Behavioral Traffic Safety Messaging on Variable Message Signs (2022)

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P A R T 1 Guide

1-3   Many transportation agencies own and operate variable message signs (VMS) (also referred to as changeable, electronic, or dynamic message signs). These signs are a useful tool for providing future and real-time traffic management, operational, regulatory, warning, and guidance informa- tion to drivers. In addition, many agencies use these signs to display behavioral traffic safety (BTS) messages. Practices vary significantly from agency to agency as to the topics of the safety messages, how the messages are formatted, and when and where such messages are displayed. Figure 1 lists some of the BTS topics that agencies have incorporated into VMS messages in recent years. Studies indicate most motorists think that displaying BTS messages on VMS is a good idea when the signs are not needed for conveying traffic management information (see Rodier et al. 2010; Boyle et al. 2014; Mitran, Cummins, and Smithers 2018). However, it is important to remember that VMS are traffic control devices and so are governed by the standards, guidance, and options specified in the Manual on Uniform Traffic Control Devices (MUTCD) that is owned and main- tained by the FHWA. As noted in the MUTCD, effective traffic control devices adhere to five fundamental principles (MUTCD 2009). Specifically, such devices • Fulfill a need; • Command attention; • Convey a clear, simple meaning; • Command respect from road users; and • Give adequate time for proper response. VMS message design involves both traffic engineering and human factors considerations. These considerations dictate the acceptable length of the VMS message, what information is included in the message, and how the message should be formatted on the VMS. The MUTCD includes standards and guidance for designing and displaying traffic management messages on VMS. Part 2 of the MUTCD also provides information about the design and display of BTS messages on VMS, although it is less detailed than that for traffic management messages. Need for the Guide For messages providing traffic operational, regulatory, warning, and guidance information (i.e., traffic management messages), proper message design is based on the concept of “units of information.” In these types of messages, each information unit is an answer to a specific ques- tion. Messages are designed so that drivers operating their vehicle can read and remember each unit of information presented, make a correct driving decision based on the information, and execute the required driving action(s). Research has shown that most drivers can only remember and use four units of information at a time for these types of VMS messages, equal to approximately eight words (Dudek 2006). C H A P T E R   1 Introduction

1-4 Behavioral Traffic Safety Messaging on Variable Message Signs While useful for traffic management messages, the concept of information units does not work very well when designing BTS messages for VMS. The display of BTS messages on VMS is often part of an overall road safety campaign. Typically, drivers do not need to be able to remember all the words in a BTS message. Rather, drivers need only to correctly recognize the safety topics of the message and understand the appropriate driving behavior or action that is stated or implied in the message. Nevertheless, BTS messages must still be designed to be quickly and accurately interpreted by drivers within the limited time that a message is visible to a driver approaching the VMS. Therefore, this Guide has been developed to • Assist message designers in the creation of acceptable BTS messages and • Assist VMS operators in developing good message display policies and practices (when to display, how long to display, how often to display, etc.). Organization of the Guide This Guide was developed to assist practitioners in the design and display of BTS messages on VMS. It was developed from a review of the literature and with input from practitioners in the field. It provides a summary of the fundamentals that influence good BTS messaging, guidance in BTS message development, and examples. Information in the Guide is based on the following: • Results of past human factors studies. • Additional human factor studies performed under this project. • Traffic engineering principles. Three types of information are provided in the Guide: • Fundamentals of BTS messaging. • VMS message design and operating principles for BTS messages. • BTS message display guidelines for VMS. In addition, Appendix A provides examples of BTS message phases from agencies across the United States that follow the principles presented in this Guide. BTS messages must be quickly and accurately interpreted by drivers within the limited time that the message is visible to a driver approaching the VMS. Seat belt use Drowsy driving Distracted driving Drinking and driving Driving in adverse weather Proper lane and shoulder use Child passenger safety Watch for children/back to school Speeding Giving large trucks more room Tailgating Traveling safely through work zones Motorcycle and bicycle awareness Move over law requirements Proper use of turn signals Share the road/driving safely Figure 1. Common safety topics of BTS messages on VMS.

1-5   Basic Concepts of BTS Messaging Road safety campaigns typically have one or more of the following goals (Delhomme et al. 2009): • Provide information about new or modified laws. • Improve knowledge and awareness of various driving risks and the appropriate preventive behaviors to mitigate those risks. • Change underlying factors known to influence road-user behavior. • Modify problem behaviors or maintain safety-conscious behaviors. • Decrease the frequency and severity of traffic crashes. Considerable social science, psychology, marketing, and outreach research has been con- ducted to understand how best to design, implement, and evaluate BTS messaging for road safety campaigns. Interestingly, the principles of good BTS messaging in a safety campaign are consis- tent with the principles for effective traffic control devices outlined in the MUTCD. As shown in Figure 2, effective BTS messages are credible, trustworthy, consistent, clear, persuasive (encouraging a behavior change), relevant, and attractive to the target audience for the messages. Figure 3 illustrates a five-step process for developing a BTS message that is most likely to lead to a positive behavioral change. The first step is to identify the target audience (drivers) for the message. Identifying the target audience for the BTS message is necessary to determine what motivates the target drivers to perform the undesirable behavior of concern and what would motivate them to change to a safer behavior. The message designer should strive to understand the beliefs, intentions, and habits of the target audience that serve as motivators for the undesir- able behaviors. Once the target drivers and their behavior motivators are determined, the message objective is selected based on what is desired for the target audience to know, believe, and/or adopt as a safer behavior. Based on this information, the message designer then defines the benefits that the safer behavior will have to the target audience in place of the problem behavior or the costs that continuing the problem behavior will have on the target driver. A message can then be developed to emphasize the perceived benefits or gains of adopting the safer behavior and/or to emphasize the additional costs or losses of continuing the problem behavior. Both benefits and costs can be expressed in quantitative and/or qualitative terms. Defining the Execution Strategy of a BTS Message Once the content of the message is determined, efforts turn to deciding on the message execu- tion strategy. The goal of the message execution strategy is to capture the attention of the target audience and encourage them to adopt the safer behavior. The execution strategy can be based C H A P T E R   2 Fundamentals of BTS Messaging

1-6 Behavioral Trafc Safety Messaging on Variable Message Signs on the dissemination of nonemotional facts or can use emotional appeals to capture the atten- tion and aect the intentions and habits of the target audience. Messages that use both types of execution strategies can also be created. Use of Facts and Data Past research suggests that the presentation of facts and data (such as the number of trac fatalities) in a BTS message does not consistently elicit a change in target audience attitudes or perceptions due to “optimism biases” where drivers assume they are less at risk than others, have a greater ability to control their risks, or both (Guttman 2015). In addition, disseminating facts pertaining to the amount of enforcement performed or the number of nes issued can lead target drivers to focus more on how to avoid getting caught than on changing to a safer driving behavior. Still, several agencies include safety-related statistics within their BTS messages (see Figure 4 for examples). E ective BTS Message Credible Trustworthy Consistent ClearPersuasive Relevant A ractive Figure 2. Seven characteristics of an effective BTS message (Delhomme et al. 2009). Identify Target Audience Identify Problem Behavior Select Message Objective Define Benefits of Safer Behavioror Costs of ContinuingProblem Behavior Develop Message Figure 3. Process for developing a BTS message (developed from Delhomme et al. 2009). 484 TRAFFIC DEATHS THIS YEAR CAR SEATS SAVED 122 LIVES IN 2020 BUCKLE UP LAST YEAR 2054 DUI ARRESTS IN PA Figure 4. Examples of BTS messages on VMS using facts or data.

Fundamentals of BTS Messaging 1-7   Use of Emotional Appeals Emotional appeals in a BTS message can be either positive or negative. As shown in Figure 5, positive appeal messages focus on what the target driver will gain by adopting the safer behavior, whereas negative appeal messages focus on what the target driver would lose by continuing the unsafe behavior. Both types of messages can be effective. However, negative appeal messages tend to have less of an effect on male drivers than on female drivers (Lewis, Watson, and Tay 2007). Use of Humor, Wit, or Pop Culture References in BTS Messages Considerable attention has been given in recent years to the use of humor (including witti- cisms, plays on words, pop culture references to song lyrics, quotable lines in movies, or current event topics) within BTS messages. On one hand, humorous messages tend to be fairly well- received by the driving public. In fact, there is some evidence that the use of humor can improve the influence of a BTS message on males (Lewis, Watson, and White 2008). On the other hand, excessively humorous BTS messages may entertain drivers without getting them to understand and accept the safety analogy being presented. In addition, messages that attempt to shame or label certain target drivers may not be effective, as those target drivers may not identify with those being mocked or insulted in the message. Finally, parodies and plays on words need to be familiar and liked by the target drivers to be effective. Negative appeal messages utilizing these features may be considered in bad taste or offensive to some drivers—even to the nontargeted drivers. Figure 5. Examples of positive appeal and negative appeal BTS messages that are well-formatted for display on VMS. Positive Appeal Messages Negative Appeal Messages SEAT BELTS SAVE LIVES DRINK DRIVE GO TO JAIL CLICK IT OR TICKET SLOW DOWN AND SAVE A LIFE STOP THE TEXTS STOP THE WRECKS DRUNK DRIVING KILLS KEEP SAFE DISTANCE STAY SAFE DROWSY DRIVING IS DANGEROUS Excessively humorous BTS messages may entertain drivers without getting them to understand and accept the safety topic being presented. Negative appeal messages that utilize parodies, plays on words, or that attempt to mock or shame certain drivers may be considered in bad taste or offensive to some drivers.

1-8 VMS messages that are too long or are confusing to drivers can create operational and safety problems. Understanding Drivers’ Capabilities for Reading VMS Drivers traveling along a roadway have only limited time to read and process a message that is being displayed on VMS. The amount of time available for reading a message depends on the legibility distance of the VMS and the speed at which the driver is traveling. The legibility distance of VMS messages depends on • Driver visual acuity, • Type of VMS being used, • Height of the characters used to create the message, and • Environmental conditions. Typically, VMS messages will be legible to most approaching drivers for about 8 seconds total when traveling at 60 mph (Dudek 2006). If operating speeds are higher or environmental condi- tions degrade visibility, less legible viewing time will be available. Although the message on VMS might be visible and legible to drivers for up to 8 seconds while approaching the sign, drivers typically do not (and should not) focus on the VMS message for the entire time that the message is legible. Rather, drivers multitask between glimpsing the VMS message, scanning other parts of the roadway, checking vehicle instruments, and operating the vehicle controls. Consequently, it is important that VMS messages be easily readable and immediately understood so that driver attention is not unduly diverted from the other driving tasks. If messages are too long or too confusing, drivers may slow down to give themselves more time to read the message or may miss other important visual stimuli in the driving environment while they focus more of their attention on the message. Such behaviors are undesirable and contribute to both operational and safety problems. FHWA Ruling Regarding BTS Messages on VMS On January 4, 2021, FHWA issued an official ruling, Uses of and Nonstandard Syntax on Changeable Message Signs (Kehrli 2021). The ruling was issued in response to questions regard- ing the use of unconventional wording in VMS messages and regarding public input into message development. Although not focused exclusively on BTS messages, much of the ruling pertains directly to such messages. As part of the ruling, FHWA encourages that the display of BTS messages on VMS be done as part of “larger safety campaigns that rely on other media as their principal means of com- municating the campaign message.” In addition, the display of such messages should be coordi- nated with enforcement efforts regarding the problem behavior. FHWA suggests coordinating BTS messaging with the National Highway Traffic Safety Administration’s (NHTSA) annual C H A P T E R   3 VMS Message Design and Operating Principles for BTS Messages

VMS Message Design and Operating Principles for BTS Messages 1-9   communications calendar (NHTSA n.d.) whenever possible to encourage consistency in behav- ioral safety outreach efforts across the nation. FHWA also encourages agencies to consider the type of roadway where VMS are located when selecting BTS messages to display. A message about watching for children as they return to school may be appropriate for VMS on an arterial street near a school, but less so for one located on a high-volume urban freeway where there is little chance of encountering children on foot. Some agencies have used contests or other means of soliciting ideas from the public for BTS messages to display on VMS. FHWA recommends that public input be primarily used to identify messaging ideas, with the responsibility for designing and formatting messages left to agency staff with knowledge of proper VMS message design principles. The FHWA ruling discourages the use of humor or wit, informal words and phrases (colloquialisms), and pop culture references as part of BTS messages over concerns that such messages may not convey clear and consistent meanings to drivers. The use of such expressions may also degrade motorists’ respect for the VMS as a traffic control device and can increase the amount of time it takes motorists to recognize and process VMS messages overall. Some of these concerns were validated during a human factors study of BTS messages performed under BTSCRP Project BTS-02 and documented in Part 2 of this report. In that study, fewer than 50 percent of the subjects could iden- tify the safety topics of certain BTS messages that had humor or pop culture references. In contrast, 85 percent of the subjects could correctly identify the safety topic of BTS messages that did not include humor or a pop cul- ture reference. In addition, subject performance of a secondary control task also degraded significantly when simultaneously viewing BTS messages with humor or pop culture references, especially if the message could not be cor- rectly interpreted by subjects. Other research has found that BTS messages utilizing humor tend to cause increased brain activity when reading the message than do other types of messages (Shealy et al. 2020). Such increased activity implies higher levels of attention and mental effort being expended to read and understand the mes- sage, which could explain why abilities to attend to other tasks while trying to read such messages can become compromised. FHWA also specifies the following to be inappropriate for VMS, even as part of a BTS message: • Website (URL) addresses, domain names, hashtags, or electronic device application names. • Telephone numbers. • Statistics (highway fatalities, citations issued). • Personal safety messages not related to traffic. • Public awareness campaigns not related to traffic. • Public safety alerts (except for Homeland Security and AMBER alerts). • Public service announcements. • Sponsor acknowledgments. • Weather conditions or advisories except as related to expected adverse road-weather conditions. • Full-motion video, flashing symbols, or other graphic features or icons not specifically provided for in the MUTCD. FHWA Rules Regarding BTS Messages on VMS • BTS messages on VMS should supplement a larger roadway safety campaign and be coordinated with enforcement efforts. • They should be tailored to the safety issues experienced on the type of roadway where the message is being displayed. • BTS messages suggested by the public should be revised as needed to meet acceptable VMS message design criteria. • Use of humor, wit, colloquialisms, and pop culture references should be avoided in BTS messages. • Use of websites, domain names, hashtags, or electronic device application names in the message should also be avoided. • Scrolling lines, animation, flashing displays, punctuation, and nonapproved symbols should not be used in BTS messages. Source: Kehrli 2021 Fewer than 50 percent of drivers were able to correctly identify the safety topic of certain BTS messages that had humor or pop culture references.

1-10 Behavioral Trafc Safety Messaging on Variable Message Signs Design Criteria for BTS Messages on VMS Maximum Message Length Given that drivers only have a limited amount of time to read VMS messages, agencies should strive to make messages as short as possible. e MUTCD has issued standards on the design and display of VMS messages (MUTCD 2009). Specically: • All VMS messages, including BTS messages, shall consist of no more than two phases. e collection of words and characters that are displayed together at the same time on VMS con- stitute one VMS phase. • For two-phase messages, each phase shall be understood by itself regardless of the sequence in which it is read. • Messages on VMS shall be centered within each line of legend. With respect to BTS message length for display on VMS, shorter messages are always desirable. Based on recent human factors testing conducted during BTSCRP Project BTS-02, BTS messages for display on VMS should be limited to 16 words or numbers or fewer in total. Furthermore, at locations and time periods that create a high workload environment for the driver, agencies should consider limiting their BTS messages to 11 words or fewer. at same study also found that BTS messages should be limited to a single safety topic. It is acceptable to display a message about a specic safety topic on one phase and a general information statement (travel times, a generic “drive safely” statement, etc.) on a second phase so long as the total length of the message does not exceed 16 words or the number maximum. Start Each New Thought on a New Line Because drivers who are operating their vehicles can only safely take brief glances at messages while approaching the VMS, the message itself must be designed and formatted to assist the driver in quickly processing the information presented. For instance, a BTS message may con- tain multiple thoughts or phrases that naturally go together. Separating the thoughts or phrases on separate lines of the VMS signicantly improves comprehension, as shown in Figure 6 below. e VMS should display no more than three lines per phase. Each Phase Should Be Understood by Itself Similarly, when two-phase messages are used on VMS, a thought or phrase should not be split across the phases. Rather, each phase in a message should be understood on its own and not require information from one phase to understand the other phase. Figure 7 illustrates how WATCH YOUR SPEED NOT YOUR PHONE WATCH YOUR SPEED NOT YOUR PHONE Incorrect Correct YOU TALK YOU TEXT YOU CRASH YOU TALK YOU TEXT YOU CRASH Incorrect Correct Figure 6. Each thought or phrase in a BTS message should start on a new line.

VMS Message Design and Operating Principles for BTS Messages 1-11   improper splitting of thoughts across two phases on VMS makes it more dicult to compre- hend, especially when the driver rst views the sequence of phases reversed from what the mes- sage designer likely intended. BTS messages longer than two phases are not allowed on VMS. Furthermore, as can be seen in the correct example, it is acceptable for a thought or phrase to extend across two or more lines on the VMS (“ . . . OR GET PULLED OVER”). Nonstandard or Texting Abbreviations Should Not Be Used in a BTS Message Although it may be tempting to employ a more conversational style and use cellular phone text message abbreviations in BTS messages, such abbreviations should be avoided if the mes- sage is to be displayed on VMS (see Figure 8). Not all drivers text regularly and so may not know the texting abbreviations. us, the use of such abbreviations may increase confusion and be overly distracting to those motorists. More importantly, VMS are a trac control device and must comply with the standards and guidance in the MUTCD. For this reason, words in the BTS message should either be spelled out correctly or use the acceptable abbreviation listed in the MUTCD, alone or with the appropriate prompt word. If an MUTCD-allowed abbreviation is not available, the message designer should at least vet the proposed abbreviation with others in the oce who are not message design experts to help assess whether the abbreviation will be properly understood by most drivers. Use of Dynamic Features on VMS Because a driver takes brief glances at messages on the VMS while also monitoring road con- ditions and their vehicle, it is important to avoid using techniques that hamper a driver’s ability A DESIGNATED DRIVER DRIVE SOBER OR GET PULLED OVER EVERY PARTY SHOULD ELECT DRINK DRIVE GO TO JAIL Incorrect Correct Figure 7. A BTS message thought or phrase should not be split between VMS phases. DNT TXT & DRV DONT TEXT AND DRIVE Incorrect Correct U DRV U TXT U PAY YOU DRIVE YOU TEXT YOU PAY Incorrect Correct Figure 8. BTS messages on VMS should avoid abbreviations normally used for texting.

1-12 Behavioral Traffic Safety Messaging on Variable Message Signs to perceive messages within a glance. For this reason, the MUTCD prohibits the use of scrolling lines of text or animation on VMS and discourages the use of flashing words or phrases within a message as these techniques have been shown to reduce driver message processing abilities (Dudek 2006). Use of Graphics and Icons VMS technology has advanced significantly in recent years. Many agencies are now procuring high-fidelity VMS that can display high-resolution graphics. High-fidelity VMS can effectively replicate static traffic signs, route shields, and symbols included in the MUTCD. Some agencies have used symbols found in the MUTCD within their BTS message (see Figure 9). It is important to limit the use of graphics within VMS messages (including BTS messages) to those contained within the MUTCD to ensure they are easily perceived and correctly interpreted by motorists. BTS Message Design Checklist for Display on VMS Figure 10 provides a checklist for verifying the appropriateness of a BTS message displayed on VMS. Appendix A provides example BTS message phases (organized by safety topic) that meet this guidance for agencies to consider using for their safety campaigns. CLICK IT OR TICKET REPORT DRUNK DRIVING CALL 911 Figure 9. Graphics used within BTS messages on VMS need to be from the MUTCD. Figure 10. BTS message design checklist for display on VMS.  Supplements an overall traffic safety media campaign coordinated with enforcement efforts.  Addresses a safety issue that is a safety concern for the type of roadway where the message is to be displayed.  Consists of only one or two VMS phases.  Does not split thoughts or phrases in the message across VMS phases. If a two-phase message, each phase can be understood by itself regardless of which phase is read first.  Starts each new thought or phrase in the message on a new line.  Each message line is centered.  Does not include humor, wit, colloquialisms, or pop culture references.  Consists of no more than 16 words or numbers total (in environments where the driver workload is high, limiting the messages to no more than 11 words or numbers is recommended).  Targets only one specific safety behavior. A specific safety behavior on one VMS phase can be combined with general information on a second VMS phase, but the message should not address two different specific safety topics in the same message.  Uses character font and size consistent with agency practices for traffic management messages displayed on the VMS.  Uses abbreviations, symbols, or icons found in the MUTCD or that have been vetted with others to ensure consistent understanding.  Does not use websites, domain names, hashtags, or electronic device application names.  Does not contain scrolling lines, animation, or flashing displays.  Does not use texting abbreviations.

1-13   Most agencies operating VMS have an established VMS policy, use guidelines, or both. Such policies typically state which office or positions within the agency have responsibility for oper- ating the VMS, what types of messages will and will not be displayed on the VMS, the priority assigned to each message type, and other criteria. Most agencies state in their policies that BTS messages are allowable for display on VMS but that such messages are assigned a low priority relative to other VMS messages (traffic operational, regulatory, warning, or guidance messages; Homeland Security or AMBER alert messages; etc.). Agencies with existing VMS policies and guidance should consider enhancing those poli- cies as they pertain to BTS messages. The policy should identify how BTS messages will be developed and what offices or individuals will develop the messages to be displayed. The use of multidisciplinary teams that include individuals with expertise in BTS messaging and VMS mes- sage design principles can be an effective way to generate good messaging ideas while ensuring that the messages themselves are easily read and interpreted by drivers. The policy should state whether only BTS messages about national or state safety campaigns will be displayed on VMS or whether BTS messages on VMS will be allowed during other times of the year as well (around holidays, for example). The policy should also identify how BTS messages will be approved for display on the VMS and who will approve them. Answers to other potential questions regard- ing BTS message design and display could also be addressed in the policy or guidelines. A few examples of such questions are provided below. Will only messages developed for national safety campaigns be displayed, or will other state- and local-level safety initiatives also be supported? Current FHWA guidance indicates that agencies should display BTS messages on VMS pri- marily as a supplement to an overall traffic safety campaign that has strong branding, other media exposure (public service announcements, paid announcements, social media postings) as the primary dissemination mechanism, and is coordinated with enforcement efforts. What BTS message topics will be allowed to be displayed on the VMS? FHWA encourages BTS messages on VMS to address behaviors or safety issues that are likely to be encountered while driving on the facility where the VMS are located. Speeding, tailgating, drunk or drowsy driving, etc. are unsafe driving behaviors that apply to most roadway types (and thus, most VMS locations). Conversely, messages about watching for children or bicyclists or not blocking intersections when traffic is backed up on a facility, are more appropriate for display on VMS along urban arterials rather than on interstates or freeways. Which VMS will be used to display BTS messages? Agencies in rural areas with only a limited inventory of VMS deployed on their roadways may decide to display BTS messages on all of their signs when appropriate. Conversely, agencies in C H A P T E R   4 BTS Message Display Guidelines for VMS

1-14 Behavioral Traffic Safety Messaging on Variable Message Signs large metropolitan areas with extensive VMS infrastructure in their jurisdiction may choose to display BTS messages on a subset of those signs. Some urban agencies also select or develop multiple messages for a single BTS topic and distribute those different versions of the BTS mes- sages among available VMS. In addition, many agencies disseminate travel time information continuously on some of their VMS already and opt to display BTS messages on VMS that are not being used for that purpose. Those agencies that do not have a large number of VMS deployed but which do display travel time information on some signs may choose to display a hybrid message where one phase presents a BTS topic, and the second phase presents travel time information. As stated previ- ously, VMS messages cannot exceed more than two phases total. When and for how long will the BTS messages be displayed on the VMS? BTS messages will typically be assigned a lower priority relative to other traffic management messages, AMBER alert messages, or other Homeland Security messages. Even so, some decisions will need to be made about when BTS messages will be displayed on VMS and for how long. Agencies have considerable flexibility and leeway when making these decisions. For instance, agencies in metropolitan areas generally avoid displaying BTS messages during peak travel periods and only use the VMS for traffic management information. In rural areas, though, it may be con- sidered acceptable to display a BTS message on VMS anytime, day or night, so long as the sign is not needed for a higher-priority message. Metropolitan agencies may opt to display BTS messages for only a few hours per day during off-peak periods on a select number of VMS since most motorists will pass by multiple VMS along their trips. Agencies in rural areas, on the other hand, may choose to leave the BTS displayed 24 hours per day for a few days straight. Finally, most agencies adopt a maximum as to how many safety campaigns and BTS mes- sages they will display on the VMS per month or per year. Doing so allows the agency to better control and manage the use of the VMS in locations where there are frequent requests for BTS messages to be displayed.

1-15   Boyle, L., G. Cordahi, K. Grabenstein, M. Madi, E. Miller, and P. Silberman. 2014. Effectiveness of Safety and Public Service Announcement (PSA) Messages on Dynamic Message Signs. Report No. FHWA-HOP-14-015. FHWA, U.S. Department of Transportation, Washington, DC. Delhomme, P., W. De Dobbeleer, S. Forward, and A. Simões, eds. 2009. Manual for Designing, Implementing, and Evaluating Road Safety Communication Campaigns. Belgian Road Safety Institute, Brussels, Belgium, January 2009. Dudek, C.L. 2006. Dynamic Message Sign Message Design and Display Manual. Report No. FHWA/TX-04/ 0-4023-P3. Texas A&M Transportation Institute, College Station, TX. Guttman, N. 2015. Persuasive Appeals in Road Safety Communication Campaigns: Theoretical Frameworks and Practical Implications from the Analysis of a Decade of Road Safety Campaign Materials. Accident Analysis and Prevention, Volume 84, November 2015, pp. 153–164. Kehrli, M.R. 2021. Uses of and Nonstandard Syntax on Changeable Message Signs. MUTCD-Official Ruling No. 2(09)-174(I). FHWA, U.S. Department of Transportation, Washington, DC, January 4, 2021. Lewis, I., B. Watson, and R. Tay. 2007. Examining the Effectiveness of Physical Threats in Road Safety Advertising: The Role of the Third-Person Effect, Gender, and Age. Transportation Research Part F: Traffic Psychology and Behavior, Volume 10, Issue 1, January 2007, pp. 48–60. Lewis, I., B. Watson, and K.M. White. 2008. An Examination of Message-Relevant Affect in Road Safety Messages: Should Road Safety Advertisements Aim to Make Us Feel Good or Bad? Transportation Research Part F: Traffic Psychology and Behavior, Volume 11, Issue 6, November 2008, pp. 403–417. Mitran, E., D. Cummins, and A. Smithers. 2018. Traffic Safety Messages on Dynamic Message Signs (DMS). Report No. FHWA/LA.18/17-01TA-SA. Louisiana Transportation Research Center, Baton Rouge, LA. MUTCD (Manual on Uniform Traffic Control Devices). 2009. FHWA, U.S. Department of Transportation. NHTSA (National Highway Traffic Safety Administration). n.d. Annual Communications Calendar. https:// www.trafficsafetymarketing.gov/calendars. Rodier, C., R.S. Finson, J. Lidicker, and S.A. Shaheen. 2010. An Evaluation of the Consequences and Effectiveness of Using Highway Changeable Message Signs for Safety Campaigns. Report No. UCF-ITS-PRR-2010-3. Institute of Transportation Studies, University of California-Berkeley, March 2010. Shealy, T., P. Kryschtal, K. Franczek, and B.J. Katz. 2020. Driver Response to Dynamic Message Sign Safety Campaign Messages. Report No. FHWA/VTRC 20-1R16. Virginia Transportation Research Council, Charlottesville, VA. Part 1 References

A-1   A P P E N D I X A Example VMS-Formatted BTS Message Phases by Traffic Safety Topic Cell Phone Use/Texting/Distracted Driving TALK LESS DRIVE MORE NO TEXTING PUT IT DOWN IT CAN WAIT YOU TALK YOU TEXT YOU CRASH DONT TEXT AND DRIVE BE RESPONSIBLE DRIVE NOW TALK OR TEXT LATER DRIVE NOW TEXT LATER IT CAN WAIT ONE TEXT OR CALL COULD WRECK IT ALL DONT TEXT AND DRIVE ARRIVE ALIVE STOP THE TEXTS STOP THE WRECKS NO TEXT IS WORTH A LIFE PUT DOWN THE PHONE JUST DRIVE NO TEXTING PUT IT DOWN ITS THE LAW GIVE DRIVING YOUR FULL ATTENTION READ THE ROAD NOT YOUR PHONE BE SMART SAVE A LIFE DONT TEXT AND DRIVE HEADS UP PHONES DOWN ARRIVE LATE DONT TEXT AND DRIVE YOU DRIVE YOU TEXT YOU PAY STATE LAW NO TEXTING WHILE DRIVING PAY ATTENTION JUST DRIVE BE ALERT YOUR LIFE DEPENDS ON IT DONT BE A DISTRACTED DRIVER BUCKLE UP EYES ON THE ROAD WATCH YOUR SPEED EYES ON ROAD HANDS ON WHEEL MIND ON DRIVING DISTRACTED DRIVING KILLS

A-2 Behavioral Traffic Safety Messaging on Variable Message Signs Seat Belt/Car Seat Use SAFETY HAS NO RIVAL BUCKLE UP BUCKLE UP IN YOUR TRUCK BUCKLE UP IT IS THE LAW BUCKLE UP EVERY TRIP EVERY TIME DO IT FOR YOUR FAMILY BUCKLE UP CRASHES AFFECT EVERYONE BUCKLE UP BUCKLE UP PHONE DOWN BUCKLE UP PHONE DOWN EVERY TRIP CLICK IT OR TICKET CLICK IT OR TICKET ITS THE LAW CLICK IT OR TICKET ENFORCEMENT UP DONT RELY ON LUCK BUCKLE UP BOOSTER SEATS SAVE KIDS CHILD SEAT DO IT FOR THEIR FUTURE BUCKLE KIDS IN CAR SEATS CAR SEATS SAVE KIDS TEACH YOUR KIDS TO BUCKLE UP BUCKLE UP EYES ON THE ROAD WATCH YOUR SPEED BUCKLE UP EVERY RIDER EVERY RIDE PROTECT YOUR KIDS BUCKLE THEM UP SAVE A LIFE EVERYONE WEAR SEATBELTS

Example VMS-Formatted BTS Message Phases by Traffic Safety Topic A-3   Drunk and Drugged Driving DRINK DRIVE GO TO JAIL DRUNK DRIVING KILLS BUZZED DRIVING IS DRUNK DRIVING BUZZED DRIVING IS DRUNK DRIVING DONT CHANCE IT DONT DRINK AND DRIVE ITS STUPID DONT DRINK AND DRIVE ARRIVE ALIVE DRINKING AND DRIVING DONT MIX DONT DRINK AND DRIVE PREVENT A TRAGEDY DONT DRIVE IMPAIRED DRIVE HIGH GET A DUI BUZZED BUSTED BROKE REPORT DRUNK DRIVERS CALL 911 DRIVE SOBER OR GET PULLED OVER DRIVE SOBER OR GET PULLED OVER ENFORCEMENT UP DRIVING SOBER SAVES LIVES BE FREE BE RESPONSIBLE DRIVE SOBER DESIGNATE A SOBER DRIVER WE SALUTE YOU DESIGNATED DRIVERS Drowsy Driving STAY AWAKE STAY ALIVE DONT DRIVE DROWSY ARRIVE ALIVE DRIVING DROWSY IS DANGEROUS DRIVING TIRED IS DRIVING DISTRACTED USE REST AREAS AN ALERT DRIVER CAN AVOID A CRASH DROWSY DRIVING CAN KILL TAKE A BREAK DRIVING DROWSY? REST AREA XX MILES AHEAD STAY ALERT EARLY MORNINGS AND EVENINGS

A-4 Behavioral Traffic Safety Messaging on Variable Message Signs Work Zone Safety/Move Over Law/Move It Law WORK ZONE AWARENESS WEEK GIVE EM A BRAKE USE CAUTION IN WORK ZONES BE WORK ZONE ALERT TAKE TURNS MERGING IN WORK ZONES WORK ZONES… PAY ATTENTION ALL THE TIME EXPECT THE UNEXPECTED IN WORK ZONES PAY ATTENTION SO HIGHWAY WORKERS GO HOME SAFE STAY ALERT IN WORK ZONES ROADWAY WORK PLEASE SLOW DOWN USE CAUTION OBEY WORK ZONE SPEED LIMITS FINES INCREASED IN WORK ZONES SLOW DOWN SLOW DOWN IN A CONE ZONE SLOW DOWN STAY ALERT IN WORK ZONES SLOW DOWN MOVE OVER FOR WORK ZONES MOVE OVER OR SLOW FOR WORKERS ITS THE LAW NO HANDHELD PHONES IN WORK ZONES PROTECT OUR WORKERS SLOW DOWN IN WORK ZONES DONT BARREL THROUGH WORK ZONES WORK ZONES PAY ATTENTION ALL THE TIME WORK ZONE AHEAD STAY ALERT GIVE TRUCKS ROOM FENDER BENDER MOVE VEHICLES FROM TRAVEL LANE STATE LAW MOVE MINOR CRASHES TO THE SHOULDER MOVE OVER SLOW DOWN AT CRASH SCENES MOVE OVER FOR CRASH SCENES MOVE OVER GIVE RESPONDERS ROOM TO WORK MAKE ROOM FOR RESPONDERS MOVE OVER SLOW DOWN MOVE OVER FOR RESPONDERS MOVE OVER FOR RED, BLUE OR AMBER LIGHTS

Example VMS-Formatted BTS Message Phases by Traffic Safety Topic A-5   Speeding/Tailgating/Safe Driving SLOW DOWN AND SAVE A LIFE SLOW DOWN SAVE A LIFE DRIVE SAFELY AT OR UNDER THE SPEED LIMIT SPEED KILLS SLOW DOWN OBEY SPEED LIMIT SLOW DOWN AND OBEY THE POSTED SPEED LIMIT BUCKLE UP EYES ON THE ROAD WATCH YOUR SPEED OBEY THE SPEED LIMIT DONT TAILGATE KEEP SAFE DISTANCE STAY SAFE GIVE YOURSELF ROOM TO BRAKE DONT TAILGATE DRIVE SAFELY ARRIVE ALIVE AVOID AGGRESSIVE DRIVING DRIVE WITH CARE SO WE ALL GET THERE DRIVE SAFELY BE SAFE DRIVE SMART BUCKLE UP PLEASE DRIVE CAREFULLY STATE LAW KEEP RIGHT EXCEPT TO PASS SLOWER TRAFFIC KEEP RIGHT ITS THE LAW KEEP RIGHT LET OTHERS PASS ON LEFT KEEP SAFE DISTANCE STAY SAFE YOU ARE NOT ALONE SHARE THE ROAD SHARE THE ROAD SIGNAL BEFORE CHANGING LANES STAY RIGHT PASS LEFT ITS THE LAW RED MEANS STOP DONT RUN RED LIGHTS

A-6 Behavioral Traffic Safety Messaging on Variable Message Signs Weather Advisories TURN OFF CRUISE DURING WET CONDITIONS BRIDGES ICE BEFORE ROADWAYS USE CAUTION SLOW DOWN USE CAUTION INCLEMENT WEATHER SLOW DOWN DURING WET CONDITIONS WET ROADWAYS PLEASE SLOW DOWN USE CAUTION HEADLIGHTS ON WHEN RAINING ITS THE LAW TURN LIGHTS ON WHEN WIPERS ON HEAD LIGHTS ON WHEN SNOWING DONT CROWD THE PLOW KEEP BACK 300 FEET WATCH FOR SLOW MOVING SNOW PLOWS DRIVING IN RAIN LIGHTS ON FLASHERS OFF ICE AND SNOW COVERED ROADWAYS REDUCE SPEED SLOW DOWN DURING WET CONDITIONS HEAD LIGHTS ON WHEN SNOWING ICE AND SNOW TAKE IT SLOW USE CAUTION ICY CONDITIONS POSSIBLE USE CAUTION Motorcycle/Bicycle/Pedestrian Safety LOOK TWICE FOR MOTORCYCLES RIDE RESPONSIBLY WATCH FOR MOTORCYCLES SHARE THE ROAD LOOK TWICE FOR MOTORCYCLISTS SHARE THE ROAD WITH MOTORCYCLES BLIND SPOTS HIDE MOTORCYCLES ALWAYS LOOK TWICE SHARE THE ROAD WATCH FOR MOTORCYCLES LOOK TWICE FOR MOTORCYCLES LOOK TWICE FOR BICYCLES BIKE SEASON SHARE ROAD GIVE SPACE GIVE BIKES ROOM TO RIDE ALWAYS WATCH FOR PEDESTRIANS WATCH FOR BIKES AND WALKERS