Lac-Megantic Train Wreck-July 6, 2013
Firefighters look at a train car on fire at Lac-Megantic, a town of about 6,000 people in the province of Quebec. Reuters

Brake failures lead to serious railroad accidents that are caused by human error or faulty systems, the Wall Street Journal reports Tuesday.

Brake-related accidents have totaled around $4.1 million in damages in 2012 and around $90 million over the past 10 years.

Just recently the train derailment in Quebec that killed 50 people was caused by an employee not setting the brakes properly, according to the train company.

In 2012 the industry had the safest year, Holly Arthur, a spokeswoman for the Association of American Railroads, said. This was despite being the busiest year for the shipment of crude oil.

"It is still premature to speculate about how and if this accident [in Quebec] could influence future regulations or changes to railroad operating procedures," Arthur said.

While there has been a decline in brake-related accidents, they still amount to some of the most serious train accidents. However, another common cause of train accidents in the U.S. are what’s called switching maneuvers, where railcars connect or disconnect from each other, and in 2012 such incidents accounted for 13 percent of all freight train accidents.