Since the mid-seventies, the Federal Highway Administration (FHWA) has endorsed crash cushions for absorbing energy during traffic collisions. The original concept of these barriers full of rubber was pioneered by Goodyear Tire & Rubber Company. This evolving innovation has contributed to saving lives as well as reducing car and road damage. Here are key economic, safety and environmental benefits of the various types of crash cushions.
A wide range of crash cushions are available for government agencies and other organizations. The three main categories of these energy absorbing devices are called RGM, RLM and NRS.
RGM stands for “redirecting with repair costs greater than $1,000” while RLM means “redirecting with repair costs less than $1,000.” NRS, which is the more affordable option using sand barrels, refers to “nonredirecting sacrificial” systems. This model, however, is not the most cost-effective long-term solution.
Rural road testing of these three groups and cost-benefit analysis have shown that RGM and RLM are the most cost-effective solutions for freeways and divided rural roads. Since crash cushions reduce road cleanup, they help cut down maintenance costs.
One way for local governments to make roads safer is to conduct studies on traffic areas to learn where collisions occur most often. This knowledge helps lead to solutions that reduce accidents, fatalities and injuries. New York City, for example, has successfully reduced car and pedestrial fatalities in recent years based on NYCDOT collision data that pinpoints locations of danger areas. In this case, the solution was to install speed cameras and emphasize law enforcement.
Cameras help deter speeding and evidence collection but they don’t necessarily prevent crashes caused by drunk drivers or other careless individuals who may be distracted by a mobile device or roadway imagery. Crash cushions do something that cameras cannot, which is reduce the impact of a head-on collision.
The story of the crash cushion originated with Goodyear’s research on how to efficiently dispose of tire scraps. They decided to test them in barrels as shock absorbers for car collision experiments with crash test dummies. The tests proved these cushions reduced damage to vehicles and passengers. Since then, various recyclable materials such as aluminum cans, water and sand have been used as energy absorbers.
Among the most advantageous places for cash cushions are near freeway exits or splits. These areas are where high speed collisions occur and often result from a driver changing their mind at the last second without checking for safety. These safety devices can also be placed along guard rails on high mountain roads, in sections between opposing traffic or near road crews.
It’s possible for cushions to reduce problems Arizona has had with crashes in roundabouts. Part of the problem is that the symbol for a roundabout on City of Phoenix signs looks like a question mark to travelers who aren’t familiar with the concept of circular roads with multiple intersections. Adding to the confusion, is some roundabouts have more than one lane, while studies have shown single-lane roundabouts have less accidents.
Perhaps Phoenix and other cities with multiple roundabouts will consider installing crash cushion systems and electronic communication devices to help make these otherwise visually appealing roads safer. Several models are designed to be mobile and temporary, which is useful for safety testing.
Regardless of how unique or practical a street layout is, every city can benefit from investing in crash cushions, particularly on freeways. Contact Zumar at our Arizona, California or Washington location to learn more about why crash cushions are a worthwhile investment in public safety.