Practices to Manage Traffic Sign Retroreflectivity (2012)

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14 This chapter summarizes the general material from survey responses and includes valuable practices, trends, and guid- ance. The first section covers the survey results, and the follow- ing sections are comprised of noteworthy information for each of the five different assessment and management methods. Survey reSultS The survey participants were identified from agency web- sites, past presentation materials, and referrals and contacted through professional society e-mail lists, meeting announce- ments, and professional contacts. In some cases, they noti- fied the consultants that they were interested in participating; in other cases, it was the consultants who requested participa- tion. Most of the surveys were conducted by telephone and typically lasted 30 minutes. A few participants forwarded written survey responses or detailed e-mails owing to time constraints. In total, this study received responses from 49 different agencies and organizations. Figure 3 contains a map of the survey participants and a list of the different agencies can be found in Appendix C. The survey included a broad sample and the participants came from all time zones in the contiguous 48 states. Geo- graphic and climatic conditions were diverse. The local agencies were located in different demographic areas from both urban and rural conditions, with population densities ranging from 30 to approximately 3,800 residents per square mile. Agency sign inventories ranged from fewer than 4,000 to an estimated 1.3 million. Survey participants came from 24 local agencies, 16 state DOTs, and 8 others. Local agency respondents were from 2 towns, 7 cities, 14 counties, and 1 toll road agency. The others category included survey par- ticipants that did not manage public roads and were not in a position to implement a MUTCD method for maintaining sign retroreflectivity, and consisted of LTAP centers, private consultants, and a product vendor. Table 3 contains the distribution of the 40 agencies that have selected a method for replacing and maintaining a sign population. For clarification, the total survey participant count was 48; however, the agencies that operated roadways open to the public numbered 40. The difference was a result of the “other” category. The table shows the five MUTCD methods and the number of agencies that have selected it as a primary and secondary method. The primary method was defined as the agency’s principal approach for identifying and replacing signs. The secondary or support methods were strategies that supplemented the primary method and helped to ensure sign compliance. Each agency is represented in the primary method column, but this was not always the case for secondary meth- ods. Some agencies did not employ a secondary method and others combined two or three. For example, one agency used visual nighttime inspection as the primary means for identify- ing inadequate signs; however, it also had a sign inventory system to better manage resources and collected control sign measurements to monitor sheeting material longevity. viSual Nighttime iNSpectioN The visual nighttime inspection method was the second most selected method. Thirteen agencies employed this as their primary method and two agencies used it as a secondary or support method. Despite its common use, it was deter- mined that most of these agencies could be divided into two distinct groups: agencies that have implemented nighttime inspection in the past and agencies that quickly rejected it. A few agencies selected the method when they had no pre- vious inspection experience; however, the majority of the participants were could be placed in the two distinct groups. In addition, it was noted that many agencies believed that they were in compliance with the MUTCD because they were routinely inspecting their signs at night. However, during the interviews it was discovered that they were not actually fol- lowing the three procedures FHWA has outlined for night- time visual inspections. Those agencies that did not use nighttime visual inspec- tion were most concerned with the potential of increased tort lawsuits because of the subjectivity of this method. Two agencies in urban areas were dissuaded from using visual nighttime inspection because sign inspector safety could not be guaranteed in certain high crime areas. However, the most common concerns regarding nighttime inspection regarded staffing, overtime pay, and schedule modification. Some of the survey agencies were downsizing and it would have been difficult to expand maintenance activities with existing limi- tations. Generally, the rejection group believed that visual inspection required too much time and resources. All survey participants with visual nighttime experience gave it positive remarks. With regard to staff demands and chapter three raNge of practiceS

15 scheduling, the agencies noted that there were challenges, but none were insurmountable. The scheduling of nighttime inspection sessions differed among agencies; some in the north conducted inspection sessions in either early fall or late spring, whereas others in the south preferred the win- ter months. The common key is conducting sign inspec- tions during the time of the year when there is less daylight. Nighttime inspections were also typically scheduled when there were less frequent maintenance activities. In rural areas, a night session would last approximately 3 to 5 hours and cover about 100 miles of one direction of a roadway. Inspectors would stop if dew or frost started to form on the signs. Most agencies employed a team of two that consisted of a dedicated driver and a sign inspector; however, there were some agencies that completed inspections with just one employee, but it was not common. Visual sign inspection was usually documented on a specialized form or a notepad, whereas some agencies used audio recording devices. A few survey participants elected to complete all of the nighttime inspection sessions during a period of one or two weeks, whereas others completed them over several months when there were periods of downtime. One agency preferred to use all of the maintenance staff and a few office person- nel to complete all roadway inspections in one night. This way the inspections are quickly out of the way and the main- tenance staff can move on to other items. One agency has multiple sign crews; when one sign crew conducts nighttime inspections, the other sign crews compensate by assum- ing a larger share of the routine daytime sign maintenance. Most agencies have their maintenance staff adjust their work schedules to complete inspections within an 8-hour shift. Map Key: Local Agencies Other Agencies FIGURE 3 Map of survey participant locations. Note: The gray shading indicates the participating state DOTs. The “Local Agencies” (•) include towns, cities, counties, and a toll road agency. The “Other Agencies” (D) include LTAPs, private businesses, and other survey participants that did not select a MUTCD method. MUTC D A ssessment and Management Methods Primary Sign Replacement Method Secondary or Support Method Local Agencies* State DOT s Local Agencies State DOT s Nighttime Inspection 6 M easured Retroreflectivity 2 0 0 0 Expected Sign Life 1 1 4 1 1 Blanket Replacemen t 3 5 4 0 C ontrol Signs 2 2 0 7 5 5 5 0 *The local agencies include towns, cities, counties, and the one toll road agency. The sum of the Primary Sign Replacement Method columns adds up to 40. The Secondary or Support Method columns add to a different total because it is not required to have a secondary method and agencies may have multiple support methods. TAbLE 3 DISTrIbuTION OF METHOD SELECTION

16 There may be overtime or shift differential pay for some of the inspections; however, it was not queried in the survey. Another important aspect of this method concerns the inspection intervals or frequencies. The MUTCD does not state how frequently signs should be inspected, whether once per year or once every two years. There were several agencies that consistently inspected all roadway signs each year; however, inspection intervals ranged from four per year to once every five years. The agency with a five-year interval was conserva- tive with inspections and more likely to remove any question- able signs. One respondent expressed the opinion that when the inspection interval was longer, there was a higher possibility of having inadequate signs on the roadway. Conducting nighttime inspections once per year appears reasonable, but this study did not identify any optimal inspection interval. Visual nighttime inspection can also be used as a second- ary or temporary support method. One agency needed to con- duct a quick assessment of the overall sign population and utilized nighttime inspection to sample various roadways in the county to better understand the quality of the existing signs for a cost analysis. The nighttime inspection of sam- pled roadways revealed that approximately one-third of the signs were inadequate. Consequently, the agency elected to implement an expected sign life method in an attempt to save adequate signs as opposed to wasting resources in a county- wide blanket replacement. One of the benefits of visual nighttime inspection cited most often was maximizing sign service life. One participant mentioned that Type III signs between 10 and 15 years old would typically look fine during inspections. One DOT noted that this method can extend the use of some signs for up to 20 years. The MUTCD does state that “the retroreflectivity of an existing sign is assessed by a trained sign inspector” (1). Some of the DOTs had established training programs that consisted of field demonstrations and/or instructional mate- rials. One DOT placed signs of various retroreflectivity lev- els along a local racetrack and maintenance personnel were trained to find the substandard signs. Another DOT had a computer-based training course that provided examples and descriptions of failed signs and an inspector would complete a short test that was kept on record. It was mentioned that certain LTAP centers also provided training courses, but the majority of the participants relied on past experience and on- the-job training. It was common to hear that many inspectors had between 10 to 20 years of job experience. For additional resources on visual nighttime inspection, the MUTCD refers readers to 2007 FHWA publication Main- taining Traffic Sign Retroreflectivity (FHWA-SA-07-020) (14). In that publication, FHWA recommends that an agency use one or more supportive techniques for nighttime visual assessments, including consistent parameters, calibration signs, and comparison panels. Apart from training, most agencies had not decided which supportive technique(s) they plan to implement. Several of the DOTs were exploring cali- bration signs, but have not formalized procedures. One DOT was using a retroreflectometer to measure signs that were recently replaced to find signs that were at or near the mini- mum levels to be used in the calibration procedures. There was one sign sheeting manufacturer that began producing comparison panels; however, there were no respondents that were aware of the manufacturer’s product before the surveys were conducted. There was some confusion with the sup- portive technique requirements and this was one area where participants thought more guidance would be helpful. meaSured retroreflectivity Measured retroreflectivity was the least selected method and most agencies did not consider it as a primary method for maintaining minimum sign retroreflectivity. The LTAP cen- ters surveyed strongly recommended other methods because of the high cost for a retroreflectometer and for the considerable demand on labor and time. Again, there were two different types of retroreflectometers and each cost approximately $10,000 to $12,000 per unit. Most agencies are currently trying to do more with less and the purchase of a retroreflectometer was not a cost-effective option. Along with the initial cost, measuring a large sign population can be a substantial drain on manpower. Some of the surveyed DOTs possessed a retro reflectometer and used it for periodic sampling; a few local agencies also own a retroreflectometer and several had the ability to borrow a unit from an LTAP center. The Minnesota DOT’s Traffic Sign Maintenance/ Management Handbook (22) states that data collectors following the ASTM E1709-00e1 standard can measure approximately 20 signs per hour, although a lower rate of 10 to 15 unwashed signs per hour was documented in a 2011 Trb publication (23). In this study, the data collection pro- cess measured between 80 and 120 signs per day. The higher rate was only achieved once and was the result of continuous favorable shoulder conditions and signs that were spaced close together. Measurements take time and can be a tiring process if readings are collected over prolonged periods of multiple hours. The measurement rate is also heavily dependent on the roadway conditions and the location of the sign. based on past data collection experience, some measure- ments may be difficult and time-consuming to obtain as a result of physical barriers, sign height, and shoulder conditions. Some retroreflectivity measurements may require that technicians use a ladder or a truck with a boom lift. bridges, guardrails, unstable roadway shoulders, limited sight distance, overhead mast arms, and nearby railroad tracks are just a few examples of difficult measurement conditions. High-speed and high- volume road- ways may also place sign technicians in undesirable locations where it would be prudent to have additional traffic control. There are ample opportunities to measure signs on a roadway for a control sign sample or study; however, some sign mea- surements may not be worth the time and effort.

17 In the survey, two agencies were exploring the use of the measured retroreflectivity method as their primary approach for replacing signs. The first agency was a county with a population of approximately 114,000 residents in mostly rural areas. The engineer estimated that there are approxi- mately 80,000 signs on 2,600 centerline-miles. The county attorney was concerned about tort liability and believed that measured retroreflectivity would be the best method to ver- ify sign compliance. The sign measurements would also be recorded and tracked in a sign inventory system. The county engineer would like to purchase several retroreflectometers for maintenance staff. The agency already inspects each sign and sign support once per year during daytime hours. The engineer envisioned that the maintenance staff would collect and record retroreflectivity measurements as they perform their yearly inspections. Signs would be replaced primarily when the readings were near or below the minimum levels to extend sign use. This participant reported that the method was still being developed. Overall, the county planned on combining existing maintenance activities with an additional step to ensure sign compliance and maximize service life. The other agency using the measured retroreflectivity method was a toll road organization that operates a prominent bridge, multiple transit facilities, and approximately six miles of roadway. The participant estimated that they currently manage about 400 signs. The agency used Type III sheeting and wanted to maximize the service life of existing signs. A few years before, a student intern created a basic sign inven- tory system in Excel; however, the sign information had not been kept up to date. The initial plan was to borrow a retro- reflectometer from the local LTAP center for up to two weeks. A team of maintenance technicians would collect retroreflec- tivity readings for all signs. They would also have a chance to update and verify information in the existing sign inventory system. The measurements would help to prioritize immedi- ate sign replacements and the updated information would be used when establishing an expected sign life system where future replacements are based on service life periods. expected SigN life Of all the sign retroreflectivity maintenance methods listed in the MUTCD, the expected sign life method was found to be used the most often. Several of the LTAP centers rec- ommended that agencies strongly consider some type of expected sign life system to better manage resources and track sign data. When asked if they had any advice to provide to other agencies, the most common response from partici- pants was “know how many signs you have on the roadway.” Although this method is based on individual sign replace- ments, the practical implementation is centered on effective management and organization of sign data. With the pend- ing compliance dates on sign retroreflectivity, it appears that agencies finally have the justification to build a sign inven- tory, assess the signs’ condition (specifically retroreflectivity but other characteristics as well, such as hardware, place- ment, and necessity) of the sheeting, and predict the remain- ing life using expected sign life. Among the survey participants, 17 of 41 agencies uti- lized this method as their primary means for replacing signs. Of the participants that selected alternative sign methods, 16 of the 24 agencies implemented some type assessment method system as a secondary method. regardless of being a primary or secondary method, there were many common aspects between both approaches. For this section, primary and secondary methods that manage and track sign informa- tion were broadly referred to as an expected sign life system. There were two basic ways that the expected sign life method was used. One way was to build an inventory, assess the signs’ condition (especially retroreflectivity), and then develop an estimate for the remaining number of years that the signs could be in service. The second way to implement the expected sign life method without building an inventory is to start installing date stickers on the signs. regardless, agencies still need to have an estimate of their signs’ service life. Some agencies used the manufacturer’s warranty periods as a default service life and replacement period. A manufacturer’s warranty period guarantees that a sign will retain 80% of the original retroreflectivity levels over a certain time period and does not represent a sign’s ser- vice life. A sheeting material can last significantly longer than the warranty period. One city used a replacement period of 7 years for Type I sheeting. Others reported that their service life replacement periods were based on past experience and field observations. A few participants conducted formal stud- ies to justify the extension of the previous replacement period with the purpose of maximizing resources. A Midwestern DOT’s formal study extended the replacement period from 14 to 18 years for Type III signs and they hope to achieve 20 years of service life for signs on overhead sign panels (24). Service life replacement periods varied substantially; how- ever, 10, 12, and 15 years were common. Some of the litera- ture relevant to sign life was included earlier in this report. Apart from service life, most survey respondents acknowl- edged that they were able to identify sign age from the date stickers that were placed on the backs of signs. The stickers by themselves had little effect on maintenance; however, it was generally agreed that this was a good practice. beyond the installation of date stickers, an agency needs some type of structured and systematic approach for manag- ing information and replacing signs such as in a sign inventory system. One basic method would be maintaining a collection of photographs that depict roadway signs and document the installation date. An additional step would be to maintain a formal written list of sign information; however, when deal- ing with large quantities of constantly evolving sign data, it is better to have a more robust system. Sign inventories are described further later in this report.

18 BlaNket replacemeNt blanket replacement was the third most selected method by survey participants. Seven agencies use this method as their primary means for sign replacement and two agencies use it as a secondary approach. Agencies that employed blanket replacement often described it as simple and easy to imple- ment, although this method did have its detractors. The most common concern was the potential waste of labor and materials that came from replacing adequate signs. A research report in 2006 examined past NCDOT sign bud- gets and determined that the agency replaced 4.7% of the sign population as a result of vandalism or damage (13). One of the DOT participants tracked and monitored sign activities throughout the state and estimated that for any given year 10% of all signs were knockdowns. Another agency tracked the installation of 3,000 signs from 1995 and found that approximately one-third remained on the roadway 16 years after installation. These examples illustrate that many signs will not last to the end of the blanket replacement cycles and there will always be replacements resulting from routine attrition. regardless, many survey participants have been able to successfully address the waste issue. Agencies using the blanket replacement method curtailed sign waste by setting certain sign tolerance periods and try- ing to reuse adequate signs. For example, one of the surveyed DOTs implemented a corridor blanket replacement method with a replacement cycle of 15 years. That DOT has gathered empirical data and collected regional sign measurements to determine that certain sheeting materials can last up to 15 years and sometimes longer. During corridor replace- ments, it would salvage and not remove any sign in the road- way that was less than three years old. Most signs in that state were replaced after 15 years; however, some could have a maximum installation age of 18 years. In this instance, the blanket replacement cycle and tolerance period were based on the DOT’s experience and a certain level of comfort. Another DOT implemented a different approach to reduc- ing waste and salvaging adequate signs. This DOT set the blanket replacement cycle for roadway corridors at the 10-year warranty period. The participant acknowledged that most signs would be adequate after the warranty period, but they did not have a formal study to verify that the replace- ment cycle could be systematically extended. In the absence of such a study, the DOT utilized the visual nighttime inspec- tion as a secondary method to extend sign longevity and to ensure retroreflectivity compliance. basically, the DOT set the blanket replacement cycle at 10 years, but would not replace any sign that had been installed for six years or less. With the combined methods, the maximum installation of a sign was 16 years, and the nighttime inspection helped to extend the use of a sign in lieu of a formal study. On a smaller scale, a participant from a midsize county salvaged signs during blanket replacement, which would be removed from the roadway and used as backups or in reserve. based on the county’s experience, signs would typi- cally last between 10 and 15 years. The county resurfaces or reconstructs certain roadways each year and during that time all signs on the resurfaced roadways would be replaced. One advantage to this approach of combining roadway resurfac- ing and sign replacement was that the funding would come from the construction budget as opposed to the mainte- nance budget. In certain cases, there may be more funding and flexibility when dealing with the construction budget. To reduce waste, the county borrowed a retroreflectometer from the state LTAP center and measured signs that they per- ceived to be salvageable. The salvageable signs were stored at the maintenance office and used as backup or in reserve. For example, if a STOP sign was knocked down during the weekend, a maintenance technician would use one of the sal- vaged signs as a quick and adequate replacement. One county selected the blanket replacement method because sign replacement could be easily documented. The survey participant was concerned about liability and a pos- sible increase in tort lawsuits. The county attorney believed that blanket replacement was the easiest method to document and defend in court. For this agency, waste and removing adequate signs from the roadway were not major issues. Its approach was to divide the county into different regions and sign replacements were staggered for a 10-year cycle, which was based on the warranty period. When a region was sched- uled for replacement, all of the signs were removed regardless of installation age and nothing was salvaged. The county kept records of work orders and sign replacements to verify that all signs were under warranty and within compliance. The agency acknowledged that signs could last longer than the warranty periods; however, it was more important to the agency to reduce liability than try to extend sign service life. coNtrol SigNS The control signs method was another approach that few agen- cies considered and only two agencies selected it as a primary means of replacing signs. One of the agencies was actively implementing the method and the other was in the preliminary phases of determining formal procedures. Many participants did not thoroughly investigate this method because it requires both a retroreflectometer for collecting measurements and a system for managing sign data. This method may take time to implement but it does have advantages. The agency implementing the control sign method estab- lished it in 2007 and maintains approximately 32,000 signs. The county owned a retroreflectometer and had setup a sign inventory system that was developed in-house to manage and track individual signs. Each year, maintenance technicians measured the retroreflectivity of 150 of the oldest signs for each sign color. These signs are in the field and are unpro- tected. The sign inventory system was utilized to determine the locations of the oldest signs on the roadway. The oldest

19 signs served as the control sample and it was believed that if these signs were still meeting the minimum levels, then the newer signs should also be adequate. The estimated time requirement for a team to complete all measurements was approximately 40 hours. The yearly retroreflective readings were analyzed to identify sign failures and failing contrast ratios. The new readings were compiled with the past mea- surements to determine retroreflective deterioration rates for different sheeting types. In theory, control sign failures would identify the regional service life periods and all signs with a similar installation age would be targeted for replace- ment. The county started using Type III sheeting in 1995 and switched to Type IV a few years ago. Sixteen years after installation, there had not been any measurements that were below the MUTCD minimum levels; therefore, there had not been any targeted replacements. The county was pleased with the control signs method and has presented material on the strategy in several conferences and meetings. The agency plans to continue the same control signs procedures and they have expressed interest in purchas- ing a second retroreflectometer. As stated earlier, this was the only agency implementing control signs as the primary sign replacement method; however, there are several that have used a similar strategy as a secondary or support method. Of the surveyed DOTs, 6 of the 16 state agencies pos- sessed retroreflectometers. In 2007, one state completed a sign service life study. This DOT collected retroreflectivity and chromaticity measurements from 211 Type III control signs in the field. The control signs were located in two dif- ferent parts of the state, and the sample varied in color and type. The results helped the agency to justify the extension of the blanket replacement cycle from 14 to 18 years. The control sign measurements also determined that some of the red STOP signs failed to meet some of the color require- ments in ASTM Standard D4956-09. The agency believed it had been being too conservative with blanket replacements and the control sign measurements helped it to ascertain a more appropriate cycle length. In 2009, that DOT officially changed sign sheeting from Type III to Type IV and planned on continuing control sign measurements to establish a suit- able cycle length for the new sheeting. Another DOT using this method set up a control signs test deck to establish regional service life periods for exist- ing sheeting materials and to evaluate new products as they are introduced into the market. The control signs test deck consisted of 56 signs that varied in color and material type. It was located in a protected maintenance yard office in the state capital. The DOT positioned the signs to face south and tilted them at a 45 degree angle to accelerate the deteriora- tion process. retroreflectivity measurements were collected every six months and readings were compiled to analyze sign deterioration rates. The control signs test deck helped to establish an appropriate service life period for the DOT’s expected sign life method. In a different approach, one county planned to utilize con- trol sign measurements to monitor failed signs and evaluate visual nighttime inspectors. The county arranged to borrow a retroreflectometer from the state LTAP center with the pur- pose of collecting measurements of failed signs that were removed and replaced. The participant stated that the read- ings could help to identify if signs with high retroreflectivity levels were being removed prematurely or if sign inspectors needed to remove certain signs sooner. In this case, the con- trol signs method was not only used to monitor sign retro- reflectivity, but it was also implemented to help reevaluate and improve existing maintenance practices. SigN iNveNtorieS The new minimum sign retroreflectivity standards in the MUTCD do not require agencies to build and/or maintain sign inventories. However, it was evident that many of the agencies contacted during this study believed that the new minimum sign retroreflectivity standards gave them the final justification they needed to build a sign inventory so that they could best manage their signs. Sign inventories varied in functionality and complexity, but many were relatively simple and developed in-house. One of the simplest computer-based systems was developed by a student intern as a summer project for one of the sur- veyed agencies. The intern formatted an Excel spreadsheet to include the desired sign attributes and it was found to work well for a sign population of fewer than 1,000. Another participant also used Excel and it worked satisfactorily for a much larger sign population. In a similar approach, one agency created an Access database that interfaced with ArcView to manage both sign and spatial data. That sys- tem was developed in 2001 by in-house staff and the system included attributes, pictures, and GPS coordinates for more than 10,000 signs. One of the DOTs was operating a system that was developed in the 1980s by agency staff from a DOS program. The system was a somewhat cumbersome and the participant needed replacement; however, it still served a valuable purpose. Another county used an in-house system for tracking sign replacements and work orders that started as paper records. An employee took the paper record format and expanded it into a computer-based program. The program started with modest origins; however, it had evolved to include pull-down menus, advanced data filters, and mapping capabilities. Nonprofit agencies and private businesses offer a wide range of software packages and products to manage sign inventories. In the nonprofit category, systems have been created by LTAP centers or university-based organizations. These programs are sometimes free or can be purchased at a reasonable cost. Two examples include Transportation Asset Management Software from the utah LTAP center and road- soft from the Center for Technology & Training at Michigan

20 Tech university. Two of the surveyed agencies used one of the programs and both expressed positive opinions. Survey participants also used a variety of commercially available off- the-shelf systems, several of which were spoken of highly. Essentially, the key was selecting a system that fits an agen- cy’s requirements, which was easier said than done. One participant acknowledged that finding existing soft- ware packages was not difficult; however, it was determining which one best accommodates an agency’s needs and desires that was. Another survey participant was evaluating differ- ent programs at the time of this report and was preparing to solicit vendors to present the system to the agency. Expected sign life systems are long-term strategies, but a large part of that investment comes at the beginning during the initial sign data collection process. Each agency has created its initial sign inventory and gathered the data differently. One DOT in the north started the process during the winter when there was downtime. The staff reviewed roadway video-logging files and aerial images at the beginning of the initial data collection. In the spring, staff traveled the roadways to gather additional data and to confirm the accuracy of the initial collection. One surveyed county collected sign data and GPS coordinates for approxi- mately 24,000 signs during the summer. A team of one full- time employee and one student intern absorbed the data collection tasks in with their regular summer maintenance activities. The county engineer described the data collection process as manageable and indicated that the student intern was a significant help in the creation of the sign inventory. A surveyed private consultant shared his experience with inventorying sign data for nine u.S. military installations. One of the challenges for the consultant was estimating time demands and he determined that a team of two could collect data for 220 signs each day. The consultant advised that an agency should determine what sign attribute information is needed before starting the collection process. He also recom- mended that it was easier to gather inessential sign data in the initial collection than in a secondary effort. One partici- pant acknowledged that the data collection process helped to identify where additional signs were needed and where unnecessary signs could be removed. In addition to traffic signs, many of the participants inven- toried and incorporated other roadway items into the same system. For example, one of the LTAP software packages included modules to manage signs, culverts, guardrails, and roadway pavement conditions. Participants mentioned that they also include pavement striping, roadway no-passing zones, and sidewalk data into the same system. One agency started with a program that was originally purchased to man- age bridge information. Once the staff gained proficiency with administrating bridge data, the system was expanded to man- age other roadway items such as signs and culverts. Another participant recognized that it was more important to imple- ment one system that can encompass multiple roadway items than to have multiple systems that manage one asset each. One of the advantages to sign inventory is the ability to quickly access sign data. One participant reported that its sys- tem was frequently used when there was an inquiry from a concerned resident. Staff could promptly access specific sign information and promptly address the issue. Another exam- ple involved missing signs; a technician in the field would report any missing signs to the main office. The office would directly identify the missing sign and process the work order. In this way, the field technician would not be required to spend much time investigating and the replacement process could be accelerated. The last example deals with knockdown signs. before cre- ating a sign inventory, one agency made two separate trips to handle such incidents. The first trip would ascertain the sign type, dimensions, and necessary hardware and the sec- ond trip was for the actual replacement or repair of the sign. Having a sign inventory eliminates the first trip, because a technician can determine all of the sign information from an office computer. Quickly accessing sign information is valu- able and particularly beneficial when time is an issue. Agencies have also been incorporating new technologies into their sign inventories with the goal of streamlining main- tenance. Several of the surveyed DOTs were in the process of transitioning their current systems to web-based platforms. uploading large quantities of sign data has been time- consuming and a new platform can significantly reduce the data processing time. One large city was expediting activi- ties by implementing a paperless maintenance system; work orders would be received and completed digitally. Another agency was implementing a similar strategy, but with tab- let computers that maintenance technicians could use in the field. It is possible that in the future maintenance staff will be able to receive work orders, query sign information, and upload GPS coordinates with smartphones or other similar devices from the side of the road. Of all the advantages of the sign inventory, most of the agencies touted the planning and management capabilities. Participants consistently noted the benefits of knowing the number of signs on the roadway for future planning, schedul- ing work orders, tracking replacements, and budgeting yearly sign expenses. One DOT was able to budget sign replace- ments three years in advance, allowing them to address any funding concerns with DOT administrators. When switching from Type III to Type IV sheeting, one participant was able to quickly prioritize and budget Type III sign replacements. A city utilized sign data to estimate the cost of bringing its sign inventory into compliance for the 2015 and 2018 dead- lines. Similarly, a DOT was able to predict that the mini- mum retroreflectivity requirements would cost an additional $2.5 million per year to meet the 2015 deadline. In both cases, the agencies were better able to seek additional fund-

21 ing sources because they provided detailed information and were able to express a clear need. Despite the potential advantages of a sign inventory, a system is only useful if the sign information is accurate. One individual remarked that the most difficult task of sign management activities was keeping the sign inventory up-to- date. Another DOT transitioning to a new and more advanced system, reported a gap in time when sign information and replacements could not be updated. This period of inactiv- ity resulted in some difficulties for maintenance staff and impeded the initial progress of the new system. Along with keeping the sign information current, it was also critical to keep staff proficient and trained. One of the participants shared experiences with a new program and initial training. It was acknowledged that many of the maintenance technicians have limited experienced with computer programs. Many had concerns about the new system and believed that maintenance practices were fine without adding further responsibilities. The solution was to quickly create a support group that could address the techni- cian’s initial concerns. The support group also gathered tech- nician feedback to help customize the program and make it more user-friendly. The agency brought in a vendor to pro- vide training and initial technical support. The technicians were able to gain a sense of ownership for the system when they were involved from the onset of the project. The partici- pant indicated that the sign inventory system was now a large part of the technicians’ routine tasks and there have not been any major concerns. based on the responses from this effort, it is clear that there are many advantages of developing and using a sign inventory system that go beyond simply managing sign retroreflectivity. Most agencies use their systems for the potential planning and resource management capabilities. One participant stressed that it took a great deal of time and troubleshooting before benefits could be achieved, and that other agencies considering this method should stay commit- ted, exercise patience, and continue to make incremental improvements.