ST PETERSBURG, Fla. - Why can't people hear a train coming from behind them?

Modern trains are built to be quiet and travel as smoothly as possible. Forests and other terrain can also help make the trains quieter as they pass through an area.

But what about the train's horn?

Lucas Fidler, owner of Audio Expert in Clearwater, says two main factors impact one's ability to hear a train and it's horn - headphones and not facing the train, for human ears are trained to get sound from the front and side.

“But when you wear headphones, at a regular range like 80 decibels, and you are walking away from the train that's blaring the horn about 50 feet away you still are likely unable to hear it,” Fidler said.

Yazmin White, 11, of Haines City, was killed on Wednesday after she was hit and killed by an Amtrak train while she was looking down at her phone and listening to headphones.

A few weeks prior, Brenda Salyers, 60, of Lakeland, was hit and killed by an Amtrak train.

While a locomotive train is about 90-95 decibels loud, it's horn can reach up to 140 decibels, Fidler said.

“While you may think you would hear that train coming, don't assume you will, you need to understand how the ear hears sound and what distractions you are experiencing at the time,” he said.

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