Nighttime Visibility of Traffic Signs: Appendix C - Summary of 1995 Workshops

[GH25] 

The following summary was prepared by the contractor (BMI) that developed and facilitated the 1995 workshops on minimum levels of sign retroreflectivity.

COMMENTS/FEEDBACK FROM WORKSHOP PARTICIPANTS

By Hugh W. McGee^[7]

BACKGROUND

Under a requirement of the 1991 ISTEA legislation, the Federal Highway Administration (FHWA) was charged to develop a standard for minimum maintained levels of sign retroreflectivity (R_A) for traffic signs. These minimum levels would be considered thresholds, below which the sign would be considered inadequate for meeting driver visibility and legibility requirements, and therefore should be replaced. FHWA has developed preliminary minimum values for four types of signs, which were presented in "Minimum Retroreflectivity Requirements for Traffic Signs."  Also, BMI, under it's contract with FHWA, has prepared a preliminary draft of "Guidelines for Implementation of Minimum Retroreflectivity Requirements for Traffic Signs." The purpose of that document was to offer guidelines to State and local jurisdictions on how each could cost-effectively insure that their signs meet these minimum retroreflectivity requirements. As part of the contract, BMI with the assistance of FHWA, conducted a workshop in three cities for the purpose of receiving comments from State and local jurisdictions on the preliminary minimum R_A values and the information and recommendations presented in the Guide. This document presents the comments that were received and discusses how these comments may affect the guidelines presented in the draft guide.

The three workshops took place at the following locations and dates:

• Hanover, Maryland - October 23 and 24, 1995
• Denver, Colorado - November 8 and 9, 1995
• Kansas City, Missouri - November 27 and 28, 1995.

The number of participants, who were mostly from State or local jurisdictions, for each workshop was limited to about 15. Appendix A provides the agenda which was followed for each workshop (with minor variations for timing) and Appendix B provides the list of participants. [Ed. note: these appendices are not provided in this report.]

SUMMARY OF COMMENTS

In general, similar comments were received from all three workshop participants. Therefore, the comments made by the participants will be reported collectively. It should be noted that unless otherwise mentioned no distinction is made as to how many of the participants may have made the same comment.

Minimum Retroreflectivity Requirements and Values

The following comments were expressed by the participants regarding the need for minimum R_A values and the values that have been initially suggested from FHWA research:

1. Some voiced concern that FHWA has not adequately established that there is a safety problem resulting from signs with poor levels of retroreflectivity. More precisely, a relationship between sign retroreflectivity condition and the occurrence of accidents has not been adequately established. Agencies will need to be convinced that inadequate sign retroreflectivity degrades safety to such an extent that it is worth spending (transferring) more funds on a sign management system (inventory/inspection/replacement) vis-à-vis other problems.
2. There are significant differences between State and local jurisdictions as to their resources (funds, staff, expertise) available for insuring that signs are kept above the minimum value. Very small jurisdictions are not capable of carrying out a "sign management" program and therefore, there is likely to be non-compliance among these jurisdictions. Many considered this to be an unfunded mandate.
3. The research to date has not been convincing for supporting the R_A values. There is a degree of arbitrariness to the values, which will make it difficult for widespread acceptance of the values even as a guideline.
4. There was nearly unanimity that the values should not be issued as a standard. Suggested alternative "terms" were:
   • Guidelines
   • Desired Values
   • Optional Program
   • Advisory Program
   • Goals to Achieve
   These "terms" would apply to the actual R_A values as well as to the Sign Management System elements, i.e., inventories, inspections, etc.
5. There was confusion and misunderstanding, and may still be for some, as to why for two groups of sign types (i.e., black/yellow and black/white) increasingly higher R_A for brighter materials are required. (Jeff Paniati went to considerable length to explain the reason for this at the workshops, which resolved the concern for most.) This misunderstanding likely will persist despite attempts at clear explanations in the "Guidelines for Implementation of Minimum Retroreflectivity Requirements" or any other document that includes minimum values.
6. There was a limited amount of criticism of the R_A values, per se. In general those from the States, thought they seemed about right while those from local jurisdictions thought some were too high. (Any criticism of the values from a substantially subjective viewpoint should not be taken too seriously, Agency personnel will need to view signs with inadequate R_A values in on-road conditions before they pass any judgment on the minimum R_A values. The informal night time rating demonstration was not conclusive [nor could it be given its non-experiment approach], but it did show that most participants were in agreement in rating very low R_Asigns as inadequate.)
7. Only the red values were questioned as possible being too high. However, a few noted that for some values, the minimum value for Type I (Engineering Grade) signs was too close to the value for new material, a situation which may result in agencies no longer purchasing that grade material. Many agencies cannot afford the higher priced high intensity sheeting.
8. The minimum values for the most frequently used signs (e.g., speed limit signs) should be re-evaluated since they would require the most funds to replace.
9. Consider not requiring minimum values for local roads because the users know the road and would not require the same retroreflectivity level as unfamiliar drivers. For the very low volume local roads, "unfamiliar" drivers are rare. (This opinion was not accepted by all.)

Implementation Considerations

1. Several suggestions were made regarding the application of the R_A requirements. These included:
   • Establish a sign priority program whereby certain signs are considered more critical and should meet the minimum values. The obvious critical signs were STOP, YIELD, and DO NOT ENTER and possibly warning signs.
   • Limit the R_A Requirements to signs on certain roads:
     • a) National Highway System
     • b) Functional Class
       • - Primary - YES
       • - Secondary - MAYBE
       • - Local - NO REQUIREMENT
     • c) Classes of roads by other criteria
       • - Type (design)
       • - Speed
       • - Volume
       • - Rural vs. Non-Rural
2. As to the timing for conformance to the minimum requirements, suggestions were:
   • Normal Sign Replacement - When the sign is replaced for whatever reason, then it must meet the minimum R_A requirements. (Not a practical approach because an agency may allow an existing sign to degrade well below the minimum value to avoid it being subject to the requirement. Also, there is no practical way to monitor this policy.)
   • The minimum R_A would not take affect until a specified year in the future. A 3 to 5 year schedule with preference for the 5-year horizon was suggested.
3. FHWA should establish categorical funding for implementation of minimum R_A.
4. FHWA should recognize that there are a lot of very small jurisdictions with no staff, or their staff has no or limited knowledge of signing principles, and have little or no money budget for signing. In this regard, it was recognized that small jurisdictions will need to seek the assistance of larger jurisdictions or the state LTAP (Local Transportation Assistance Program).

GENERAL COMMENTS

1. To "sell" this requirement, it would help to:
   • a) Describe the benefits
   • b) Describe what, if any, increase in budgets would be necessary.
2. With regard to the suggestion that all jurisdictions should have an inventory, the following should be considered:
   • a) The number of states and local jurisdictions with a sign inventory is still relatively small.
   • b) Most local jurisdictions do not have the funds to develop an inventory.
3. There was considerable concern over the terminology used for rating signs that are at or below the minimum values. Most agreed that the terms "inadequate" and "unacceptable" were not the best terms to use. Some also felt that "minimum" should not be used in connection with the R_A values. One suggestion was "less than desirable".
   It was suggested that legal staff should review these terminology issues and offer appropriate guidance. Whatever terms are used they should provide latitude.
4. With regard to sign inspections, comments made were:
   • Despite the suggestion in the Guide that all signs do not have to be inspected for R_A each year, some agencies will feel compelled to inspect all signs (at least those requiring minimum R_A) because of tort liability protection.
   • Sign inspections should focus on a visual inspection. Measuring sign R_Ais costly and impractical. Also, it was suggested that a visual reference chart, similar to that developed by Nevada DOT, be prepared to assist in visual inspection.
   • If signs are to be measured, provide guidance on how (i.e., number and location of measurements), frequency, etc.