Semi truck accidents lead to more fatalities than any other auto accident. Due to their large size and weight, semi trucks can cause whiplash damage even in low speed accidents at only five miles per hour. Most deaths that occur in these accidents happen to the passengers of the other vehicles involved. Semi trucks are built dangerously, having large blind spots and very poor reaction performance during emergency situations. Semis also can be improperly loaded which cause further danger on the road when the load is unbalanced or overweight. And a semi's most normal road malfunction deals with tires issues, which can easily cause an accident. Additionally, semi trucks can experience total brake failure, especially on steep grades and fast descents. Of course, driver's error plays a key role in semi truck accidents, but most errors are not the fault of the semi driver. Only four percent of semi crashes occur due to driver's fatigue, and only one percent are caused by a semi driver driving drunk. Normally, speeding and negligence by other drivers lead to semi truck accidents.