Would you let someone smack you in the head with a gallon of milk? No really. Let's say they were able to swing the gallon of milk at about 25 miles per hour. Would you let them hit you in the head with it? I know it's a dumb question, and I know what you might be thinking. No, it doesn't matter if it's 2% or Skim.
A gallon of milk weighs 8.6 pounds. Traveling at 25 miles per hour, it would hit your head with an average impact of 1,369 pounds of force. This is enough force to cause severe injury or death. Okay, so what does that mean?
Let me put it this way. Mike Tyson, who is often considered to have had the most powerful punch of all professional boxers, punched with about 1,167 pounds of force. His punch would destroy other heavyweight boxers who spent their lives learning to take a punch.
The average head weighs 11 pounds. Traveling at 25 miles per hour, your unrestrained head (meaning you are not wearing a seatbelt) would have an impact force of 1751 pounds.
Crash! Boom! Bang! Not Good.
So let's say you are 150 lbs (yeah, I haven't been that weight since Jr High) at 25 miles per hour with no seat belt. The impact is equal to 23,881 pounds of force. Imagine laying on the ground and being pressed with 23,800 lbs. That's what it feels like.
Remember, 25 is the slow speed in neighborhoods and most school zones.
The highest speed on our non-interstate roadways within the city limits of Missoula is 45 MPH. Again, assuming that you weigh 150 lbs, at 45, the crash impact force of your body hitting other people, the steering wheel, the windshield, or other parts of the passenger compartment of a vehicle is now 77,375 pounds of force. Wow!
200 lbs at 45 miles per hour with no seat belt, the impact force is 103,166 lbf.
Want to play around with the numbers and learn more about how seatbelts reduce the impact force you experience by spreading it out over time? It's fun and exciting. Give it a go.