Event Data Recorder (EDR)
When an Absence of Evidence is Evidence
In moderate and high-speed collisions it is well known that Event Data Recorders, aka black boxes, record data that can provide valuable insight into the vehicle dynamics before and during the collision (e.g. speed, braking, velocity change, acceleration profile, seat belt use, etc.) and assist experts in their accident reconstruction analyses. 

  • Question: But what can the EDR tell us when a vehicle is involved in a low-speed accident and no data is recorded?
  • Answer: The lack of data is data that can tell us something about the collision. 

The National Highway Traffic Safety Administration (NHTSA) Part 563 Event Data Recorder (EDR) Standard states a vehicle’s EDR needs to record specific data elements when that vehicle experiences a longitudinal Delta-V (velocity change) of 5 mph or greater within a time frame of 150 msec. In several recent cases Vector Scientific, Inc. (VSI) has downloaded either the striking vehicle or struck vehicle that were involved in minor collisions and found that no data had been recorded. Using the Crash Data Retrieval (CDR) Data Limitations information and knowing that the subject vehicles were Part 563 compliant, Senior Engineer Zach Weimer, P.E. was able to conclude that these vehicles with no recorded events had never experienced a longitudinal Delta-V of 5 mph or greater.  Knowing this piece of the puzzle for one car then permits traditional reconstruction methods to determine the collision severity for all vehicles involved. 

Please contact Zach regarding Event Data Recorder (EDR) questions and traffic accident reconstruction issues in your case. 
Call us at 303-697-9977, email us at information@vectorscientific.com, or visit our website at www.vectorscientific.com to learn more on how our services can help you and your clients.