Understanding the Three Collision Rule

Motor vehicle crashes involve three types of collisions: vehicle collision, human collision, and internal collision. Being aware of the three collisions concept and understanding the dangers allows occupants to understand where and how their injuries occur.

When you first see an auto accident take each car and multiply it by three. With every vehicular accident, there are three collisions that happen within each car. This is known as the three- collision rule. When learning about the three rules it is important to have a clear understanding of kinetic energy. Kinetic energy is the energy built up in a moving object. When an accident occurs, the kinetic energy from one car will transfer to the object it encounters. There are three collisions that happen within a vehicle accident.

A car accident problem is one of the first things studied in a physics class when learning about Newton’s Laws of Motion. It is the governing science for collision theory. The laws state that a body in motion will remain in motion until there is an equal but opposite force to all static situations, and force is equal to the mass of the object times its acceleration. This is true for each and every object inside of a vehicle – including humans and their organs. Understanding the 3 types of collisions after a car crash can help understand how you can be injured in a crash.

What are the 3 stages of a collision?

Stage 1: Vehicular Collision

The first stage is known as a vehicle collision. This occurs when the vehicle strikes another object and is most closely associated with a car crash.

As the car collides with another object, it begins to crumple and slow down. The ability of the vehicle to crumple is important, as it takes away some of the energy of the crash, thus helping to protect the people inside. Therefore, specific crumple zones are intentionally designed into every automobile for this purpose.

An entire vehicle collision – from the initial contact with another object to full stop – occurs quickly. For instance, a vehicle traveling 30 MPH will experience the entire process in about one-tenth of a second.

While that isn’t a whole lot of time to react, there are some things you can do to lessen both the impact of the collision and personal injury. If you’re ever experiencing a situation with an oncoming crash, try to veer into an object that can absorb some of the energy, like a bush.

It is important to remember, though, that while this is taking place, the two other stages of a collision are just beginning.

Three clues give away how fast the vehicle was going when it hit impact. The first one is the posted speed limit in that area. Second, skid marks or other indications of attempts to slow the vehicle down before the collision. Lastly, how the vehicle looked after the car crash. Modern cars are designed to crush easily to absorb most of the kinetic energy before it reaches the individual inside.

Property damage is always a major factor when insurance companies value a claim. It tells a major part of the story when evaluating how injured the persons inside the vehicle are. But other factors are at play as well, such as make and model of the vehicle, and whether the impacted vehicle as a trailer hitch, which can potentially increase the injury to the individual inside.

Stage 2: Human Collision

In the initial moments of a collision – when the vehicle begins to crumple and slow down – its occupants are still moving at their normal speed and direction. This continues until the occupants come in contact with an object that causes their forward motion to stop.

It is during this second stage that we see the importance of property equipped seatbelts and airbags. Think of a moment where you had to quickly stop on the brakes – maybe to avoid that deer or stop for a child chasing after their soccer ball. You may have been jerked forward ever so slightly, but thanks to your seatbelt, your body was prevented from going any farther.

Specifically, an unrestrained person involved in a 30 MPH collision will slow from 30 MPH to a stop in just a few hundredths of a second – with only his or her body to absorb all the energy of the impact. Depending on the severity of the collision, this could cause a person to be propelled forward and into the windshield. A person wearing a seatbelt, on the other hand, will come to a stop more gradually, as the seatbelt absorbs some of the energy from the impact.

During the second stage of “human collision,” all occupants in the vehicle will still be moving in the same direction and speed as they were before the collision happened. Inertia will keep the occupants moving toward the point of an impact unless a seatbelt or airbag stops them. However, if an occupant is unrestrained, occupants can be hurled forward and stopped by some part of the vehicle, such as a steering wheel, window, or the dashboard.

Occupants in a crash can also collide with each other and can sustain devastating injuries. For example, people in the front seat of a car can be hit by passengers in the backseat as they are forcefully thrown forward. Loose objects inside the vehicle can also cause a serious injury from the force of the collision. For example, a cell phone or laptop can cause severe injury after colliding with an occupant.

Stage 3: Internal Collision

As the vehicle and occupants slow down, the organs and body tissues inside a person will still be moving towards the point of impact. Again, inertia will continue to move organs and body tissue at this last stage. Internal organs will continue to move until they are stopped by hitting other organs, bones, or the skull. Internal organs such as the brain being moved against the skull can cause a serious traumatic brain injury.

Although someone involved in an auto crash may at first appear uninjured, he or she might have sustained internal injuries resulting from this third collision. The liver, heart, spleen, or another organ can become bruised from impacting each other or other surfaces within the body. Accidents that are involved in high deceleration forces can cause one’s solid organs to bleed, rupture, fracture, and tear. The brain can be bruised from hitting the inside of the skull, too. Proper restraint within a vehicle will help to prevent these types of serious injuries.

This is why it is crucial you seek the guidance of an experienced auto accident attorney who is very familiar with the three-collision concept. Call the Law Offices of Larry B. Litt today.

How to reduce the risk of an injury during a collision

When you get in your car, the last thing on your mind is getting into a car crash. However, staying prepared can reduce the risk of a severe or fatal injury should you be involved in a collision. Here are some tips on how to keep your car crash-ready and your passengers as safe as possible.

  • Buckle up – Seatbelts save lives! Both drivers and passengers should stay buckled up during the entire trip – even if you are sitting in the back seat. It’s also essential to ensure that your seatbelt is fastened correctly (keep the lap belt front lying across your belly). This could cause serious internal injuries in the event of an accident. Wear your lap belt tight and low over your pelvic bones. Also, do not wear the shoulder belt on the neck or collar bone or under your arm as this could cause serious lacerations or bone fractures. The shoulder belt should pass over the middle of your shoulder.
  • Don’t sit too close to the steering wheel – Sitting too close to the steering wheel can cause fractures to the rib and soft tissue injuries. Sitting too close to the steering wheel can also cause harm from the airbag deployment to your face, neck and chest.
  • When driving, keep your seat positioned correctly – An incorrectly set seat can increase the risk of leg, back, and whiplash injuries. Keep your seat positioned close enough to the pedals, so you don’t have to extend your leg fully. In the event of a car wreck, having your legs bent can help absorb impact from the accident and reduce the risk of fractures and injuries to your lower back.
  • Keep children in car seats – Keep your child in a car seat or booster seat. Choosing the right car seat depends on their age, height, and weight. Never place a rear-facing infant seat in the front seat. Booster seats and other car seats should also be kept in the back seat of the car. Children under 13 years of age should always ride in the back seat, and whenever possible, in the middle of the backseat with seatbelts fastened. If you are unsure about the type of car seat you should use your child’s Pediatrician can help you find a car seat finder tool that is easy to use.
  • Keep loose items in the trunk – Any object, such as a laptop or cell phone, can cause a severe injury in a car wreck. The safest place for any item in your car is the trunk. If you must carry something inside the vehicle, keep it on the floor behind the driver or passenger seat.

What to do after a collision

Even if you think you have not been injured or you “feel fine,” seek medical attention immediately. Many injuries can go undetected for hours or even days. Failing to care for an injury, such as a traumatic brain injury, including concussions, could have long-term devastating effects. Here are some common delayed symptoms after a car collision that shouldn’t be ignored:

  • Headaches
  • Stiffness in the shoulder and neck
  • Nausea/vomiting
  • Fatigue
  • Blurred vision
  • Confusion
  • Forgetfulness
  • Back pain
  • Abdominal pain
  • Ruptured spleen
  • Internal bleeding
  • Numbness or tingling, shooting pain
  • Trouble sleeping
  • Depressed moods


Involved in a car crash? We can help.

I have had clients needing shoulder surgery due to a rear-end car crash on their vehicle with a trailer hitch. It can pin-point the force and intensify it for the person inside. You will need an experienced lawyer to advocate for you in these instances against the insurance company.

Sustaining an injury in a car accident can be devastating and have lifelong effects on the victim and their families. If you’ve been hurt in a car accident, we can help. When it comes to handling the insurance companies, we will guide you every step of the way from recovering medical costs, lost income, property damage, and more – we’ll be your trusted attorneys throughout the process. We are here for you 24/7. Please call the Law Offices of Larry B. Litt today at 443-844-1528, we have decades of experience with the three stages of a collision.