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30 chapter seven Conclusions The objective of this synthesis study was to provide examples life method and agencies can utilize sign information for plan- of effective and advantageous practices that illustrate how ning, scheduling, and budgeting. Simplicity and ease were the different types of agencies can meet the Manual on Uniform most valued benefits in the blanket replacement method. It is Traffic Control Devices (MUTCD) retroreflectivity require- an effective practice to evenly and consistently blanket replace ments. The aim of this study was to document the state of the signs within an agency from year to year. Purchasing a retro- practice and identify content that could assist other agencies reflectometer can be expensive; however, such measurements exploring different methods for maintaining sign retroreflec- could be valuable, particularly in support of other methods. It tivity. Information was obtained from past research, exist- is an effective practice to utilize the control signs method to ing guidance and policy, and telephone surveys. The surveys justify the extension of sign warranty periods so that agencies comprised the majority of the information in this report. The can expand sign service life and maximize potential resources. survey questionnaire included 14 main questions and was Lastly, replacing signs based solely on retroreflectivity mea- designed to facilitate an open-ended conversation about sign surements can be time-consuming. If an agency has access to a retroreflectivity and general maintenance practices. retroreflectometer, it is most beneficial when used in conjunc- tion with routine daily maintenance; however, the readings Surveys were conducted with participants from different should not detract or eclipse other important activities. parts of the country. Overall, 48 agencies participated and 40 operate roadways open to the public that selected a sign This synthesis study revealed that survey participants were retroreflectivity method from the MUTCD. From participant implementing a variety of primary and secondary methods for responses it was determined that the expected sign life method maintaining signs and ensuring retroreflectivity compliance. was the most selected primary and secondary method for Selection ranking aside, participant responses showed that replacing and managing signs. The second most frequently each method exhibited distinct advantages and operational reported was visual nighttime inspection; however, agen- benefits. cies were somewhat conflicted about this method. Survey participants were typically separated into two groups; agen- It should also be pointed out that FHWA has a report detail- cies that have used nighttime inspection and agencies that ing each of the sign retroreflectivity methods listed in the do not. The primary reason for rejecting nighttime inspec- MUTCD. The FHWA report also includes a useful descrip- tion was that agencies were concerned about staffing and did tion of how to conduct the assessment methods. Finally, it not want to add another activity to an already demanding also outlines the advantages and disadvantages of each of maintenance schedule. The blanket replacement method was the sign retroreflectivity methods listed in the MUTCD, and the third most selected method and agencies employing this can be found at: http://safety.fhwa.dot.gov/roadway_dept/ approach praised it for its ease and straightforward applica- night_visib/policy_guide/fhwahrt08026/. tion. Finally, a few agencies were implementing the mea- sured retroreflectivity or control signs methods. The cost for One final note, FHWA has started rule making that may a retroreflectometer and time requirements for the measure- potentially change the MUTCD language regarding sign retro ments were the deciding factors. reflectivity (see Federal Register, Vol. 76, Volume 169, pp. 5415654162). A final rule has not yet been issued and is The survey findings identified several strategies and tech- not expected to be issued until the summer of 2012 (after the niques that were considered as effective practices. The effec- current J anuary 2012 compliance date to select and imple- tive practices are described in chapter five and varied for each ment a sign retroreflectivity maintenance method). Although MUTCD method. The most noteworthy practice for the visual these on-going rule-making activities may change the spe- nighttime inspection was the implementation of training pro- cifics of the minimum retroreflectivity regulations in the grams to ensure inspector proficiency. Resource management MUTCD, it is still considered good practice to maintain sign tools were the most prominent benefit for the expected sign retroreflectivity for nighttime drivers.