to Political Tradition. ROGER W . RElNKE. Abstmct-Elelen years of 911 universal emergency telephone number implementation have resulted in on11 limited ...
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EMS Public Access Through911: A Technological Response to Political Tradition ROGER W . RElNKE
failure to deal with political realities would make shambles of most EMS plans. In the political context, these “realities” are derived from policies, usually undocumented and of ambiguous origin, that reinforce functional autonomy and authority, and deny greatermanagementflexibility.Apremise:byfacilitating removal ofcertainpoliticalobstaclesthroughtheintelligent application of 91 1 technology, worthwhde improvements in EMS and other public safety response will be made. The advocacy of a technological solution to political problems is not undertaken lightly. Nor is it implied that consolidation of communications facilities (or even functional conLONG WITH SMOKERS, alcoholics, atheists, and others solidationitself) is unworthyofconsideration as away to who have reformed, found nirvana, and are now bent on overcomejurisdictionalsensitivities.It is truethatthetechproselytizing,peoplewhourgeimplementationofthe 91 1 nological solutions are probably more expensive than the cost emergency telephone number may surmise that their pleadings of negotiation, compromise and agreement. arefalling on unsympatheticears.Such isusually the case. Eleven years after the AT&T announcement of the availaRegardless of theappealof911 service anditsefficacyin bility of 91 1 as auniversalaccess code, 74 percent of the diverse,traumaticincidents.thedoubtersarenotmovedto nation continues to dial anarrayof sevendigit numbers or make changes. “0” for operator. The rate of 91 1 installation has been slow, In the face of evident apathy, 91 1 supporters can seek conbut steady. It appears that a good many installationshave been solationinthesharedexperienceofhealthsystemplanners made in places where there was close correspondence between and others who try to improve the way in which public safety city or county limit lines and telephone exchange boundaries. services are performed by government. Typically, there may be Or, for reasons unrelated to 91 1, joint agreements covering someminordisagreementaboutthetechnicalaspectsofa radiodispatching or other services existedamong or inarea problem, but the real challenge is achieving change in what is jurisdictions that made 91 1 installation a straightforward, nonbest described as the political environment. In the case of 9 1 1, controversial service t o be included. with independent functions involved, the problems are at once The 91 1 implementationproblemsnowbeforestateand technical and political. and further compounded by the overlocal governments will require much more comprehensive planlappingactionsofthetelephonecompanies. EMS advocates ning if they are to be resolved. It is time to regard 91 1 not have no monopoly on frustration. merely as a convenience t o those stricken people who cannot The local political environment bears directly on the greater recall or look up seven digit numbers under stress, but rather availability of 91 1 service. Public access through 9 1 1 ought to as an important means to bring about a more rational public be available without regard to the niceties of city limit lines or safety service delivery process. other artificial barriers of no immediate concern to the victim The ubiquitousness of the telephone and the proclivity of seeking help. Universality of access will not be accomplished, people to use it to summon help suggest that the role of the however, until many obstacles are removed. telephone would be a significant part of emergency communiThis observation applies equally to the whole spectrum of cations planning and research. In fact, not nearly as much atproblems of EMS system planning. implementation, and operatention is given tothewaysinwhichpeople perceive and tion, of course. One needonly review the IEEETRANSACTIONS report emergency situations as is given to complaint processing O N VEHICULAR TECHKOLOGY issue ofNovember,1976,the withinagencies,medicalcontrol,biomedicaltelemetry,full firstdevoted to EMS communications. to bepersuadedthat channel capability, and other components or techniques which may be of limited applicability. Manuscript received June 30, 1979. The lack of rigorous analysis of emergency calling behavior The author is with the National Telecommunications and Informais due probably to the common assumption that almost everytion Administration, Room 296, 1325 G St..N.W.,Washington. D.C. one encountering a situation apparently calling for emergency 20005. Telephone (202) 724-3349. Abstmct-Elelen years of 911 universal emergency telephone number implementation have resulted inon11 limited availability of the serbice across the country, although it is highly successful in well-managed systems. Further implementation, especially in urban areas, depends on telephone companypolicy and willingness of communities to participate in joint facilities, or to invest in expensive technologq to automatically route service requests to the proper jurisdiction. Political decisions regarding technology application will play a critical part in future implementation. The National Telecommunications and Information Administration (STIA) and other Federal agencies seek to encourage both cooperative efforts and the debelopment of affordable selectibe routing capability for 9 1 1 services.
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U.S. Government work not protected by U.S. copyright.
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response will: resolve t o call some agency;l know the location of the incident; discriminate between an emergency and a nonemergency situation. as defined by the response agency; determine how best to place a call. especially in unfamiliar environments, and be physically and mentally capable of dialling seven digits under varying circumstances; pursuethedecision t o reachanactionagency,even if referralsarenecessary and/or changeforapayphone must be found; respond positively and informatively to interrogation as to the nature and location of the incident, and consent implicitly or explicitly to become “officially” involved. Theassumption is unfounded. Individuallyandaggregately, the behavioral factors noted above can influence in important waystheprovisionofassistance,andeventhedecision to make the call in the first place. Injustifyingthestatusquo,systemmanagersandothers may claim that their sevendigit emergency numbers are well known to the community, and 91 1 offers no greater advantage. A study directed to investigation of 265 EMS calls at the site of occurrence produced this observation: “It was also interesting tonotethat in Columbus [Ohio],wherea well-established systemexistsanda seven digit access number has been advertised for a long time,93percent of the calls wereenteredby dialling ‘O”’[ 1 I . The State of New York’s Department of Public Service, in a report of the regulatory agency’s study of 91 1 service, noted that: “The New York City Police Department once employed a seven-digit number for emergencies. The number (4401234), common to all boroughs. was well publicized and easy tolearn,butonly 35 percent of the calls they received were dialled directly, the remainder being forwarded by telephone company operators. In contrast, 97 percent of their 17 000 daily calls today are received directly through 91 1”[ 21.
If less is heard these days from advocates of “common” seven digit numbers or the use of “0” for operator, more arguments are made that emergency response time will not be reduced in 911systems,butactuallymaybeincreased;andthat call volumes on 9 11will be unmanageable. The call volumeconcern,thatnew91 1 systemsusually experience an increase in calls reporting emergencies, is legitimate. Increases are reported beyond the normal workload projections.Itappearsthatmanyemergenciesweresimplynot reported in the past and that more reports of the sameincident are being made. The latter factor is capable of measurement, but the formeris more subjective. 1 This is the critical decision in many instances. The “Kitty Genovese” rationale may be governing: that in a public place, with witnesses present, “somebody else” will take the notification initiative.
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A recent report issued by the California Legislative Analyst, prepared in response to moves in the California legislature to repeal mandated 9 1 1 service (California being the first state to requireitscommunities t o install 911bya specificdate), makes the following observations: “Any tangible benefits from 91 1 depend on the extent towhich(1)911shortens responsetime(thatis,the time between when an emergency occurs and when help arrives) and (2) the shorter response time (if any) results inmore lives andproperty saved andmorecriminals apprehended. No data areavailable whichdemonstrate that 9 1 1 shortens emergency response time and provides tangible benefits. Thus, support for 9 1 1 is based on individual, publicized cases and on supposition, rather than on hard evidence.” [ 31 . In a chapter purporting to clarify “Fact Versus Opinion,” the report notes that: “Despite the lack of evidence documenting its benefit, 91 1 enjoys great popularity .... Our own survey of officials in 20 communities with 9 11 systems confirmed the divergency of factandopinionregarding911. While a large majority of respondents expressed the belief that 91 1 provides a benefit to the public, none was able to support this belief with data.” [3, p. 351. Curiously, the report rests its recommendations on its analysis of 20 surveyresponseswhicharedescribedasopinions,and concludesthat,althoughopinionsarefavorable t o 9 1 1 , because no data exist, 91 l:
“... is not likely to have asignificanteffect onemergency response time for three reasons: 1 . Itcanaffectonlyalimitedportion of thetotal time involved in responding t o an emergency. 2. Thatportion ofresponsetimewhichcanbeaffected by 91 1, although not subject to measurement, is likely to be small. 3. The potential time savings offered by a 91 1 system may not be realized.” [3, pp. 35-36]. Thispeculiarrationalization,alongwiththeassertionthat “The fact that a large percentage of callers already knows the proper number to callin an emergency casts some doubt on the overall benefit of 91 1” [3, p. 421 is not convincing. In the absence of data, it is just as convenient t o reach opposite conclusions.Thereport suggests thatotherremediestolong response time ought to be examined, such as the addition of police, fire, and EMS personnel, and the installation of computerized dispatching, on the basis that they would be more cost effective. The reduced response time justification for 9 1 1 is attacked bythosewhofeelthatanyreductionattributable t o itsuse accountsforonlyaninsignificantproportionoftotaltime betweenperceptionofneedand arrival on the scene of the actionagency.Isimprovedresponsetimeworththecostof 91 1, or any other personnel or technology investment? The
REINKE: EMS PUBLIC ACCESS THROUGH 9 1 1
Kansas City Response Time Analysis revealed that “,,. reporting time was longer than either the time taken to dispatch a call or the time taken totravel t o a call and nearly as long as the combined time taken to dispatch and travel to a call. Response time was found t o be unrelated to the probability of making an arrest or locating a witness for the large proportion of Part I crimes that were discovered after the crime had occured.” [ 4 ] .
There are other factors in the term “reporting time” that must be noted in this context, not the least of which is the perception of thecitizenregardingpoliceassistance.Also,thecity does not yet have 9! 1 service. The Kansas City report notes that response time is not very important for incidents after they have occurred. Since crimes in progress are reported in much smaller numbers, the justification question is difficult to answer. (Some data did emerge in Kansas City, however. In that city, 38.7 percent of calls were made to the well-publicized, seven digit number; 28.6 percent to the police administrative number; and 3 1.2 percent to the telephone company operator [4,p. 1011 .) As is true for crimes-in-progress calls, the critical EMS incidents are only a small fraction of all emergency runs. “Based upon preliminary aggregate analyses, the proportion of critical patients for whom survival appears to be highlysensitive tothetreatment delaymayrepresent less than 15 percent of all critical patients. The subpopulation of highly time critical patients, therefore, may be as small as 1/10 of 1percent of all emergencydepartment patients. About 90 percent of this subpopulation survives when restorative interventions are administered within minutes of the onset of criticality. On the other hand,the survival rate of thissubpopulationalso falls sharply when early treatment is not provided.” [ 5 1. Finally, the number of fire emergencies are typically a small part (1 0- 15 percent) of all public safety emergency response in a jurisdiction. Thus the proportion of incidents of all types of a truly critical nature is a very small part of total workload. The problem is to determine if investments in technology are justified on this basis. Harddatadescribingresponsetimeresultsof911implementation would be very desirable. In like manner, hard data in regard to the number of lives saved by basic and advanced life support systems would be useful in determining cost benefits, if anagreeablevaluecanbeplaced on human life.Researchers are attempting t o generate these kinds of data, but in the meantime, subjective judgments must be made. To the extent that these judgments are based on actual experience, they have merit. California’s legislative concerns about the costs and desirability of mandating 91 1 service are obviously shared by jurisdictions that currently decline to proceed with 91 1. z A certain 2 In mandating 91 1, the Legislature provided implementation funding by means of a tax on intrastate telephone service. The current problem is one of apportioningandcontrollingthisfund. While it is certainly appropriate to question what is being funded, and if it is in the public interest to do so, the findings of the Analyst stand in stark contrast to those of 91 1 users.
269 proportion of these places have no choice. They cannot proceedbecauseoftelephonecentralofficemodificationproblems,particularly in olderofficeswithoutcommoncontrol equipment. A larger proportion (regretfully, there is no accurate estimate of these proportions) is unable t o reconcile thepoliticaljurisdiction/exchangeboundarymismatchproblem. The reasons articulated for nonimplementation are many, but over 700systemsthusfar have donesomeproblem solving, apparently in the belief that even a few more successful resolutions of critical, life-threatening situations are worth the effort. It is difficult enough to obtain agreement among functional agencieswithinajurisdiction,much less extra-jurisdictional agreements, as tohow911 calls will behandled.Inmost places, however, a mayor, city manager, or county board can take actions which will lead to 91 1 service within thejurisdiction without threatening functional integrity. Thechallengenow is achievingmultijurisdictional91 1 service when all shared facility arrangments are rejected. When multiple complaint processing facilities throughout an area are indicated, selective routing of 91 1 calls has the appeal of protecting jurisdictional autonomy and thereby helping to overcome some of the political obstacles. Selective routing refers tothe abilityofthetelephonenetworktoautomatically switch 911 calls to the jurisdiction responsible for service to the caller’s location. Onitsface,preservinglocalautonomythrough selective routing will encourage a more rapid rate of 91 1 implementation (if the technique is affordable by users). That incentive, however,may have detrimentaleffects,according to some EMS experts, because it favors continued fragmentation. and not a coordinated regional response system [ 6 ] . Inpractice,coordination is morelikely tobe achieved through selective routingthanthrougharegionalsystemimposed from without. As long asagenciescanmaintainsome direct control over their workload demands, they will be more receptive t o sharedresourceallocationdecisions.Fromthe perspectiveof thetaxpayer,thecommunityshould be in a position t o establishandimplementitspoliciesin regard to public safety response to its citizens as it sees fit. The logical time and place t o exercise control is when and where a request for assistance is first received. If the request meets the community’scriteriaforresponse,theactualdispatchingcantake place within the community, at a regional coordination facility, or both. Unfortunately, the appeal of selective routing as a means of preservinglocal autonomymay discourageefforts t o implement 91 1 through the shared facility approach. The justification offered for delay is that selective routing capability will be within reach shortly. About 38 percent of all Bell System central offices are now of the electronic type [7]. They are very likely to be in more densely popu!ated, multijurisdiction areas.However, thecostsoftrunking,terminalequipment, and all the other components of 91 1 systems may be substantial, without regard to the availability of electronic switching in the service area. There are currently five selectivelyrouted9 11 systems in
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service.Threedependonelectronicswitching.3Theyare Thescarcitythusfarofselectivelyrouted 91 1 systems Alameda County, CA; Chicago, IL (only for dispatching purmakescostanalysisdifficult,because so fewtariffscovering poses within the City); and Dade County, FL. the servicehavebeenfiledandapprovedbystateregulatory The fourth, through an ingenious application of a common agencies. The “special assembly” basis for current or proposed telephone engineering practice, selectively routes calls t o either tariff filingsconfirms the lackofsystemstandardsforthe the City of Punta Gorda or Charlotte County, FL. Because a technique. Bell Laboratories has developed an 8A key system choice of only two answering points is involved, the United especiallyforregular911application(noselectiverouting), Telephone Company decided to use class marking (sensing a but there appears to be remarkable differences among tariffs call with a diode) in the single electronic processor-equipped filed forthesame8Aequipmentinvariousstates.NTIA is currently analyzing both fded and proposed 911 tariffs to help crossbar exchange serving the city. The total conversion cost paidby the two jurisdictions was $9083 plus a $3000 labor regulatory agencies carry out their responsibilities more effectively. charge, or slightly more than one dollar per main station teleThe mix of political sensitivity, regulatory concern, funcphone in the city. tionalintegrity,andtechnologicalapplicationresultsinthe Thefifthsystemalsousesclassmarkingtoselectoneof kind of situation at the local level that demands committee two answeringpoints.TwocentralofficesinGeneralTeleto achieve 91 1 service. A local “ramrodphone’s L o s Gatos, CA, service area overlap county boundaries, or task force action der” can be quite effective in certain places, but the complexwith about 1125 lines affected. One office with computerized itiesinothercommunities still exploring 9 11aresuchthat switching waseasilymodifiedatacost of $137. The other, using step-by-step equipment and a type 101 director, required even individual system managers of the established emergency services are reluctant to take a leadership role. hard wiring at a cost of $5300. Total monthly service charges At the Federal level, the EMS Communications Interagency for 91 1 switching are about $234. Class marking appears not Work Group designated a 91 1 Task Force in December 1977. to havebeenused to date t o switch 91 1 calls foragencies The primary purpose of the Task Force, chaired by NTIA, is served by the Bell System. to coordinate and stimulate the Federal mission agency proAs ESS officesareinstalled,replacingamortizedequipment, central office conversion to accommodate the digits 911 grams that include 91 1 as a component. Agencies participating are DHEW/EMS, DOT/NHTSA, the Law Enforcement Assistshould become less expensive. An important element in total system cost is the creation or modification of the data manage- ance Administration, the Departments of Labor and Agriculture (REA), the FCC, and the new Federal Emergency Manmentsystem(DMS).Becausemultijurisdictionsareinvolved, agementAgency(FEMA).TheTaskForceplannedtheNaall main stations must be identified as to responsible jurisdictional 91 1 Conference, published suggested state 91 1 legislation, not post office or other locators suitable for telephone tion with an analysis of existing 91 1 legislation, and has condirectorypurposes.With service orderprocessing,updating tinuedtomeetwithtelephoneindustryrepresentativesand and file maintenance added in, the DMS maybecomequite others in working out ways to expand 91 1service availability. expensive. TheInteragencyWorkGroup is concerned as wellwith The methodology of exchange conversion and DMS maintenance, however, should be a part of standard telephone engi- communicationsafterthecitizenhasgainedaccesstothe responseagency.Theestablishmentofbiomedicaltelemetry neering practice, so that redundant, useless expenditures are standards is one of the more notable accomplishments. avoided. At a National 9 11 Conference convened by NTIA in Minneapolis in May, 1979, panelists from St. Louis and Kansas Current activities are directed t o attaining the common system City both noted the proportionof DMS and other costs simply approach called for in the Federal Communications Commission’s Docket19880,preparingthe EMS Communications described as “systemdevelopmentcosts”inestimatesfor TechnicalPlanningGuide,furtheringjointfundingopporselectively routed systems in their cities. The apparently high tunities,andgenerallyaddressingwaysinwhich EMS comproportion (over 50 percentofthetotalestimatedsystem munications can facilitate the EMS mission. It is an important cost) was noted by others contemplating selective routing in mission, one that may require modification of individual and the sameoperatingcompany’sterritory. As aresult,system corporate preferences in order to achieve greater benefit for planners and NTIA have challenged the estimates; at least two more people. substantial, downward revisions are being made. Automatic identification of the calling number (ANI) and REFERENCES theassociatedlocationaddress(ALI)aretwofeaturescomG. B.Keller and M. D. Keller,“Epidemiologicstudies in EMS systems,” NCHSR Res. Proc. Series, 1978 ( D E W Publication (PHS) monlyconsideredatthetimeselectiverouting is explored. 79-3233), p. 25. WithANIandespeciallyALI,additionaldatarequirements L. A. Ceddia, ‘91 I ’ A staffregulatory viewpoint of the universal mean greater costs, even though in most urban areas the calling emergency telephone number,” Stateof New York Departmentof Public Service, p. 41, May 15, 1973. number is routinely displayed for toll operators. Both are very Legislative Analyst, “An evaluation of the mandated statewide attractivefromaresourcedispatchingviewpoint, but cost emergency telephone number (91 1) program,” State of California, May, effectiveness remains to be proven. 1979, p. 9. ”
3 No. 1 or 1A officewith IE5 orIAESgenericprograms,orlater models: Chicago’s systemusestelephonecompanyownedminicomputers to perform call routing.
Board of PoliceCommissioners, Kansas City, MO, “Response time analysis,” Vol. 11, 1977. p. iii.. R. B.Andrew, “Treatment and outcomes for criticalpatients.“ EmergencyMedicalServicesSystemsResearchProjects, NCHSR Research Management Series, 1978. p. 8.
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The Mobile Relay as Applied to the North Carolina Medical Communications Network CARL C. VAN COTT
Abstract-The UHF Mobile Relay Radio Station as itis applied to emergencymedical service (EMS) communications systems in North Carolina is discussed. The system design concept, evolution, and rationale are developed. Systemequipment configurations and compatibility factors are determined as they relate to operational systems. Operating system models and diagrams arepresented and analyzed.
BACKGROUND
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ARLYbiomedicaltelemetrysystems(circa1967-1968) were developed to allow responding field medical teams to communicate voice information and transmit biomedical data (usually theelectrocardiogramorEKG)toaphysicianat a hospitalormedicalfacility.Theseearlypioneeringmedical telemetry field teams had close medical supervision and were frequentlyapartofanexperimentalhealthresponsemechanism.Thesystemswereoftenoperated by afiredepartment, rescue squad,orambulance serviceworking in close cooperation with a physician.Thefieldmedicalunitswould respond within a limited geographic area, typically a portion of a city that could be responded t o conveniently by a single mobile unit, and could be easily provided with radio coverage from a single base station, commonly located at the hospital. Radio and telemetry equipment for these early systems were suppliedfromalimitednumberofmanufacturingsources? with the medical electronic equipment packages supplied separatelyfromtheradioequipment.Thetelemetrysystem suppliedtotheseearly field teamstookmanyforms,consistingof an EKGamplifier-modulatorpackage,amedical Manuscript received June 11, 1979. The author is with the Office of Emergency Medical Services, State ofNorth Carolina, P. 0 . Box 12200, Raleigh, NC 27605. Telephone (919) 733-2285.
display-defibrillatorpackage,andatwo-wayradiounit.The field team would additionally carry a drug box and other necessary rescue and medical supplies. Various equipment configurations were used ranging from field portable devices including walkie-talkietyperadiostosuitcaseportableequipment,or telemetry units totally dependent on the mobile radio installed in the ambulance or transportation vehicle. These early field responseteamsbecametheforerunnersoftoday’saccepted advanced life support paramedic teams. Radiofrequenciesforoperationoftheseearlysystems spannedtheentireradiospectrumfromlowbandVHF through UHF. Systems were licensed with the Federal Communications Commission (FCC) as developmental in the Local Government Radio Service. Fire Radio Service, or SpecialEmergencyRadioService.Somesystemswereoperatedon businessfrequenciesorcommoncarriertelephone systems.Therewas no clearlydefinedradioserviceallocationfortheoperationofthesefieldtelemetryunitsuntil FCC Docket 19261 in June of 1971. Thisdocketmadeavailableforthefirsttime five pairs of UHFfrequenciesfornonvoicecommunicationdevices. As theseearlyparamedicsystemsbecamefullyfunctional,their communicationneedsandrequirementscould be betterdefined and thus equipment was refined and methods of operation improved. The first major advance in the telemetry equipment was the developmentoftheduplexed field portable radio. This equipment allowed for simultaneous transmission and reception at the paramedic’s location. This was desirable as it allowed the paramedic to continue to transmit information to the physician or hospital and at the same time receive instructionsfromthephysician.Thephysiciancouldinterruptcommunicationfromthefieldto give instruction, ask
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