. Similar programs are in place in Houston and San Antonio. In Cincinnati, mile markers emplaced by the transportation management system have markedly improved the efficiency of the Public Safety dispatch system and the implementation of a traffic information telephone number has produced as much as a 40% reduction in the number of 911 calls.

And this is just the tip of the spear. More and more of the procurements for establishment or modification of an ATMS are specifying a requirement to interface with the public safety systems and the public safety agencies are becoming a part of the selection board process. Recent examples are for procurement for ATMS in Denver and VDOT's Suffolk District. 

A public information campaign discussing the "goodness" of the combined system will help overcome some of the bureaucratic inertia that can be an impediment to putting the systems together.


CONCLUSION

Given the mutual dependence of the public safety agencies and those responsible to manage the transportation infrastructure when addressing incidents and congestion, it is imperative that the two systems be electronically interconnected to rapidly exchange voice, video and data. This is not a difficult task from a technical perspective. It can be done if desired. And everyone benefits.