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7 TABLE 1 TALLY OF SURVEY RESPONSES No. of No. Providing Population Responses Warranty Agency Category Surveyed (response rate) Specifications U.S. State Departments of Transportation 50 40 13 (80%) Canadian Provincial and Territorial 13 8 2 Transportation Organizations (62%) Total for All Agencies Surveyed 63 48 15 (76%) erage of many details of warranty requirements and pavement marking warranties. In addition to these analytic administration. results, the survey yielded considerable supplementary infor- Agencies that have discontinued their use of pave- mation through managers' responses to open-ended questions. ment marking warranties. Three of the 48 respond- This additional information supplied reasons for particular ing agencies (6%) reported that they had used pave- responses to questions, pointed out directions toward which ment marking warranties, but have since discontinued the agency's warranty program is now evolving, discussed their use. factors (such as climate and materials quality control) that Agencies that do not use and have no plans for affect pavement marking performance and ways in which future use of pavement marking warranties. Twelve warranties account for those influences, and suggested needs of the 48 responding agencies (25%) do not now use for future research. This supplementary information is likewise pavement marking warranties and are unlikely to revise discussed in chapter three. their position in the foreseeable future. Agencies that have not used pavement marking WARRANTY NOMENCLATURE warranties but are potentially interested. Ten of the AND PERFORMANCE TIMELINE 48 responding agencies (21%) do not now use pave- ment marking warranties, but are willing to consider A nationally recognized quality assurance glossary presents future use. the following definition: Warranty specifications. A type of performance specification The statistical findings of the survey that are presented in that guarantees the integrity of a product and assigns responsibility chapter three are based primarily on the responses from the for the repair or replacement of defects to the contractor (Source: 23 U.S. and Canadian agencies that reported current use of Glossary of Highway . . . May 2005). Do Not Use Pavement Marking Warranties But Are Potentially Interested 21% Currently Use Pavement Marking Warranties 48% Do Not Use & Have No Plans For Pavement Marking Warranties 25% Have Used Pavement Marking Warranties But Discontinued Use 6% FIGURE 1 Breakdown of survey respondents.

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8 (a) Warranty Period Measured from Date of Application / Installation Initial Acceptance (b) Warranty Period Measured from Date of Acceptance (Not to Scale) Inspection After Typically 6 Months to 6 Years Application FIGURE 2 Typical pavement marking warranty timeline. Under this umbrella, two types of warranty specifications application require correction, this repair must be com- are further defined: pleted before the markings will be accepted. The time allowed for such repair is specified in the construction Materials and workmanship warranties. Specifications that hold the contractor responsible for correcting defects in work documents and is considered part of the "initial accep- elements within the contractor's control during the warranty tance" period in Figure 2. period. [Under materials and workmanship warranties [for pave- Figure 2 illustrates two options in how a pavement ments], the highway agency is responsible for the pavement marking warranty period is described in specifications. structural design. The contractor assumes no responsibility for pavement design or those distresses that result from shortcom- Option (a) shows the warranty period measured from ings in the design. Some responsibility is shifted from the agency marking installation or application. Option (b) shows to the contractor for materials selection and workmanship.] the warranty period commencing after the pavement markings are initially accepted. Because the time between Performance warranties. Specifications that hold the contrac- tor fully responsible for product performance during the war- installation/application and inspection/acceptance can ranty period. [Under performance warranties [for pavements], be relatively short (e.g., 30 days or less), the practical the contractor guarantees that the pavement will perform at a difference in the durations of these two options is gen- desirable quality level. The contractor assumes some level of erally negligible, particularly for multi-year warranties. responsibility, depending on the specific project, for the struc- tural pavement or decisions on the mix.] The duration of current U.S. and Canadian pavement marking warranties varies from 180 days (6 months) to (Source: Glossary of Highway . . . May 2005. Note: The outer 6 years (72 months), based on information reported by set of [square brackets] in each definition above is part of the surveyed agencies. published definition. The inner set of square brackets [for pave- ments] has been inserted by the author to clarify that the defini- tions presume the application of these warranties to pavement Warranties in force for less than 1 year may be used by projects.) agencies that manage roads in harsh climates or that use short-lifetime products such as paint. These warranty periods Although these definitions could be adapted from "pave- are structured intentionally to encompass a single winter ment warranties" to "pavement marking warranties," later season. Figure 3 illustrates this subset of the general case findings will show that a more refined explanation of war- described earlier. ranty timeline and nomenclature will be useful. It will help in understanding how agencies actually implement warranty The initial acceptance period in Figure 3 includes inspec- specifications with respect to various periods of performance tions to verify that pavement markings conform to construc- monitoring. Figures 2 through 5 illustrate several options currently in use. Together they illustrate different ways of structuring pavement marking warranties and establish a Initial Warranty Period consistent nomenclature for use in later chapters. Acceptance (IL: "Performance Period") Figure 2 presents the typical sequence of events conducted (Not to Scale) by most of the 23 agencies that reported using pavement marking warranties. Post-Application Inspection; Specs May Example: 180 Days Through One Also Impose Calendar Winter After application or installation the pavement mark- Dates ings are inspected to determine that they conform to Note: IL = Illinois DOT. project construction specifications, in which case they are accepted by the agency in the "initial acceptance" FIGURE 3 Pavement marking warranty timeline through one period shown in Figure 2. If deficiencies in the initial winter period.

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9 Observation Period Warranty Period (Not to Scale) Typically 180 Days Typically 1 to 6 Years FIGURE 4 Pavement marking warranty timeline involving an observation period. tion specifications, as discussed for Figure 2. However, the tance period or the performance or observation periods actual start of the warranty period may also be affected by must be corrected before moving to the next performance calendar dates imposed by contract. For example, specifica- monitoring stage. tions may call for the warranty period to start on the later of Following successful completion of the performance or two dates--the date of initial acceptance or a particular date observation period, the warranty period begins, typi- specified in the contract (usually in October or November). cally extending for 1 to 6 years of additional time. For This method ensures that the warranty period (i.e., 180 days those surveyed states that use an observation period, the in Figure 3) carries through the entire winter season. Although warranty is provided by the manufacturer of a durable one agency refers to the second period in Figure 3 as a "per- pavement marking product. formance period," this report will use the label "warranty period." This practice follows the more widespread usage Figures 2 through 5 reinforce that state and provincial agen- among other agencies that apply the warranty concept of Fig- cies evaluate pavement marking performance in a number of ure 3, and reserves the term "performance period" for another ways through different contractually defined periods. For interpretation that is explained here. purposes of this study, the definition of a "pavement marking warranty period" has been based on the following consider- Some agencies use other configurations of pavement ations: (1) how individual agencies have characterized their marking warranties: own pavement marking performance periods in their specifi- cations and survey responses; (2) a consensus among sur- Following application, there is an "observation period" veyed agencies that a warranty of performance follows, and in which the pavement markings are observed in ser- is distinct from, meeting construction specification require- vice for a specified length of time; for example, 180 days ments during marking application/installation; and (3) a con- (6 months). This observation period may itself be the sensus among surveyed agencies that successful conclusion basis for initial acceptance, followed by a longer war- of a warranty period relieves the contractor and/or materials ranty period. This approach is used by Maryland State manufacturer of further responsibility for pavement marking Highway Administration (SHA), Nebraska, and South performance. To recap the nomenclature that will be used in Carolina for their durable pavement markings (Figure 4). this report: Alternately, initial acceptance may be followed by an additional "performance period," the approach used by Initial acceptance: the determination of whether pave- Texas for its RPMs and Delaware for its retroreflec- ment markings meet project construction specifications tive preformed patterned tape. The performance for initial performance. An inspection to make this deter- period is followed by a longer warranty period, as mination typically occurs within a short time following shown in Figure 5. application (e.g., 30 days or less), but pavement marking Deficiencies in meeting construction specification initial acceptance may occur, for example, up to 180 days requirements that are observed during the initial accep- after application if an observation period is used. Initial Accept- Performance Period Warranty Period ance (Not to Scale) 60 Days Inspection (TxDOT RPMs) or 1 Year (TxDOT RPMs) or After 1 Year 4 Years (DelDOT Tape) Application (DelDOT Tape) FIGURE 5 Pavement marking warranty timeline involving a performance period. TxDOT = Texas Department of Transportation; RPMs = raised pavement markers; DelDOT = Delaware DOT.