Nearly 840,000 blind spot collisions occur in the U.S. annually resulting in approximately 300 fatalities, according to the National Highway Traffic Safety Administration.

The government agency notes that these accidents are partly die to drivers not properly adjusting their mirrors, or not properly checking their blind spots when changing lanes.

Blind spots are anything that isn't visible in the rear view or two side mirrors.

While commercial drivers log more miles than the average driver and often have years of experience on the road, this very fact can sometimes lead to complacency. It's easy to get lazy and fall into bad habits. Add to that the fact that many of today's vehicles are equipped with back-up cameras, giving drivers a false sense of security. Together, these issues can lead to drivers' failing to properly check for blind spots.

All fleet drivers should be reminded that when checking one's side mirrors, there will be a blind spot in both the back right corner and the back left corner.

Simply put, experts say the best way to avoid a blind-spot collision is for the driver to check over his or her shoulder before changing lanes. This applies to both right and left lane changes. A quick turn of the head with a focus on the roadway behind compensates, allowing the driver to capture with his own eyes what the mirror fails to show.