Vehicle speed plays a central, powerful role in the safety of pedestrian and bicyclists. Studies suggest that even a modest reduction in average vehicle speed can result in significantly fewer and less severe bicyclist and pedestrian crashes. A comprehensive study by the AAA Foundation concluded that an adult pedestrian struck by a motor vehicle traveling at 25mph has a roughly 10% chance of suffering a serious or fatal injury. Yet if a driver hits an adult pedestrian at 40mph, there is a 75% chance that the pedestrian would incur a severe or fatal injury. Moreover, as the Insurance Institute for Highway Safety (IIHS) has recently reported, the recent national rise in pedestrian fatalities is at least partially attributable to increased use of sport utility vehicles (SUV) and high horsepower vehicles.

Like most persistent traffic safety problems, speeding is a complex and situation-specific issue. In diverse communities across the United States, it is generally socially acceptable to speed in some areas (e.g., on cross-town arterials roads) and not in others (e.g., near schools). Not only that, drivers are often in a rush to reach their destinations. Given the complex nature of speeding, a comprehensive approach to managing speed is recommended for agencies and the communities they serve. Strategies include roadway design and adjacent land uses to naturally calm traffic, lower speed limits, high-visibility and automated speed enforcement operations, as well as roadway lighting improvements to create safer environments for bicycling and walking.


National Association of City Transportation Officials' (NACTO's) City Limits outlines how to use a tested, context-sensitive safe systems approach to strategically set safer speed limits on urban streets to reduce traffic fatalities and injuries.

Institute of Transportation Engineers (ITE) Speed Management Resources presents a compendium of guides, policies and practices related to managing traffic speeds.

The National Traffic Safety Board (NTSB) Reducing speeding-related crashes involving passenger vehicles examines causes of and trends in speeding-related passenger vehicle crashes and countermeasures to prevent these crashes, and proposes a five-point series of interventions to curtail excessive speeds: (1) speed limits, (2) data-driven approaches for speed enforcement, (3) automated speed enforcement, (4) intelligent speed adaptation, and (5) national leadership.

Managing Speed demonstrates how excessive and inappropriate speed is among the key risks for road traffic deaths and injuries worldwide and illustrates how safe speeds are among main components of a safe systems approach to road safety.

The European Commission's Road Classification provides guidance on developing and implementing clear, consistent road classifications that link road design to its intended function throughout entire roadway networks.

Road Safety Toolkit includes a chapter on speed management, which features engineering countermeasures designed to manage vehicle speeds, such as gateway treatments, roundabouts, and raised platforms.

Every Day Counts Safe Transportation for Every Pedestrian (STEP) program provides guidance on implementing speed- and crash-reducing pedestrian safety countermeasures, such as road diets and raised crosswalks.

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Taming Speed for Safety presents a case study highlighting efforts in Portland, OR to change upstream policy and design strategies to encourage safe speeds that result in safer conditions for all roadway users.

Drive 25: It's the Law! Campaign in New York City encourages drivers to drive the posted 25mph speed limit.

Study evaluates the effects of the speed limit reduction from 30mph to 25mph on speeds in Boston, Massachusetts.

How Walk Friendly Communities Manage Speed shares speed management strategies and approaches.

Frequently Asked Questions on Speed in the City of Seattle, Washington covers speed limit reduction and vision zero initiatives.

Camera Radar Speed Enforcement program shares state laws regarding speeding and enforcement efforts to manage speed.

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