D. Evidence & Regulations
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Elena Vance, J.D.
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8 min read
Commercial Trailer Underride Guards: Regulatory Standards and Crashworthiness Defects
Underride collisions occur when a passenger vehicle slides beneath a commercial trailer, bypassing standard vehicle crumple zones and airbags. We examine rear impact guard standards under 49 CFR § 393.86.
Key Legal Takeaways
- Federal rear guard standards require energy absorption capable of preventing passenger compartment intrusion at 30+ mph.
- Side underride guards remain unregulated federally but constitute an established basis for common law product liability in Texas.
- Traumatic brain injury and decapitation are the primary hazards in underride wrecks.
Defective Rear Impact Guards and Maintenance Failures
Corroded, bent, or improperly welded rear underride guards shear off during collisions. Motor carriers are mandated by 49 CFR § 396.17 to inspect underride guards annually.