When automobiles are involved in highway accidents with semi- trucks, those traveling in the automobiles are generally at far greater risk and danger than those traveling in the semi-trucks. It is really just a matter of physics. The mass and kinetic energy of a loaded semi truck traveling at 55 miles per hour is almost always significantly greater than the mass and kinetic energy of any automobiles on the road. Just as the energy, mass and force of a person’s foot can collapse an aluminum beverage can with little or no damage to the foot, automobiles are often crushed and severely deformed when they collide with the formidable mass of a loaded semi-truck.
It is for these very reasons that semi-trucks are often required to travel at slower highway speeds than the automobiles on the road. It is also because the potential for serious damage, injury and death is greater in automobile accidents involving semi-trucks than it is when only automobiles are involved, that licensed semi-truck drivers are required by law to pass skill and training tests that are more comprehensive and difficult than the tests required to obtain an automobile driver’s license. Additionally, semi-truck drivers are generally required by law to carry greater wrongful death and injury insurance (often in amounts exceeding $1,000.000.00) than are automobile drivers. In the United States alone, over 5,000 people die each year in truck accidents. http://transit-safety.volpe.dot.gov/Safety/Safety.asp