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6 developed to gain their input on how well the procedure is being used in signing and marking curves. It may well be would work and the likelihood that those responsible for plac- that routine decisions are made by technicians with engineers ing curve signs will comply. becoming involved only when atypical or more difficult sit- uations are encountered. However it is still the non-engineer who is defining such situations. PRACTITIONER SURVEY The MUTCD is the most widely used guideline because most respondents claimed that it (or a similar state version) To obtain a broader view, a nationwide survey of practi- was used in their jurisdiction. The ball-bank indicator is tioners responsible for specifying and implementing TCD the most common device for determining advisory speeds treatments for horizontal curves was undertaken. Consistent although many respondents use road geometry or test-drives with other project tasks, the emphasis was on rural two-way, in addition to or instead of the ball-bank indicator. Many two-lane roads. An estimated total of 1,250 practitioners from respondents indicated that much of the training for sign spec- state, county, and city agencies in all 50 states were sent a ification is done "in-house." While standards and guidelines 20-question survey by mail or e-mail; 344 responded. Those are accepted, they are not always followed. In-house and who received the survey were asked to respond and forward other forms of peer-to-peer training can lead to consistency it to as many people as they deemed qualified to answer the over the years within a jurisdiction, but not necessarily questions. For this reason, an exact response rate cannot be among jurisdictions. This inconsistency among jurisdictions determined. However, based on the 1,250 that were sent out, can also be seen in the low level of response to questions 344 responses would represent a response rate of 25%. Of asked about practices in other jurisdictions and in the fact the 344 practitioners that responded, 177 (52%) were from that respondents thought that practice such as setting advi- state agencies, 144 (42%) from county agencies, and 20 (6%) sory speeds was done less consistently in "other" jurisdic- from city agencies. City officials were not targeted for re- tions relative to their own. Respondents also often answered sponses because of the project's rural-road focus. In states "I don't know" or left these questions blank, which also where the state DOT has jurisdiction over all roads within the implies a potential lack of sharing of best practice among state, county responses were not available. The largest num- jurisdictions. ber of responses (37, 11% of the sample) came from Michigan Curves within the respondents' jurisdictions were reported counties, which could influence the results. In most cases, to usually be signed and marked according to the standards. however, the Michigan responses did not vary significantly Advisory speeds seem to be determined somewhat consis- from the others. In cases where the responses from Michigan tently within jurisdictions but not among jurisdictions or across were substantially different from the rest of the sample, both a state. The potential differences in procedures for determining sets of responses were examined and reported. advisory speeds notwithstanding, the consensus is that many, The practitioner survey provided some valuable informa- if not most, speed advisories are lower than needed and, most tion about the state of the practice for curve-related TCDs. assuredly, not too high. Questions about consistency in the Based on the relatively high level of response and the numer- use of curve signs and in particular advisory speed signs ous comments made on survey forms, it is clear that the sign- yielded lower response rates. This may be due to the fact that ing and marking of horizontal curves is an issue that many respondents are worried about liability or to the fact that they practitioners find important. However, some responses were are not confident that all the curves in their area have appro- not easily interpreted. For example, one of the primary priate signs or advisory speeds. Respondents did not feel that responses to the question "Which horizontal curves are the curve TCDs were overused, and some even commented that most difficult to sign and mark appropriately?" was "inter- signs might be underused in places. One common observa- section on curve." However, there is a standard intersection- tion was that budget and staff limitations have an effect on on-a-curve sign (W1-10) available in the MUTCD, so it the selection and placement of TCDs on horizontal curves. would be expected that this situation would not be difficult Many respondents pointed out that personnel in many more to sign. It could be that respondents who checked this answer rural jurisdictions know the standards, but do not have the felt that this sign was not adequate for communicating the sit- financial resources, the staff, or the equipment to perform uation to drivers, or they may not routinely use all TCDs at studies and/or place signs. Similar to the focus group results, their disposal. the clear picture that emerged was that rural jurisdictions and Not surprisingly, agencies generally sign their own roads. those with limited budgets have less comprehensive curve- When they do not, it is usually done by a higher government related signing than more urban or richer jurisdictions. authority. While states and counties usually employ engineers When broken down into state and county jurisdictions, and technicians, cities and townships often have other per- answers about signing consistency did not change greatly. sonnel such as a sign manager or road foreman responsible State-level respondents tended to be more uniform and posi- for the selection of TCDs for horizontal curves. The large tive in their answers than were their county-level counterparts, numbers of non-engineers involved in day-to-day signing calls but still had a negative view about practices across the state or to question when, how, and by whom "engineering judgment" at different jurisdictional levels within a state. At the state level,