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From page 50... ... However, although some improvements in crash reporting for work zones are evident, more is still needed. Highway agencies have expressed a number of concerns regarding work zone crash data, which can generally be grouped into the following categories: • Lack of consistency and accuracy of police crash databases, • Lack of interoperability between databases, • Lack of timely data, • Lack of work zone information, • Lack of identification of work zone limits, • Lack of ability to know whether or not the work activity had any effect on the crash, and • Lack of identification and assessment capabilities of worker injuries/fatalities. Read the entire page →
From page 51... ... ; • Money spent on construction/maintenance projects; • Duration of work zone; • Total number of miles of work zone; • Number of work zones per type of roadway; • Volume of traffic through the work zone; • Hours of work zone activity without positive protection; • Queue lengths per type of roadway; • Running speed or other traffic operational measures about the work zone; • Frequency of motorists exceeding the posted speed limit; and • Number of erratic/conflict maneuvers in work zones. A detailed list of data elements for work zone crashes is discussed at the end of this chapter. Read the entire page →
From page 52... ... For those states that do adopt the workzone-related data elements recommended in the MMUCC, it would be possible to combine data from multiple states to assess work zone issues of national significance, and it would also permit the comparison of certain work zone safety performance measures between states. State DOT Agency-Based Work Zone Crash Data Reporting Some state DOTs have established an internal crash reporting mechanism in place to capture work zone crash data above and beyond data available from the statewide crash reporting system. Read the entire page →
From page 53... ... Can help improve timely reporting to DOT Includes good basic crash characteristics Identifies additional crash data elements that may be useful in work zone analyses High level of DOT control Can be revised at state level to add elements as needed May be improved at state level to add elements Can be customized to meet specific needs May be linked to roadway, project, and traffic data May be linked to roadway, project, and traffic data May be linked to roadway, project, and traffic data May provide better information that is useful in defense of legal claims Disadvantages Not uniform between states No AASHTO involvement Not uniform between states Requires ongoing enforcement training Requires more training for enforcement personnel Requires development of state procedures Omits industrial accidents Overlooks most minor crashes May miss some events -- nights, weekends Most contain few, if any, work zone characteristics Omits industrial accidents Requires DOT staff training Overlooks most minor crashes Work zone terminology needs "tweaking" Requires DOT management commitment Access to data by DOT is often delayed Access to data by DOT is often delayed Added cost to DOT May lack uniformity within state Should be supplemented by state crash report Table 22. Advantages and disadvantages of available work zone crash data sources. Read the entire page →
From page 54... ... While the MMUCC will provide a greatly improved level of data in most cases, the other necessary terms and conditions listed above for the existing state report forms are also applicable to use the MMUCC data. State Highway Agency-Based Crash Data Collection and Reporting Currently, some states have internal systems in place for collecting work zone crash data elements using their own personnel or contractor personnel at the project sites. Read the entire page →
From page 55... ... Recommended Model Work Zone Crash Report Data Elements, Attributes, and Definitions MMUCC Guideline Data Elements and Attributes -- 2003 Edition The 2003 MMUCC criteria include much of the information that is considered desirable to document work zone crashes in a manner that makes it feasible to manage traffic safety and some aspects of mobility in work zones. A full list of all 111 MMUCC data elements appears in Appendix C; those thought to be most directly critical to work zone management are identified in the column "Work Zone Critical." Several of the 111 elements actually include several subfields, such that the total number of data elements is considerably more than 111. Read the entire page →
From page 56... ... " C13 Roadway Surface Condition One of the available attributes is " mud, dirt, gravel , " which can be used to describe conditions sometim es encountered in work zones. C15 Contributing Circum stances, Road One of the available attributes is " work zone (construction/maintenance/utility) Read the entire page →
From page 57... ... Inherent Limitations in the MMUCC Guideline In addition to the suggested revisions to the 2003 edition of the MMUCC guideline, three inherent limitations were identified that impact its usefulness for managing some aspects of work zone safety, and these limitations may be difficult to overcome within the existing framework of the MMUCC guideline. The most critical limitation is that this guideline focuses entirely on work zone crashes and does not address non-crash events. Read the entire page →
From page 58... ... This limitation is discussed above under the suggested revisions to the definition of "work zone crash." The third significant limitation is that most of the linked roadway data elements RL1–RL18 provide information on roadway features that are also of interest in work zone crashes. However, because these data elements are obtained 58 Element Number Element Name Suggested Attribute Revisions C6 First Harmful Event • While the attribute "thrown or falling object" can be used to describe construction debris, it would be helpful to add an additional new attribute "construction debris/material" for this purpose. Read the entire page →
From page 59... ... Considering these limitations, reliance exclusively upon the MMUCC data elements and state crash report forms may not generate all work zone crash and accident data elements deemed essential to managing work zone safety. Even if all the MMUCC data elements and attributes are adopted by a state and all enhancements suggested in this report to better capture work zone crash data are also adopted, a highway-agencybased reporting system may still be desirable to better capture the full range of data elements considered important. Read the entire page →
From page 60... ... • The unique and cumbersome coding system included in the current program makes it extremely difficult to combine the New York data with data available from other states and other work zone crash data sources. • The coding system also makes it extremely cumbersome to query the database to identify specific crash and accident types and characteristics, other than those specific data elements and attribute factors now included in the reporting program. Read the entire page →
From page 61... ... Recommended Work Zone Crash Data Analysis Methods In the most general terms, work zone crash data can be used for ongoing monitoring functions or for detailed afterthe-fact (post-hoc) investigations to quantify and/or test the statistical significance of various crash-related hypotheses. Read the entire page →
From page 62... ... that may be unduly contributing to crashes occurring in work zones and so need to be modified. Posthoc investigations are more suited to actually quantifying the extent to which those features and operating strategies are contributing to work zone crashes and to quantifying the extent that any modifications made to them are actually reducing crash risk. Read the entire page →
From page 63... ... In addition, there are insufficient elements to identify all of the specific types of work zone traffic control devices and safety features present or involved in the crash, other than a few included in other data elements such as "Traffic Control Device Type." In addition, there are no elements to describe work vehicles, equipment, and work operations. These lacking data elements can best be addressed by developing a comprehensive list of data elements and attributes to be incorporated into a work zone crash/accident reporting program to be implemented by highway agencies as a supplement to MMUCC or similar crash reports. Read the entire page →
From page 64... ... Therefore, it is important to duplicate certain data elements from the MMUCC into the work zone crash/accident reporting program to ensure that the necessary information is available in a timely manner for all events. These elements are identified in the column "Work Zone Related" in Appendix C Read the entire page →

From page 50...

... However, although some improvements in crash reporting for work zones are evident, more is still needed. Highway agencies have expressed a number of concerns regarding work zone crash data, which can generally be grouped into the following categories: • Lack of consistency and accuracy of police crash databases, • Lack of interoperability between databases, • Lack of timely data, • Lack of work zone information, • Lack of identification of work zone limits, • Lack of ability to know whether or not the work activity had any effect on the crash, and • Lack of identification and assessment capabilities of worker injuries/fatalities.