By :Douglas A. Petho
Unless you are fortunate enough to have a videotape of an accident, a great deal of effort is often spent trying to reconstruct the facts of a collision. Usually, despite doing the best investigation, questions remain exactly how or why a crash occurs. Answers to many of these questions will soon be available from data of contained from the “event data recorders” otherwise known as “EDT’s”.
EDt’s are nothing new. The National Highway Traffic Safety Administration (NHTSA) estimated that about 64 percent of 2005 model passenger vehicles had the devices. By 2005, General Motors, Ford, Isuzu, Mazda, Mitsubishi, Subaru, and Suzuki were all voluntarily equipping all of their vehicles with EDRs, According to NHTSA, these devices are standard equipment from manufacturers including Chevrolet, Ford, Mazda, Mitsubishi, Subaru, General Motors, Isuzu, and Suzuki. The problem has been being able to gain access, understand, and use this information. With no standardized format, proprietary software and a wide variation in the types of information that were actually recorded, their usefulness has been limited.
In August 2006, NHTSA issued an EDR rule that will apply to 2013 and later models. While the rule does not require EDR’s, the rule standardizes the information that the EDT collect and will make access to that information easier. The rule sets out 15 types of information that each unit will be required to record. That information will include:
Change in forward crash speed
Maximum change in forward crash speed
Time from beginning of crash at which the maximum change in forward crash speed occurs
Speed vehicle was traveling
Percentage of engine throttle, percentage full (how far the accelerator pedal was pressed)
Whether or not brake was applied
Ignition cycle (number of power cycles applied to the EDR) at the time of the crash
Ignition cycle (number of power cycles applied to the EDR) when the EDR data were downloaded
Whether or not driver was using safety belt
Whether or not frontal airbag warning lamp was on
Driver frontal airbag deployment: time to deploy for a single stage airbag, or time to first stage deployment for a multistage airbag
Right front passenger frontal airbag deployment: time to deploy for a single stage airbag, or time to first stage deployment for a multistage airbag
Number of crash events
Time between first two crash events, if applicable
Whether or not EDR completed recording
There are still limitations however. Some EDRs restrict data retrieval to the maker of the vehicle. In some instances, the data recorder does not survive the crash itself, in 2005, NHTSA reviewed the results of 37 crash tests in vehicles equipped with EDRs and found that the majority of EDRs didn’t record the entire crash event.
Also, there are privacy concerns since the owner of the vehicle owns the data, then gaining access may be an issue. Nevertheless, NHTSA’s efforts to standardize both the format and content of these devices could provide a valuable tool for those of us seeking to understand and investigate accidents.