More than half of all new cars sold in the United States have event data recorders, or EDRs, that investigators can use to peer into the crucial seconds before and during crashes for information like vehicle speed, braking, belt use, and impact severity. New federal rules, effective for 2011 passenger vehicle models, are expected to broaden EDR usefulness by standardizing the data that are collected. But the rules fall short of requiring EDRs.
"There are things EDRs can tell you about a crash that investigators can't," says Susan Ferguson, Institute senior vice president for research. "The new rules are going in the right direction by requiring the collection of uniform data, but the government should have gone further and mandated EDRs in all new passenger vehicles."
EDRs extend the information from airbag crash sensors, which measure vehicle decelerations to determine if a serious crash is occurring and whether airbags should inflate. The EDR gathers information from these sensors and in some cases from other vehicle systems, storing it in its memory in the event of a crash.
These devices have grown more sophisticated with new airbag technologies. EDRs are used in some manufacturers' automatic systems that notify call centers when serious crashes occur.
The information EDRs collect varies by automaker, and data retrievability is mixed. The federal rules aim to not only standardize the data but also make it easier for researchers, law enforcement personnel, and others to download the information. The government directed the manufacturers to ensure by licensing pacts or other means that technology is commercially available to retrieve the data from EDRs. And for the first time automakers will have to tell consumers if the vehicles they're buying are equipped with EDRs, satisfying some concerns about privacy.
Under the new rules, EDRs have to record a minimum set of specified data in a uniform format to answer questions about crash severity, vehicle dynamics, and safety systems up to five seconds before impact and a third of a second afterward. Did the driver apply the brakes? How fast was the vehicle going? Was the driver's safety belt buckled? What was the maximum speed change of the vehicle during the impact? If an EDR records more information, such as steering before impact and whether electronic stability control was operating, the rules specify the format and time period for recordation.
Investigators and insurers can use objective information like this to get a better understanding of what's happening before and during collisions and to secure more reliable and complete measures of the severity of crashes. In some cases, EDRs also can help to determine who's culpable in crashes.
Regulators say they didn't feel compelled to require EDRs in all new passenger vehicles because about 64 percent already have them. This is expected to grow to 85 percent by the 2010 model year.
Ford, General Motors, Isuzu, Mazda, Mitsubishi, Subaru, and Suzuki voluntarily equip all of their passenger vehicles with EDRs (information as of 2005 models). More than half of all Toyotas have EDRs. Other vehicle manufacturers, mostly German and Korean plus some Japanese, don't bother. Vehicles from BMW, Daewoo, Honda, Hyundai, Kia, Mercedes, Nissan, Porsche, and Volkswagen don't have EDRs, according to federal estimates.
"It makes no sense for EDRs not to be in every new vehicle, whether automakers voluntarily install them or the government tells them to," Ferguson says. "The information EDRs can provide is critical in understanding how people are injured in crashes, especially as auto manufacturers incorporate more sophisticated technologies into their fleets. If EDRs were standard equipment, researchers as well as the automakers themselves would have a wider pool of reliable data to help evaluate occupant protection technologies and answer other crashworthiness questions."
The federal rules cover EDR-equipped passenger vehicles that are manufactured after September 2010. Certain manufacturers will get a year's extension. The National Highway Traffic Safety Administration, which issued the rules, says that "with certain modest modifications, many current EDR systems can meet our goals of facilitating [automatic crash notification] and improving crash reconstructions."
What's an EDR?
Popularly called a "black box," an event data recorder (EDR) collects certain information from a vehicle immediately before and during a crash or near-crash — not all crashes but most of the serious ones. An outgrowth of airbag control modules, some recorders indicate only whether the airbag was properly armed and whether there was a signal to inflate. These devices aren't considered true EDRs, so they aren't covered under the government's new rules. Devices that record vehicle speed before a crash or speed change during the impact are defined under the federal rules as EDRs.
Are all EDRs alike?
No, those in current models vary in terms of the information they collect. Under the federal rules that will apply to 2011 and later models, devices defined as EDRs must record 15 data elements, including vehicle deceleration, in specific formats. More advanced EDRs may record information from the engine control module, antilock brakes, and other systems. Advanced EDRs also may log more information during a crash including, for example, time from impact to frontal airbag deployment, deployment level, and time from impact to maximum velocity change.
Who owns the data? Who has access?
EDRs and the data they store belong to vehicle owners. Police, insurers, researchers, automakers, and others may gain access with owner consent. Without consent, access may be obtained through a court order. For crashes that don't involve litigation, especially when police or insurers are interested in assessing fault, the insurers may be able to access the EDRs in their policyholders' vehicles based on contract provisions. However, some states prohibit the contracts from requiring policyholders to consent to access.
Are EDRs used for crash notification?
Automatic notification systems are designed to alert emergency responders, including police and medical personnel, when crashes occur. These systems use data from EDRs, airbag sensors, and global positioning systems to identify the occurrence of crashes, their severity, and the location of involved vehicles. This information is sent by cellphone to emergency dispatchers or to a private call center that forwards it to local 911 operators.