FMVSS 214: Side Impact Tests, Barriers, and Injury Limits

FMVSS 214 is the federal side impact protection standard set by the National Highway Traffic Safety Administration, and it requires passenger cars, SUVs, minivans, trucks, and buses with a gross vehicle weight rating of 10,000 pounds or less to pass a static door crush test plus one or two dynamic crash tests, all while keeping injury measurements on instrumented crash-test dummies below specified thresholds. Doors have to resist being pushed inward. Dummies inside cannot record forces above the levels that correlate with survivable injuries. Everything else in the standard flows from those two ideas.

Which Vehicles Have To Comply

The standard covers passenger cars, multipurpose passenger vehicles like SUVs and minivans, trucks designed to carry at least one person, and buses with a GVWR of 4,536 kilograms (10,000 pounds) or less, excluding walk-in vans.¹ Not every vehicle in that range faces the same tests. Requirements split into three tiers:

Passenger cars, at any weight, must pass the static door crush resistance test, the moving deformable barrier (MDB) crash test, and the vehicle-to-pole test.
MPVs, trucks, and buses at or below 6,000 pounds GVWR face the same three tests.
MPVs, trucks, and buses above 6,000 pounds GVWR must pass the door crush test and the pole test, but are exempt from the MDB crash test.

The 6,000-pound line matters. A heavy-duty pickup or full-size SUV above that threshold still needs side curtain airbags and a door structure that can survive a pole strike, but it won’t face the simulated intersection crash that lighter vehicles must handle.¹

Static Door Crush Resistance

Before any dynamic testing, every covered vehicle must prove its side doors can resist being pushed inward. This is the oldest part of the standard and applies across the full 10,000-pound GVWR range. Manufacturers pick between two testing options.¹

With seats removed, the door must withstand an initial crush force of at least 2,250 pounds, an intermediate force of at least 3,500 pounds, and a peak force equal to double the vehicle’s curb weight or 7,000 pounds, whichever is less. With seats installed, the initial threshold stays at 2,250 pounds, the intermediate requirement rises to 4,375 pounds, and the peak requirement jumps to three-and-a-half times the curb weight or 12,000 pounds, whichever is less. The seats-installed option demands higher resistance because the seat structure absorbs some of the crash energy that would otherwise reach the dummy.

The Moving Deformable Barrier Test

The MDB test simulates a broadside intersection collision. A 3,000-pound barrier cart with a crushable aluminum face is driven into the side of the stationary test vehicle at 33.5 miles per hour (53.9 km/h). The cart’s wheels are angled 27 degrees toward the rear of the target vehicle so that at the moment of impact the barrier face strikes parallel to the vehicle’s side, replicating a 90-degree crash where the striking car is going about 30 mph and the target vehicle about 15 mph.¹

Two instrumented dummies ride the struck side. The front outboard seat gets a 50th-percentile male ES-2re dummy, representing an average-sized adult man. The rear outboard seat gets a 5th-percentile female SID-IIs dummy, representing a smaller adult woman. Sensors record chest deflection, abdominal force, pelvic loading, head acceleration, and spine response throughout the impact.

The Vehicle-to-Pole Test

The pole test addresses a different and often deadlier crash: a vehicle sliding sideways into a narrow rigid object like a tree or utility pole. Force concentrates on a small area instead of spreading across the door panel, so intrusion is severe and head-injury risk is high even at moderate speeds.

The vehicle is propelled sideways at up to 20 mph (32 km/h) into a fixed rigid pole 10 inches in diameter. The vehicle’s path forms a 75-degree angle with its own longitudinal centerline, producing an oblique strike rather than a perfectly perpendicular one. NHTSA chooses which dummy sits in the front struck-side seat: either the ES-2re 50th-percentile male or the SID-IIs 5th-percentile female.¹ Meeting the head-injury limit in this test is essentially impossible without a side curtain airbag covering both front and rear windows, which is why curtain airbags are now standard equipment across the industry.

Injury Thresholds The Dummies Cannot Exceed

Passing the MDB and pole tests comes down to whether the forces recorded on the dummies stay under set limits. The limits depend on which dummy is being used.

ES-2re (50th-Percentile Male)

Used in the front seat during the MDB test and in either configuration during the pole test.¹

Head Injury Criterion (HIC): 1,000 maximum.
Chest rib deflection: no individual rib (upper, middle, or lower) may deflect more than 44 millimeters (1.73 inches).
Abdominal force: combined force across the front, middle, and rear abdominal sensors must stay below 2,500 newtons (562 pounds).
Pubic symphysis force: pelvic loading capped at 6,000 newtons (1,350 pounds).

SID-IIs (5th-Percentile Female)

Used in the rear seat during the MDB test and in either configuration during the pole test.¹

Head Injury Criterion (HIC): 1,000 maximum.
Lower spine acceleration: resultant acceleration at the lower spine capped at 82 g.
Pelvic forces: combined acetabular and iliac pelvic forces must stay below 5,525 newtons (about 1,242 pounds).

Compliance Is Not The Same As A Five-Star Rating

Passing FMVSS 214 is the legal minimum. NHTSA’s New Car Assessment Program, which produces the familiar five-star safety ratings, runs its own side impact test using the same MDB configuration but at 38.5 mph instead of the regulatory 33.5 mph.² That higher speed separates vehicles that barely meet the standard from vehicles with genuinely strong side protection. A vehicle can comply with FMVSS 214 and still earn a mediocre NCAP star score, so a shopper looking for the safest option should check both.

What Happens If A Vehicle Fails

NHTSA has authority to require a recall of any vehicle that does not meet a Federal Motor Vehicle Safety Standard.³ The manufacturer must notify NHTSA, owners, dealers, and distributors of the deficiency and then repair the problem at no cost to the owner, with NHTSA monitoring the campaign to verify the work is done.

Civil penalties can reach $27,874 per individual violation, and each noncompliant vehicle counts as a separate violation. For a related series of violations the maximum caps at roughly $139.4 million.⁴ For a manufacturer moving hundreds of thousands of units, a systemic FMVSS 214 failure means recall costs in the hundreds of millions on top of the civil penalty.

The May 2025 Proposed Cleanup

In May 2025, NHTSA proposed a rule to remove obsolete provisions from FMVSS 214, including legacy MDB test procedures that used older SID dummies with lower injury-measurement capability. Several sections that applied only during the original phase-in period would be removed and reserved.⁵ The performance requirements and injury thresholds described above would not change. It is a housekeeping measure, not a tightening of the standard.

1
eCFR. 49 CFR 571.214 – Standard No. 214; Side Impact Protection
2
National Highway Traffic Safety Administration. Evaluation of FMVSS 214 Side Impact Protection Dynamic Performance Requirements
3
National Highway Traffic Safety Administration. Motor Vehicle Safety Defects And Recalls
4
eCFR. 49 CFR Part 578 – Civil and Criminal Penalties
5
Federal Register. Federal Motor Vehicle Safety Standards No. 214, Side Impact Protection