Proven Safety Countermeasures – Part 2

Last week’s blog, we reviewed the first 5 proven safety countermeasures which were established by the Federal Highway Administration (FHWA) in January 2012. This week, we’ll review the remaining four proven safety countermeasures which focus on using a data driven approach to improve road safety and reducing fatalities on American highways.

Medians and Pedestrian Crossing Islands in Urban and Suburban Areas

According to the Federal Highway Administration (FHWA), pedestrians struck by vehicles travelling at 40 mph (approx. 65 km/h) have a 20% survival rate while vehicles travelling at 20 mph (approx. 32 km/h) have a 90% survival rate.

Installing pedestrian crossing islands and medians help alert drivers to slow down and decrease crashes and the severity of accidents. Pedestrian crossing islands have demonstrated a 46% reduction in pedestrian crashes while medians at unmarked crosswalks have demonstrated a 39% reduction.

Pedestrian crossing islands have a number of safety benefits:

  • Reducing pedestrian crashes by 46%
  • Decreased motorist delay by 30%+
  • Enhanced visibility of pedestrians and pedestrian crossings
  • Reduced speeds in pedestrian crossing island areas
  • Enhanced access management
  • Additional space for supplemental signage on multi-lane roadways

 

Safety EdgeSM

The FHWA states that vehicle crashes involving edge drop-offs or vertical pavement edges are two to four times more likely to result in a fatality than other crashes on similar roads. These vertical pavement edges are a contributing factor to severe crashes that usually involve head-on crashes or rollovers.

Safety EdgeSM is a paving technique created to provide a gentle slope to facilitate re-entry onto the roadway. It creates a durable 30° angle which prevents tire scrubbing against asphalt and concrete payments, which is what contributes to losing control of a vehicle. FHWA studies have shown an estimated 6% reduction in vehicle crashes on two-lane highways and encourage deployment through the FHWA’s Every Day Counts initiative.

 

This is a diagram of how Safety Edge is applied onto a 30 degree angle between the new and old pavement as well as the new and old graded material.

Pedestrian Hybrid Beacon

Midblock locations account for more than 70% of pedestrian fatalities due to faster vehicle speeds. These faster speeds contribute to a higher injury and fatality rate in these areas. Utilizing a pedestrian hybrid beacon, also known as also known as the High Intensity Activated Crosswalk (HAWK), provides a visual warning to approaching vehicles. It has been shown to provide a 69% reduction in pedestrian crashes and a 29% reduction in total roadway crashes.

According to the FHWA, this safety countermeasure is fairly new and it is suggested that pedestrian hybrid beacons should only be used alongside marked crosswalks. Also, these beacons should be used if gaps in traffic are not adequate to permit pedestrians to cross, if vehicle speeds on the major street are too high to permit pedestrians to cross, or if pedestrian delay is excessive.

Areas with a high amount of pedestrians such as schools and transit locations are also appropriate areas to use these beacons. For additional deployment information, refer to the Manual on Uniform Traffic Control Devices, Chapter 4F.

 

Road Diet

A “road diet”, also known as roadway configuration, is the process of reducing an undivided four lane roadway into three lanes where the centre is a two-way left-turn lane sandwiched by two through lanes. Usually it seems that reducing lanes would be counterproductive, but the additional roadway space allows for the installation of bike lanes, pedestrian crossing islands, or on-street parking.

The FHWA has found that reconfigured roadways, specifically four lanes to two travel lanes with a two-way left-turn lane, demonstrate a 29% reduction in total roadway crashes. Ideal roadways for reconfiguration have an Average Daily Traffic (ADT) of 15,000 or less and have been found to produce good results in relation to safety, operations and livability.

Reconfigured roadways have multiple safety benefits:

  • Reduced the number of travel lanes for pedestrians to cross
  • Ample space for pedestrian crossing island installation
  • On-street parking which is a buffer between the roadway and pedestrians/cyclists
  • Reduced rear-end and side-swipe crashes
  • Decreased severity of crashes
  • Increased compliance to speed limits

 

This is a comparison showing the before and after of a roadway reconfiguration or “road diet”.

Data Driven Approach to Safety

The FHWA states that these safety countermeasures were updated from 2009 and emphasize a data driven approach in order to improve safety on American highways. Utilizing data to understand traffic volumes, traffic movements and the incident and crash reports provide engineers with insight into the functionality of the roadways. This information is vital in addressing the needs of the roadways, intersections and the individuals who use them.

Accurate data that is timely and auditable seems to be invaluable for traffic engineers. Miovision provides traffic data collection equipment, the Scout, which is the industry’s leading video data collection unit. It delivers 95%+ accuracy for turning movement counts (TMCs) within a convenient turnaround time. Access to our online traffic data management portal, TrafficDataOnline.com, provides traffic engineers with the tools they need to organize and manage all of their traffic data, reports and videos.