Practices to Manage Traffic Sign Retroreflectivity (2012)

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27 The effective practices identified by this study are presented here. They are presented as general sign practices and then for each sign retroreflectivity maintenance method. In addi- tion, Appendix D contains common questions, myths, and answers associated with the new minimum sign retroreflec- tivity standards in the MUTCD. General SiGn PracticeS • Type I sheeting material can still be used in certain situ- ations; however, it is more cost-effective to install Type III or Type IV as a minimum standard. • Explore sheeting materials and products that have a long service life. The higher cost of materials may be offset by reduced labor and fewer sign replacements. • Stress the importance of sign assessment to staff dur- ing routine daily maintenance. It is also important to monitor such issues as sheeting color, vandalism, and damaged sign posts. • Keep yearly sign maintenance and management practices consistent. Routine schedules and operations help to set a basic level of quality and prevent periods of neglect. • Prioritize current and future sign replacement if resources are limited. Create a list of priorities and address items on the list in descending order such as targeting STOP and regulatory signs first, replacing warning signs, and so on. • Unnecessary signs may be a substantial drain on agency resources and are not to be installed for political rea- sons. During sign inspections, assess whether each sign is still needed. • Continue to seek maintenance information from out- side sources such as FHWA, LTAP centers, surround- ing agencies, conferences, workshops, journal articles, professional societies, etc. • Identify sign assessment and management strategies that your agency could implement in a practical and efficient manner. • Create a comprehensive sign plan that addresses exist- ing and long-term goals. • Document your sign assessment and management strat- egies and be able to demonstrate that you are actively implementing your approach in a consistent manner. • Consider providing routine training for employees who deal with sign management and maintenance activities. • Continue to reexamine your approach and long-term goals. Methods and strategies can be modified to improve operations and to better manage resources. ViSual niGhttime inSPection • FHWA intends for agencies to use one or more of the sign inspection procedures documented in Maintain- ing Traffic Sign Retroreflectivity (FHWA-SA-07-020) (14). If none of these procedures are used, an agency must be able to justify the deviation with an engineer- ing study. • For the calibration signs technique, commercial grade or Type I signs could be used. Signs removed from the roadway with known retroreflectivity levels at or slightly above the MUTCD minimums could also be used. • It is more effective for inspections to be completed with a team of two, if possible, and during favorable weather conditions. • It is best to perform nighttime inspections when there is flexibility or downtime in a staff’s schedules. Inspec- tions must not detract from daily activities and ideally the method would supplement and support routine maintenance. • Inspection intervals or frequencies depend on an agen- cy’s capabilities and resources. • Provide written expectations and guidelines for inspec- tors to follow. Handout materials can document the agen- cy’s procedures and offer descriptions and examples of adequate and failed signs. • Implement training for both new and experienced sign inspectors. Agencies may create their own pro- grams or participate in courses that are provided by the LTAP center or the state DOT. Having done visual nighttime inspections does not necessarily equate to training. • Require a visual nighttime inspection form that an agency can utilize to document the sign inspection process. The forms can document such information as the roadway, inspector, date, and signs identified for replacement. • Inspection teams monitor and report any other mainte- nance issues that are observed during nighttime inspec- tions. The primary focus is on signs; however, the team might also be able to observe pavement markings, delin- eators, and other retroreflective items. • Quality assurance checks can help to improve the inspec- tion process and provide feedback to sign inspectors. Such checks can be completed with a retroreflectometer or by another impartial sign inspector. chapter five effectiVe PracticeS

28 meaSured retroreflectiVity • Measurements should follow ASTM Standard E1709 with four or more readings per sign color. • The measured retroreflectivity method is best suited for agencies with smaller sign populations. • It is important that collecting readings be completed within a manageable timeframe. The measurement process need not consume excessive amounts of time that could result in other maintenance activities being neglected. • Measurements are to be combined with other routine maintenance activities. For example, staff can collect readings when examining sign supports or when repair- ing knockdown signs. exPected SiGn life • Resources for service life values for sign sheeting materi- als are available from FHWA, sign manufacturers, LTAP centers, DOTs, nearby agencies, and research reports. • Expected sign life systems can be used to extend sign service life, expedite maintenance operations, and help manage resources. • When selecting or developing a system, agencies should consider both existing and future needs and necessities. • Systems should be able to expand and evolve over time. An agency must also be aware that systems may become obsolete or experience technical difficulties. There needs to be contingency plans for salvaging important data or transitioning to a new system. • It is best to gather a wide range of sign data in the initial collection process to avoid having to collect additional information in a secondary effort. • During the data collection process, it is beneficial to re- examine signs on the roadway to identify where addi- tional signs are needed, where changes need to be made to comply with the MUTCD, and where unnecessary signs could be removed. • It may be desirable to use the same or a similar system for multiple roadway items such as culverts, guardrails, road- way pavement, striping, no-passing zones, and sidewalks. • Agencies need to be committed to the long-term use and support of this method. The system is only valuable if the data are kept up-to-date and accurate. Blanket rePlacement • Replacement cycles need to be regular and staggered evenly from year to year to help with planning, schedul- ing, and budgeting. • Agencies need to document blanket replacement details such as cycle length, procedures, and segmented road- ways/areas. • Salvaging or reusing adequate signs could be consid- ered if resources are limited. • Records and work orders could be used to demonstrate that signs are replaced within a reasonable and accept- able time period. control SiGnS • Temporarily borrowing or renting a retroreflectometer might be considered if purchasing a unit is not feasible. • Agencies should be able to justify their control signs’ sampling procedures. It is important to establish an acceptable number of control signs and set appropriate measurement intervals. • It is important that measurement data be accumulated and analyzed throughout the years to identify trends in sheeting performance and sign deterioration. • Control sign data could be used to establish regional service life periods for certain sheeting materials. The regional data could then be used to extend service life for signs in the blanket replacement or expected sign life methods.