Work Zones

SECTION III

Type of Problem Being Addressed

General Description of the Problem

The safe and efficient flow of traffic through work zones is a high priority for transportation officials and the motoring public. In a recent survey, work zones were cited as second to poor traffic flow in causing dissatisfaction with roadway facilities (Keever et al., 2001). Exhibit III-1 indicates that work zones are estimated to contribute to 10 percent of the congestion in the United States. This is a rough estimate based upon a variety of congestion research sources. Although mobility may be the issue most often associated with work zones, mobility and safety are linked. The Federal Highway Administration has stated that as congestion builds within and approaching work zones, crash rates increase (FHWA, 1998).

In 2003, there were 919 fatal crashes (1,028 fatalities) and more than 40,000 persons injured in work zone crashes on America?s highways (FARS, 2005). Exhibit III-2 displays a trend of increasing deaths attributed to work zones over the last 7 years. During this timeframe, anecdotal evidence suggests that the number of work zones have increased, although no definitive evidence or study encompasses all types of work zones. As more and more of the nation?s infrastructure reaches the end of its life cycle, work zones are expected to remain a familiar sight on our roadways.

Exhibit III-3 shows the distribution of work zone types in which fatal crashes occurred in 2003. The preponderance of crashes occurred in long-term construction zones. Issues faced by drivers may vary by type of work zone, and safety improvements for all types of work zones are considered in the strategies discussed in Section V. Despite the large number of reported work zone fatalities, there is a general sense that the scope of the problem may be much worse, as there are many inconsistencies in defining and reporting work zone crashes from state to state.

The safety of roadway construction workers in work zones is also of primary importance. According to an American Road and Transportation Builders Association (ARTBA) review of federal data from the Bureau of Labor Statistics, roadway construction workers are killed at a rate nearly three times as high as other construction workers and eight times as high as general industry workers. The fatality rate for roadway construction workers is 32 people for every 100,000 workers. By comparison, the rate for all construction is about 13 people per 100,000 workers, and the general industry rate is about 4 people per 100,000 workers (ARTBA, 2004).

The need for continued emphasis on work zone safety becomes more apparent because of the current emphasis on system preservation rather than construction of new facilities. Funding patterns support this point, as the U.S. Department of Transportation reports that the share of transportation capital funds used for system preservation rose from 47.6 percent in 1997 to 52.0 percent in 2000, and this percentage increase is expected to continue.

EXHIBIT III-1
Sources of Congestion
Traffic Congestion and Reliability, 2004

System preservation—reconstruction of an existing roadway—is inherently more risky for both construction workers and roadway users than construction on new alignment. The prevalence of work zones on the roadway network may be best described by Wunderlich and Hardesty (2003), who report that about 20 percent of the National Highway System is under construction each year during the peak summer road work season, with the total number of highway work zones estimated to be more than 6,400. This study collected project information posted on agency websites, and these websites would most likely list only large projects rather than a complete list of all projects. Had the websites listed all projects, the types of work zones would be much more numerous, especially considering the presence of short-term work zones, including utility, maintenance, and emergency activities.

EXHIBIT III-2
Number of Work Zone Fatal Crashes and Fatalities, 1994?2003

EXHIBIT III-3
Work Zone Fatal Crashes by Work Zone Type in 2003

Specific Attributes of the Problem

Data from the Fatal Accident Reporting System (FARS) were reviewed in an attempt to characterize differences between work zone crashes and non?work zone crashes. Exhibit III-4 compares several factors that relate to work zone and non?work zone fatal crashes.

Based on a review of the above table, a few general statements can be made about the nature of work zones and their affect on traffic fatalities in 2003:

• More than half of all fatal work zone crashes occurred during the day. According to Wunderlich and Hardesty (2003), approximately 22 percent of the work zones that they found listed on agency websites were designated for night work, and two-thirds of all resurfacing and paving activity took place at night.
• More than twice as many work zone fatal crashes occurred on weekdays as on weekends.
• Fatal work zone crashes occurred most often during the summer months, followed by the fall and spring months, presumably when the majority of construction activities are taking place in large portions of the country.
• Almost 30 percent of work zone fatal crashes occurred on either urban or rural Interstates. Overall, slightly more fatal crashes occurred in rural work zones than in urban work zones.
• Almost 60 percent of work zone fatal crashes occurred on roads with a posted speed limit of 55 mph or greater.
• Single-vehicle crashes accounted for more than half of all work zone fatal crashes.
• Rear-end fatal crashes were about 2.7 times as common in work zones as in all fatal crashes.

EXHIBIT III-4
Comparison of Factors: Percentages of Work Zone and Non?Work Zone Fatal Crashes
Data from FARS (2003)

Other points regarding work zone safety include the following:

• Ninety percent of work zone fatal crashes involved vehicle drivers or occupants. Approximately 10 percent were pedestrians and bicyclists (FARS, 2003).
• Heavy trucks were involved in more than 20 percent of fatal work zone crashes (FMCSA, 2004).
• Alcohol was involved in 39 percent of fatal work zone crashes in 2003 (National Work Zone Safety Information Clearinghouse, http://wzsafety.tamu.edu/index.stm).

A broad range of engineering enforcement, education, and agency policy strategies are available (and discussed in Section V) and the potential to significantly improve work zone safety for workers, motorists, and other highway users. These safety strategies also link to guides in the NCHRP Report 500 series already developed (or being developed) to address other priority areas in the SHSP.

Key References

AARTBA (American Road and Transportation Builders Association). April 6, 2004. "Roadway Construction Workers at Higher Risk Federal Government Data Show, ARTBA Programs Aim to Improve Worker Safety." News Release. http://wzsafety.tamu.edu/press/artba_4_6_04.stm

Cambridge Systematics, Inc. (with Texas Transportation Institute). July 19, 2004. Traffic Congestion and Reliability: Linking Solutions to Problems, prepared for Federal Highway Administration, final report. http://ops.fhwa.dot.gov/congestion_report_04/index.htm

DHHS/NIOSH (Department of Health and Human Services/National Institute for Occupational Safety and Health). Building Safer Highway Work Zones—Measures to Prevent Worker Injuries from Vehicles. Publication No. 2001-128.

FARS (Fatality Analysis Reporting System). January 2005. Web-Based Encyclopedia. National Highway Transportation Safety Administration. http://www-fars.nhtsa.dot.gov

FARS (Fatality Analysis Reporting System). 1994-2003. 1994-2003 Alcohol Related Work Zone Fatalities. NHTSA. http://wzsafety.tamu.edu/crash_data/alcohol_fatality.stm

FHWA (Federal Highway Administration). September 1998. Meeting the Customer?s Needs for Mobility and Safety During Construction and Maintenance Operations. Office of Program Quality Coordination, FHWA-PR-98-01-A.

FHWA (Federal Highway Administration). 2004. Work Zone Facts and Statistics. http://ops.fhwa.dot.gov/wz/resources/facts_stats.htm

FMCSA (Federal Motor Carrier Safety Administration). April 2004. Large Truck Crash Facts 2002. U.S. DOT. Analysis Division.

Keever, D.B., K. Weiss, and R.C. Quarles. 2001. Moving Ahead: The American Public Speaks on Roadways and Transportation in Communities. FHWAOP-01-017. National Transportation Library, FHWA, U.S. Department of Transportation. http://ntl.bts.gov/lib/10000/10300/10320/movingahead.pdf

Laborers? Health and Safety Fund of North America. August 1998. "Road Construction Hazards Fact Sheet." Washington, D.C. http://wzsafety.tamu.edu/files/factsheet.stm

Wunderlich, K., and D. Hardesty. 2003. "A Snapshot of Summer 2001 Work Zone Activity Based on Information Reported on State Road Closure and Construction Websites." EDL 13793. National Transportation Library, FHWA, U.S. Department of Transportation. http://www.itsdocs.fhwa.dot.gov//JPODOCS/REPTS_TE//13793.html