Air Bags Expert Witness

Overview

About Air Bags Expert Witnesses

An air bag expert answers whether the restraint system did what it should have done in this crash, and whether a different result would have changed the injury. Three failures come up most: the bag did not fire when it should have, it fired when it should not have or too late, or it fired and caused harm itself. Each requires a different analysis, and each starts with what the crash actually was, not with whether the bag deployed.

The starting fact surprises many clients. An air bag that stayed folded is not necessarily defective. NHTSA describes frontal and side air bags as generally designed to deploy in moderate to severe crashes, while noting they may deploy even in a minor crash ¹. It also calls them supplemental protection, designed to work best with seat belts ¹. So the expert first establishes crash severity, direction and the position of the occupant, and then asks whether the system's own logic should have commanded deployment.

The Federal Standard

Federal Motor Vehicle Safety Standard 208, at 49 CFR 571.208, specifies performance requirements for protecting vehicle occupants in crashes ². Its stated purpose is to reduce deaths and injury severity through crashworthiness requirements measured in forces and accelerations on test dummies ². Compliance is shown in defined tests, and the expert must recognize how far that goes. A real crash will rarely match a test. Meeting the standard is therefore evidence, and how much weight it carries in a design claim depends on state law.

What the Record Shows

The investigation has physical and electronic sides:

• The control module. On vehicles with an event data recorder, required data includes delta-V, safety belt status, the frontal air bag warning lamp, and time to deploy ³
• The warning lamp. The lamp is a readiness indicator and may also signal a malfunction elsewhere in the system, so its history matters ³
• The hardware. Sensors, wiring, the steering wheel clock spring, seat position sensors, and the inflator and module themselves
• The vehicle. Crush profile, occupant contact marks, and whether the bag was previously deployed and replaced

That last point often decides a case. Used vehicles may have been repaired after a prior crash. NHTSA has warned that substandard, dangerous inflators made in China have caused deaths and injuries in the United States ¹. A title history and repair invoice can move the claim from the manufacturer to a repair shop or parts seller, so the module should be identified by part number before anyone forms a theory.

Inflator Rupture

The Takata recalls are the best-known example of a bag that deploys and injures. NHTSA reports that tens of millions of vehicles with Takata air bags are under recall, and that long-term exposure to high heat and humidity can cause these air bags to explode when deployed, with injuries and deaths as the result ⁴. Do Not Drive warnings have been issued for some vehicles ⁴. A separate group of Takata inflators, of a non-azide driver design, was recalled in late 2019 ⁴. These cases need preservation first. Metal fragments, the inflator housing and the recall and repair history of the vehicle are the core evidence, and NHTSA's recall page includes preservation orders and testing protocols that show how seriously that evidence is treated ⁴.

Deployment Injury and Occupant Position

A properly working bag can still injure someone who is too close. NHTSA still recommends keeping a 10-inch minimum between the air bag cover and the breastbone, even with advanced frontal air bags ¹. Disputes follow about seating position, height, belt use, and whether a child was in the front seat. A biomechanical engineer ties the injury pattern to the bag rather than to the crash, which can be hard because the two happen within moments of one another.

Preemption

Design claims can meet a federal defense. In Geier v. American Honda, the Supreme Court held that a no-airbag lawsuit conflicted with the objectives of FMVSS 208 and was pre-empted ⁵. The Court also read the saving clause to mean that compliance with a federal standard does not exempt a party from all common-law liability, and held that the Act's express pre-emption clause did not itself bar the suit ⁵. Williamson v. Mazda then held that FMVSS 208 did not pre-empt a claim that a manufacturer should have installed lap-and-shoulder belts instead of lap belts on rear inner seats ⁶. So the question is narrower than whether the standard applies. Counsel should ask whether the claim would conflict with a choice the regulation meant to preserve. A claim that a deployed system malfunctioned is a different kind of claim from one that a system should have been fitted.

Who Is Qualified, and Who Does What

No license is specific to this field. Strong witnesses include automotive engineers with direct experience in restraint system design, testing, or sensor calibration. Match each role to its question. A restraints engineer addresses the system and its logic. An accident reconstructionist establishes crash severity and direction. A biomechanical engineer addresses injury causation. A materials or failure analysis expert examines an inflator rupture. An EDR analyst reports what the module stored.

Qualifications

Qualifications to Look For

• ✓Automotive engineering background with direct experience in restraint system design, testing, or calibration
• ✓Working command of FMVSS 208 and its test conditions
• ✓Experience reading air bag control module and event data recorder reports
• ✓Ability to inspect inflators, modules, sensors, and wiring without altering evidence
• ✓Knowledge of recall records and NHTSA defect investigations
• ✓Experience working with reconstruction and biomechanical experts
• ✓Prior deposition and trial testimony experience in crashworthiness cases

FAQ

Frequently Asked Questions