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Effectiveness of Safety and Public Service Announcement Messages on Dynamic Message Signs

Chapter 2. Organizational and Institutional Frameworks for Safety and PSA Messages in the Four Urban Areas

This chapter identifies the organizational and institutional frameworks that govern the display of safety and PSA messages on DMS in each of the four urban areas—Chicago, Houston, Orlando, and Philadelphia.

Chicago

In Illinois, jurisdiction over the creation and display of safety and PSA messages lies at the state and local levels. Typically, safety messages and PSAs will originate at the state level, while travel times, incident notifications, and construction notices will be generated at the local level.

The Illinois Department of Transportation’s (DOT’s) Division of Traffic Safety, the State Secretary of Transportation, and the State Police all contribute to generating safety messages for display on DMS. The Secretary has insisted that the DMS show a count of highway-related deaths at all times, in addition to any travel times, incident notifications, construction notices, safety messages, and PSAs. The State Police and Division of Traffic Safety collaborate to create a list of safety messages and PSAs for display, usually corresponding to events of local or national significance. These messages are reviewed for conformance to the Manual on Uniform Traffic Control Devices (MUTCD).

Over time, the usage of DMS has grown from solely displaying travel times to posting safety messages around holidays or other events associated with high traffic volumes, to now showing PSA and safety messages, travel times, and a count of highway-related deaths. This three-phase message set is displayed continuously.

Moreover, the messages are displayed on all DMS in the Chicago area. There is no targeted demographic group; rather, the safety and PSA messages are aimed at the general traveling public.

During an interview with an Illinois DOT representative, it was not specified how the capital, operation, and maintenance costs of Chicago’s DMS are funded. Presumably, these costs are covered through a combination of state and local funding.

Houston

In general, safety messages are developed at the state level and then provided to regional TMCs for local dissemination at their discretion, based on traffic and other conditions. The development of the messages is based on Federal Highway Administration (FHWA) and state guidelines, and in part on national safety campaigns, while the localities have some feedback and input on which messages should be displayed.

Specific standards and guidance on DMS usage in the state of Texas can be found in Chapter 2I of the Texas MUTCD, 2011 version. Topics include applications, legibility and visibility, design characteristics, message length and units of information, and installation of permanent DMS. In general, the messages must be clear, concise, and easily understood by the public. 

Furthermore, the Texas Department of Transportation (TxDOT) primarily uses DMS for managing travel, controlling and diverting traffic, and identifying current and anticipated roadway conditions. Changes in roadway conditions include those due to traffic incidents, weather, and construction. Normally, TxDOT does not display messages that are basic traffic laws or could be considered “rules of the road.”

Travel times, construction notifications, emergency messages, and incident alerts have higher display priority than safety messages. During rush hours, only travel times are displayed, except for about 30 DMS on non-peak flow lanes that display safety messages. Outside of these times, and barring any incidents or construction, safety messages and PSAs are displayed continuously on all DMS in the Houston area. Usually, DMS are located sufficiently upstream of known bottlenecks, high crash locations, and major diversion decision points.

Also, non-incident, traffic safety messages are displayed on a limited basis and must be associated with a specific targeted safety campaign. Non-traffic-related safety messages such as “Click it or ticket” and “Don’t drink and drive” are displayed in conjunction with a media campaign. TxDOT has developed media tools for its traffic safety messages for use in television, radio, print ads, or news releases. These can also be part of national safety initiatives with support from the USDOT such as “Click it or ticket,” work zone awareness, and “No phone zone.” Through discussions with TxDOT, it was not clear how the construction, operation, and maintenance of DMS are funded, nor if the messages are targeted toward certain demographics.

Orlando

The display of safety messages is largely controlled at the state level, with some coordination with national safety campaigns. All messages displayed are for traffic information dissemination purposes. Due to a large number of requests, the state has developed guidance on safety and PSA message display.

The default display on DMS is travel times, but this can be preempted by other messages conveying information on emergency events, traffic incidents, law enforcement alerts, or special events. In the absence of accurate or useful travel time information, and when not preempted by other messages, the DMS will display a safety message or PSA.

As a compromise, safety messages are now shown in a limited fashion—presuming they have a positive effect on highway safety and congestion and the message is supplemental to a national or statewide highway safety media campaign. The total duration of any such campaign is limited to 2 hours per day during off-peak hours for a maximum duration of 2 weeks. Only six such events are allowed per year. The safety messages are posted to a select group of DMS deemed acceptable by the Florida Department of Transportation (FDOT). There are 18 DMS throughout the Orlando area, and local discretion is allowed for determining when to run the messages outside of peak hours.

Funding for construction, operation, and maintenance of the DMS in Florida is provided by the state, with no federal contributions.

Philadelphia

Control of the development and broadcast of safety messages occurs at the federal, state, and local levels in Pennsylvania. The state has issued formal guidance on this topic, Dynamic Message Sign Operating Standards, published in December 2013. The stated intent of the document is “to create uniformity in DMS messaging across Pennsylvania, yet provide flexibility for local needs.” Districts are encouraged to adopt these standards into their TMC’s standard operating procedures and develop pre-planned DMS response plans based on recurring events.

Numerous sources were used by the Pennsylvania Department of Transportation (PennDOT) to develop the standards, including the national MUTCD, other state DMS guidelines, FHWA reports and directives, user comments, and the TMC PFS Changeable Message Sign Operation and Messaging Handbook.

PennDOT ’s engineering district offices have the ultimate responsibility for the operation and dissemination of messages via DMS on roadways within their jurisdictions.

The state recommends prioritizing messages in the following order:

  1. Full road closure.
  2. Roadway restriction.
  3. Emergency destination guidance.
  4. AMBER alerts.
  5. Congestion.
  6. Weather/road conditions.
  7. Automated intelligent transportation system (ITS) messages.
  8. Special events.
  9. Future/planned events.
  10. Scheduled safety messages.
  11. Travel plaza messages.
  12. Sign testing.

Travel times may be displayed in a two-panel fashion with any of the other types of message priorities listed.

Furthermore, particular guidance is provided for scheduled safety messages. The display of such messages may only be for a limited basis, is prohibited during peak traffic times (weekdays from 6am to 9am and 3pm to 6pm), and can only be on DMS under the direct operation of district TMCs. All safety messages must be posted in accordance with the Scheduled Safety Message Calendar developed by PennDOT Central Office. Unless a DMS is being used to display a higher priority message, safety messages must be displayed on at least 50 percent of DMS. If the need arises, a District Traffic Engineer (DTE) can request an exemption to run a customized Local Safety Message in conjunction with the safety message calendar.

Approved safety messages and a schedule for display are generated and distributed to the district TMCs each January. The four categories of safety messages include:

  1. Messages for a statewide safety campaign.
  2. Messages particular to a locality or region, which require DTE and Central Office approval.
  3. Messages in support of a new or existing traffic law, which must be vetted by the State Press Office.
  4. Messages on weather-related traffic laws.

Also, the display of general PSAs is prohibited on DMS, along with messages related to advertising, routine congestion, contact information, and chronological information.

Moreover, the interview with DOT staff in Philadelphia revealed that scheduled safety messages are displayed continuously at strategic locations during safety messaging operations campaign periods. Such locations may be after entry points with high traffic volumes.

Funding and targeted demographics were not discussed during the interview with the PennDOT staff.

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