Icy bridges, a winter weather hazard that's often underestimated, cause more injuries and fatalities than tornadoes, lighting and floods combined each year.

Slick, slippery bridge surfaces often come as a surprise as ice on a bridge may be invisible to the driver. Because vehicles can hit the icy bridge surface without warning, accidents frequently happen at full highway speed — making them particularly dangerous.

In order to avoid crashes and stay safe while crossing bridges this winter, fleet drivers should keep the following in mind:

• Stay aware of the weather: Always listen to the reports in your area and if your route covers a lot of distance, make sure to check the weather for your planned destination in advance.

• Understand the difference between sand and salt: If you live in a region that uses sand versus salt on roads and bridges, it is all the more important to drive with caution. Sanded bridges are likely to be slicker because sand does not melt ice.

• Know the warning signs of an icy bridge: Any precipitation when temperatures are near or below freezing could cause ice to form on a bridge. In addition, if ice is forming on your mirrors and windshield, chances are it is forming on any bridges you approach as well.

• Reduce your speed: When approaching an icy bridge, slow down; moving at a higher speed means you are more likely to hit a patch of ice and lose control.

• Avoid braking, changing lanes, or accelerating on the bridge: If the bridge is icy, any sudden moves can make your vehicle slip, slide and spin.

If you do slide or have an accident on an icy bridge, follow these steps:

• Turn into the slide: Don't panic and gently turn into the slide to regain control of your vehicle.

• Be aware of other vehicles: If you hit an ice patch on a bridge, chances are good that other vehicles will, too, so stay aware of what is happening around you.

• Never exit your vehicle on an icy bridge: Leaving the vehicle leaves you open to being hit by another vehicle. Stay put and try to move your vehicle out of the way of traffic.