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

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15 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. scheduling, the agencies noted that there were challenges, was usually documented on a specialized form or a notepad, but none were insurmountable. The scheduling of nighttime whereas some agencies used audio recording devices. inspection sessions differed among agencies; some in the north conducted inspection sessions in either early fall or A few survey participants elected to complete all of the late spring, whereas others in the south preferred the win- nighttime inspection sessions during a period of one or two ter months. The common key is conducting sign inspec- weeks, whereas others completed them over several months tions during the time of the year when there is less daylight. when there were periods of downtime. One agency preferred Nighttime inspections were also typically scheduled when to use all of the maintenance staff and a few office person- there were less frequent maintenance activities. In rural nel to complete all roadway inspections in one night. This areas, a night session would last approximately 3 to 5 hours way the inspections are quickly out of the way and the main- and cover about 100 miles of one direction of a roadway. tenance staff can move on to other items. One agency has Inspectors would stop if dew or frost started to form on the multiple sign crews; when one sign crew conducts nighttime signs. Most agencies employed a team of two that consisted inspections, the other sign crews compensate by assum- of a dedicated driver and a sign inspector; however, there ing a larger share of the routine daytime sign maintenance. were some agencies that completed inspections with just one Most agencies have their maintenance staff adjust their work employee, but it was not common. Visual sign inspection schedules to complete inspections within an 8-hour shift. Table 3 Distribution of Method Selection Primary Sign Replacement Method Secondary or Support Method MUTCD Assessment and Local Local Management Methods Agencies* State DOTs Agencies State DOTs Nighttime Inspection 6 7 0 2 Measured Retroreflectivity 2 0 0 0 Expected Sign Life 11 4 11 5 Blanket Replacement 3 5 4 0 Control Signs 2 0 5 5 *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.