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Publication Number: FHWA-HRT-09-039
Date: April 2010
Pavement Marking Demonstration Project: State of Alaska and State of Tennessee-Report to Congress
Chapter 4. State Bidding and Procurement Processes
The procurement of pavement markings is often a source of conflicting demands placed on agencies. Procurement is not only the simple definition of the purchase of the materials; rather, the term refers to a more holistic view of a contracting mechanism that provides for the purchase and application of pavement marking materials at locations determined by a contracting agency.
As with any contract, the following basic question is asked: How does an agency ensure that it is getting what it has paid for? Typically, this is done by establishing a standard or specification that the contractor must meet. Herein lies the crux of the problem for procuring pavement markings.
While much of the information used to establish the basic standards and specifications are based on previous research and basic scientific principles, there has been an explosion of radically different types of products for pavement marking applications. This growth in product base has outstripped the capability of the research community to adequately and scientifically establish a rigorous basis for what type of pavement marking works best for different applications and locations. While a recent report proposes recommended minimum pavement marking retroreflectivity levels, it does not provide agencies with information on which materials will meet those minimum levels for a given period of time on a specific roadway under typical traffic conditions.(35)
Most State agencies have developed their own standards or specifications to adequately identify pavement marking materials for their specific applications, needs, and regions. Given the vast differences in applications across the country, significant weather differences, differences in vehicle and user populations, and a host of additional factors, the specifications that users have established may be significantly different. In fact, several different types of specifications now exist, including the recipe or component specification, the performance-based specification, and the warranty specification. Complicating the situation even more is that these specifications and the overall performance characteristics change based on the type of pavement marking material (paint, thermoplastic, preformed tapes, etc.).
The following is a root question pertaining to these differing specifications: What are the advantages and disadvantages of any given type? Most importantly, is there evidence to assess the fundamental quality of the pavement markings as a function of the specification used to obtain them? If so, scientific research could be focused on creating a pavement marking specification with potential national applicability which would ensure the desired quality. This in turn could provide better roadway information for drivers, potentially decrease crashes, and save money.
In the recipe or component specification, the specification defines the materials and application parameters for the components of the pavement marking system. Markings are installed by the contractor using marking materials that meet the specification using procedures defined in the specification. This includes parameters such as the type of paint, the size and amount of retroreflective beads per mile of roadway, the immersion depth of the beads, the temperature of the paint and road, and the ambient weather conditions. The specification can get detailed, which can be a significant advantage because agencies know exactly what they are paying for because the provisions of the materials and placements are all tightly defined.
In direct contrast to the recipe specification, a performance-based specification does not define the specifics of the materials and their placement; rather, it defines the overall goal that must be met by the markings. This goal, which typically seeks a minimum level of retroreflectivity within a prescribed number of days of placement, aims to establish a sufficiently high peak or starting point of the pavement marking material. While the performance is known to degrade over time, establishing a performance peak at the beginning essentially assumes a normal “wear and tear” cycle over the anticipated life of the material. This assumption results in the anticipation that the minimum level of the performance indicator (such as retroreflectivity) will coincide with the physical end-of-life cycle of the material, leading to the material being replaced at exactly the right time. An advantage of this type of specification is that it requires less manpower from the agency to inspect markings at the time of application. However, not enough is known about the marking performance over time in different locations and applications to accurately set initial performance metrics to produce repeatable end-of-life cycles.
The warranty specification is essentially a type of performance specification. However, instead of focusing on an initial metric, the specification focuses on what the performance metric (typically retroreflectivity) should be at the end of the life cycle of the marking. This life cycle may vary greatly depending on the application and type of material. Some warranty specifications are up to 5 years long. If the metric is not met at the end of the service life, the contractor must replace the marking under warranty. The use of this procurement method has obvious implications on contracting timeframes, lengths of contracts, payment schedules, inspection procedures, and other similar items.
Surveys on State Bidding and Procurement Processes
As stated previously, the following is a fundamental question: What are the advantages or disadvantages of any given specification mechanism? Additionally, do these advantages provide the capability to assess the quality of the markings procured under any type of specification? Given that the scientific evidence to answer these questions is lacking, most of the available information comes from surveys or workshops.
A 2007 survey performed for the Iowa Department of Transportation (Iowa DOT) Pavement Marking Task Force investigated the use of performance-based specifications across other State transportation departments.(36) Of the 23 responses received, 13 indicated the use of some type of performance-based specification, most typically requiring a minimum initial retroreflectivity. The responses were varied in terms of what types of materials were procured by a performance specification. A number of responses indicated a mix of specification types where paint used a recipe specification but more advanced types of markings such as thermoplastics and tape utilized a performance characteristic. In most cases, the performance metric was initial retroreflectivity. Of the 23 responses, only 5 responses, or 22 percent, used a performance specification across all marking types.
There were no additional follow-up questions relating to the specification type, quality assessments, or any information pertaining to actual or perceived quality of the markings obtained by the different specification mechanisms. Therefore, the only real observation that can be drawn is that while performance specifications are in use in some respect in roughly 50 percent of the States, their wholesale application to all material types is much smaller. Many States are still using the recipe specification, especially for paint, which is the most common pavement marking material.
The National Cooperative Highway Research Program Project 39-13, “Pavement Marking Warranty Specifications,” focused on a national survey on State experiences with warranty specifications in 2008. The research team took advantage of this opportunity to request the addition of several questions that were specifically related to the effect of State bidding and procurement processes on the quality of pavement marking material. While the survey had a number of questions, the first question (shown in Figure 9) was directly comparable to the 2007 Iowa DOT survey described above.
Figure 9. Chart. 2008 survey question—procurement process.
Figure 10 shows the graph of the responses for the first question in the 2008 survey. A total of 29 responses were received from agencies, which included State transportation departments and Canadian provinces. While it is evident that the majority of the respondents are still using a recipe specification for the procurement of most types of pavement marking materials, a closer look at the data reveals some interesting facts. In many cases, agencies reported the use of more than one type of specification. For example, for the procurement of paint markings, 6 of the 29 respondents indicated the use of both recipe- and performance-based specifications. Four respondents indicated that they used overlap for thermoplastics, four respondents indicated that they used multicomposite, and seven indicated that they used preformed tapes. These results demonstrate that agencies are not limiting themselves to a single procurement mechanism for a specific marking material. It may also show that agencies are using composite specifications such as a recipe specification with some performance requirements (e.g., initial retroreflectivity). Because these results were somewhat unexpected, there is insufficient detail in the later questions to explore this issue in more depth.
Figure 10. Graph. 2008 survey response—type of specification versus material.
A comparison of the responses by agencies that participated in both the 2007 and 2008 surveys is also interesting. There were 12 agencies that responded to both surveys. Of these, seven reported the same results in both surveys. One agency that reported the use of performance-based specifications in 2008 did not report that same use in 2007. Four agencies which had reported the use of performance-based specifications in 2007 did not indicate the use of such specifications in 2008. However, the second question of the 2008 survey (shown in Figure 11) which addressed the issue of changes in the specification type used to procure pavement markings, indicates that agencies did not actually revert back to a recipe specification after using a performance specification. Therefore, differences in responses between 2007 and 2008 may be due to differences in how the questions were asked and how the answers were tabulated.
Fourteen respondents answered “yes” to the question in Figure 11, while 15 respondents answered “no.” There was no timeframe mentioned with regard to the change in specification, so there were no direct comparisions available to the 2007 survey. The list of responses from the 15 agencies stating “no” includes the following:
“We have implemented a performance-based spec for temporary markings in one of our regions. All permanent markings and temporary markings in the other regions use recipe/ component specifications. Performance specifications have not been implemented due to funding issues for conducting the retroreflectivity testing.”
“Neither performance-based nor warranty-based specifications are used because we do not want to keep contracts open when monitoring pavement marking performance. In-house application only.”
“We are considering changing to performance-based but haven’t had time to pursue it yet.”
“Always relied on performance evaluations.”
“Performance-based specifications seem to be of greater benefit in more northern climates where the striping cycle is shorter and subject to more harsh conditions. To date, we have not identified a definite benefit of performance-based contracts. Also, we may not have sufficient manpower to correctly monitor the condition of markings over a lengthy contract.”
“We supply the product (paint and glass bead) which we procure using a component specification. Placement by private contractors is performance-based (most placement is done by our own department forces). We work with paint suppliers to develop the specification for the materials and this collaborative approach is working well. As a result, there are no plans to change the process.”
“We have better control with the recipe. We tried one warranty but it was painful. The supplier eventually honored the warranty, but it was like pulling teeth.”
“We have had success with this type of specification.”
“We only approve pavement markings that are placed on our NTPEP (National Transportation Product Evaluation Program) Test Deck.”
Questions 3–6 of the 2008 survey focused on ascertaining the reasons for the change as well as any benefits or consequences.
Question 3 listed several common reasons for changing from a recipe to a performance-based specification and asked respondents to identify all those reasons which were applicable (see Figure 12).
Many agencies responded with more than one reason, so the total number of responses represented in Figure 13 is significantly greater than the number of agencies (14) that indicated a switch in their specifications.
Figure 13. Graph. 2008 survey response—reasons for switching to performance-based specification.
The four most common answers were the following:
The lack of State forces for inspection is a significant answer because it points to a particular onus or disadvantage of the recipe specification. In a recipe specification, because individual components are detailed, a significant amount of checking or inspection may be required to assess if the contractor is applying the materials in accordance with the specification. By comparison, in a performance-based specification, the inspection needs are typically reduced since a reduced number of performance indicators such as retroreflectivity are inspected.
The answer for a lack of quality or durability indicates that a significant number of the respondents are trying to increase the quality of their pavement markings and are using performance-based specifications as one avenue to achieve that goal.
Question 4 of the 2008 survey asked respondents to identify the benefits of the move to a performance- or warranty-based specification (see Figure 14). Although the format of the question provided no mechanism to differentiate between expected and realized benefits, respondents were asked to check all the answers that applied. Because of this, the tally of the number of responses to the individual items in question 4 is larger than the number of respondents answering “yes” to question 2.
Figure 15 shows that the highest number of responses were associated with a desire to lower the life-cycle costs and obtain more durable markings. This indicates that agencies use or are at least investigate the use of performance- or warranty-based specifications to improve the quality of the pavement markings.
Figure 15. Graph. 2008 survey response—benefits of switching to a performance-based or warranty-based specification.
Question 5 of the 2008 survey investigated whether there were any unintended circumstances of the switch in specification type (see Figure 16). Respondents were once again asked to check all the answers that applied. Because of this, the tally of the number of responses to the individual items in question 5 was larger than the number of respondents, indicating a switch in their specifications.
Figure 16. Chart. 2008 survey question—unintended consequences.
Figure 17 shows a fairly even distribution across all the responses. The expectation therefore is that a switch to a performance- or warranty-based specification should hold no hidden trouble spots.
Figure 17. Graph. 2008 survey response—unintended consequences of switching to a performance-based or warranty-based specification.
The final question in the 2008 survey was an open-ended question asking respondents to describe how the change in specification in use has affected the quality of the markings. The following responses were received:
There is no research that conclusively demonstrates that a move to performance- or warranty-based specifications for the procurement of pavement markings will result in higher quality installations. In fact, as evidenced by reviewing recent surveys of State agencies, there is a wide disparity in how agencies are procuring pavement markings. This is perhaps influenced by the lack of a national standard for basic pavement marking performance, such as retroreflectivity.
The surveys cited in this report show some important trends and information. First, many States are implementing or at least experimenting with performance- or warranty-based specifications. It is reasonable to assume that in a time of significant fiscal constraints, this trend represents an underlying belief that the pavement marking procurement process can be improved by moving to a different type of specification. Furthermore, responses from the surveys indicate that many of the agencies investigating these types of specifications are doing so to obtain higher quality, longer life cycles, increased durability, and a reduction in administrative costs such as inspections.
The scope of these responses goes beyond one or two agencies and is largely similar across different surveys performed at different times. Not only does this provide some degree of verification to each survey effort, but it also indicates a widespread national interest in improving the quality of pavement markings. The procurement process is certainly one area that appears reasonable to have an impact on that quality by moving to a mechanism that prescribes expected results regardless of the makeup of the materials.
The effort that State and local agencies expend on the installation and maintenance of pavement markings, as indicated through the surveys and the direct and supportive participation in the demonstration projects, indicates that these agencies are exercising due diligence in meeting their fiduciary responsibilities for providing a critical public service at the lowest possible cost.
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Topics: research, safety, roadside, pavement marking
Keywords: research, safety, Acrylic waterborne paint, Durability, Environmental impacts, Pavement markings, Retroreflectivity, State bidding procedures, Wider edge lines
TRT Terms: research, Safety and security, Safety, Transportation safety