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Chapter Five. Challenges and Conclusions

Factors Affecting CMV Safety

This report identifies safety infrastructure improvements and practices that are being deployed and show promise for improving CMV safety outcomes. The future of CMV safety may also be affected by a number of unpredictable trends:

Economic Trends

The following changes in freight demand and in trucking industry capacity are expected in the near term (1 to 3 years):

As FHWA works with States to conduct the freight planning required by the FAST Act and updates its own national strategic freight plans, FHWA can help States adopt scenario plans for these and other changes in CMV traffic that will be critical to inform State SHSPs and financially constrained freight project plans.

Changes in highway financing could also affect truck VMT and industry capacity. Many States have been experimenting with road user fees, which are highway funding mechanisms to replace or augment motor fuel taxes and vehicle registration fees. Tests of such systems have been encouraged in previous surface transportation reauthorizations, and section 6020 of the FAST Act also establishes a grant program to assist States in testing user-based alternative revenue mechanisms. Since combination trucks travel more miles per vehicle than autos or single-unit trucks, any user-based fee is likely to charge large trucks more, as is already the case with per-gallon motor fuel taxes. If new user-based alternative funding mechanisms increase the relative share of user fees paid by CMVs, the economics of longer-distance truck trips may change. This could lead to either pressure for longer combination vehicles to gain more productivity from mileage-based fees assessed on the tractor unit or more truck-to-rail diversion of intercity trips Either of these outcomes could have implications for CMV safety.

Potential Future Safety Practices

This report has described a number of roadway infrastructure safety improvements, but some incremental adjustments could increase their safety benefits. The following examples of possible alterations to current practices could be explored with existing or new technologies:

Freight and Safety Planning Responses

The subject of CMV safety also raises issues beyond the scope of this report that the transportation safety community can consider as the FAST Act is implemented. Pertinent stakeholders include policy makers, modal administrations in DOT, State infrastructure owners, law enforcement agencies, industry associations, vehicle and traffic safety equipment manufacturers, and transportation research institutions. These safety issues include the following:

Freight and safety planning integration. Congress has authorized the designation of the Primary Highway Freight System and mandated State freight planning after October 2017 that will identify State-specific highway freight networks. Collection of traffic safety data on these corridors could help inform data-driven safety planning at the State level, such as during the SHSP process. In addition, as States identify projects to improve freight operations on these corridors, they should consider safety outcomes on these freight highway networks.

Truck size and weight issues. Section 32801 of the Moving Ahead for Progress in the 21st Century Act required DOT to conduct a comprehensive truck size and weight limits study. The April 2016 report addressed five core technical areas and concluded that data gaps and model limitations prevented a conclusive, bottom-line finding. Without this definitive conclusion, certain shippers and motor carriers have advocated adjustments to the Federal truck size and weight limits (e.g., longer combination vehicles within current weight limits and heavier trucks with different axle configurations) in the FAST Act authorization and annual appropriations deliberations. The CMV safety measures in this report are responsive to the current CMV fleet (even with regional size and weight variations authorized in current law). Changes to truck size and weight restrictions may alter CMV safety outcomes and require different practices.

Findings and Conclusions

Infrastructure will always be critical to the safe and efficient operation of the Nation's highway system The goal of no fatalities cannot be achieved by focusing on infrastructure alone, so Congress requires State SHSPs to address six elements of highway safety as key factors in evaluating highway projects:

States are currently deploying a number of infrastructure safety measures identified with varying degrees of demonstrated effectiveness in addressing CMV safety needs. The safety improvements and practices included are not limited strictly to pavements and bridges but also consider roadside hardware, capacity improvements, signage and markings, better work zones, and ways the infrastructure can support safety enforcement efforts. While standard safety design practices and traffic engineering work well on large portions of the systems, enhanced measures can be used in areas of greater risk. Dynamic signing, higher-performing barriers, and detection systems are examples. Technology is playing a greater part in safety every year as more concepts emerge as practical applications to provide smarter vehicles and smarter infrastructure The countermeasures described in this report fall within the engineering, management, operations, and enforcement elements.

Each State will continue to identify emphasis areas, strategies, and goals through a collaborative planning process with multiple stakeholders. Beginning in 2017, States will also establish annual targets for fatalities and injuries to measure safety performance. The CMV-related emphasis areas are already included in over half of the State SHSPs. Since 12 percent of all traffic fatalities involve large trucks and buses, State data-driven approaches may focus on many other crash and casualty issues and factors. However, with the vision of zero deaths embraced by FHWA and most State DOTs, CMV safety will continue to be part of reaching this goal.

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Page last modified on June 21, 2017
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