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Importance of a Truck’s “Black Box”

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Most commercial trucks are equipped with “black boxes,” also known as electronic control modules (ECMs) or event data recorders (EDMs). Many national and regional carriers also utilize satellite tracking equipment or data recorders to track their fleet.

To understand the importance of ECMs and EDRs in relation to litigation, it makes sense to review what data these pieces of equipment record. An EDR device stores data about the physical properties of a vehicle that is involved in an “event,” such as an accident or near-accident. 

In 2011 the National Highway Traffic Safety Administration (NHTSA) issued a rule requiring EDRs to record certain data (the “Final Rule”). Under the Final Rule, an EDR must include at least the following:

  • Vehicle speed (5 seconds before impact)
  • Engine throttle (5 seconds before impact and determines if the accelerator was pressed)
  • Brake use (5 seconds before impact)
  • Delta-V/Change in velocity (for up to 3 seconds after impact)
  • Seatbelt use for the driver
  • Driver front airbag deployment
  • Right front passenger airbag deployment
  • Number of impacts/crash events
  • Time between crash events/impacts if applicable
  • Whether the EDR completed its recording

This information can be transferred immediately to a “home base” via satellite for trucks equipped with global positioning satellite systems.

In the event of an accident, this data should be made available to your attorney as soon as possible so that it can be preserved and used as evidence, if needed. Over 500,000 trucking accidents occur every year in the U.S. Approximately 5,000 of these accidents result in fatalities and many more in personal injury or property damage.  In some situations, ECMs/EDRs can help provide additional evidence alongside police and EMT reports, witness statements, and photographs.

While federal regulations don’t yet require trucks to be equipped with an EDR, almost all truck engines are equipped with an ECM that functions as an EDR. An ECM is standard on all diesel fuel-injection systems. ECMs allow companies to monitor and evaluate trip times, speeds, total idle time, and the number of “hard” stops, which can help a company determine driving habits in relationship to safety, fuel consumption, and engine wear and tear.

In the event of an accident or near-accident, it is important any available information from an ECM or EDR are transferred to your attorney. This information can be overwritten if the vehicle is moved or operated after the accident, so best practice requires contacting your “home base” and attorney as soon as possible after an incident.

Even well-trained drivers can have accidents. Murphy Legal has extensive experience with preserving and defending black box data. If you or your company are facing a legal claim due to a trucking accident, Murphy Legal is ready to defend you. To learn more about our passion for the trucking industry, call us at (979) 690-0800 or contact us.

If you need assistance in an emergency, call our 24-Hour Emergency Hotline at 979-209-2173. We’re here to help.

Be sure to check our Refuel blog series for additional resources and information about rig and driver safety.  Click here to sign up for our newsletter covering a wide variety of topics to help protect owner-operators and trucking companies from liability in the event of an accident.


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