How Serious Does a Collision Have To Be for Airbags To Deploy?

Understanding how severe a collision has to be for airbags to deploy helps drivers know what to expect after an accident. Airbags are designed to deploy only in moderate-to-severe car crashes, where occupants face a significant risk of injury.

Speed Thresholds for Airbag Deployment

Frontal airbags typically deploy in collisions when a vehicle hits a solid object at about 12 to 14 miles per hour. Airbag systems may deploy at slightly lower speeds for occupants who are not wearing seatbelts, since unrestrained passengers face a higher risk of injury.

This speed range serves as a general guideline rather than an absolute rule. The actual deployment depends on how hard the impact was, not just travel speed. A crash into a parked car creates different forces than a head-on collision with another moving vehicle, even at identical speeds.

How Crash Sensors Determine Deployment

Airbag systems decide whether to deploy by measuring how quickly a vehicle slows down and how severe the impact is. The process follows a few basic steps:

• Sensors detect sudden deceleration: Crash sensors register rapid changes in speed that indicate a collision and measure how strong the impact is.
• The system analyzes crash data: Information from multiple sensors is sent to the airbag control module, which evaluates the force and direction of the crash.
• Safety checks confirm deployment: Safing sensors verify the data to ensure the impact meets specific thresholds before airbags are activated.

By requiring both sufficient force and confirmation from multiple sensors, the system reduces the risk of unnecessary deployment while still responding quickly in serious crashes.

Types of Airbags and Their Deployment Criteria

Vehicles are equipped with different types of airbags, each designed to deploy in specific crash situations based on impact direction and severity, as follows:

• Frontal airbags: These airbags deploy in moderate to severe head-on crashes to protect the head and chest from striking the steering wheel or dashboard.
• Side airbags: Side airbags activate during side-impact collisions, including T-bone crashes. In narrow-object impacts, such as hitting a pole, they may deploy at relatively low speeds.
• Curtain airbags: Curtain airbags deploy from the roofline during severe side impacts or rollover accidents to help protect the head.
• Knee airbags: Located beneath the steering wheel, knee airbags deploy in frontal crashes to reduce lower-body injuries and help control occupant movement.

Each airbag type uses its own sensors and deployment thresholds, allowing the system to respond appropriately based on the specific nature of the crash.

Why Airbags Sometimes Don’t Deploy

Airbags are designed to deploy only when they provide meaningful protection. In certain situations, the system may determine that deployment is unnecessary or ineffective. These situations include:

• Low-speed collisions: Impacts below specific force thresholds may not trigger airbags because seatbelts alone are considered sufficient protection.
• System defects or prior damage: Faulty sensors, wiring issues, or a malfunctioning control module can prevent airbags from deploying. Previous accident damage may also interfere with sensor performance.
• Rear-end collisions: Frontal airbags typically do not deploy in rear-end crashes because the force pushes occupants backward into their seats, making frontal airbags ineffective.

In most cases, non-deployment reflects how airbag systems are engineered to function. When airbags fail to deploy in serious crashes, it may indicate a defect or mechanical issue that requires closer evaluation.

The Role of Airbags in Personal Injury Claims

When airbags deploy, it is evidence that the crash was strong enough to trigger the system, which can help prove how serious the impact was. This can support an injury claim by giving solid evidence of the collision’s force.

Insurance companies may argue that if the airbags did not deploy, the crash must have been minor. However, there are several genuine reasons why airbags might not deploy in a serious crash, including a defective airbag system, the angle of the impact, or the type of collision.

Always document your injuries right away, even if the airbags did not deploy. Some injuries, especially soft tissue injuries and concussions, often do not show symptoms until hours or even days after the crash.

Safety Considerations and Best Practices

Airbags are most effective when combined with proper safety habits and regular vehicle maintenance. Following these best practices can help reduce injury risk and ensure the system works as intended:

• Wear your seatbelt correctly
• Maintain proper seating position
• Keep airbag areas clear
• Inspect the system after collisions

Airbag deployment depends on complex engineering calculations rather than simple speed thresholds.

A Seattle Car Accident Lawyer Can Help

Airbag deployment, or the lack of it, can raise important questions after a serious crash. Whether airbags deployed as expected or failed to activate, the details of how the collision occurred can affect both injury claims and liability in Washington state. 

If you’ve been injured in Seattle, WA, and need legal assistance, contact Davis Law Group Car Accident and Personal Injury Lawyers. Contact our legal team and schedule a free consultation with a [PRACTICE AREA] lawyer today. We proudly serve King County in Washington and its surrounding areas. Visit our law office at:

Davis Law Group Car Accident and Personal Injury Lawyers
2101 4th Ave 1030 Seattle, WA 98121
(206) 727 4000
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