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Here’s the proper way to use your emergency flashers

Traffic is bumper to bumper on the Capital Beltway near National Harbor on Wednesday night. If you’re going with the flow — no matter how slow — consider whether you really need to declare a personal emergency. (Alex Brandon/AP)

With all the wind and snow coming this weekend, it’s going to be difficult for anyone unfortunate enough to be driving to stay focused.

If you must drive, please consider when and where it’s appropriate to use your four-way emergency flashers. Some drivers who are moving along with the flow of traffic are a little too quick to declare a personal emergency.

The laws on hazard lights vary from state to state, but common sense says that when you put them on, you are declaring that you are a hazard to other motorists. They are meant to be used when you have an emergency.

The fact that you chose to go out in snow and high wind does not constitute an emergency, unless your driving turns it into one.

We’ve discussed this topic before in my column. One scenario that many drivers cite makes sense to me: There’s a blockage up ahead, and you’re the last car stopped in a highway lane. The cars behind you are approaching at highway speed and might not be aware of the hazard. The flashers can serve as a warning to those drivers.

But I can’t think of any good reason to use emergency flashers if you’re driving in the same conditions and about the same speed as everyone else. Because the flashers are so commonly used to warn of a vehicle stopped by the roadside, using them while driving might confuse other drivers and create a fresh hazard.

An inch of snow caused a traffic standstill in parts of Washington, D.C., on Jan. 20. Slick roads led to more than 100 traffic accidents. (Video: Reuters)

Safety experts have noted that drivers have an unconscious tendency to turn the steering wheel in the direction they’re looking. If their eyes are following the flashing lights, their steering wheels may do the same. People shouldn’t do that, but it happens.

That’s the highway scenario. But  more bothersome examples occur on local streets, where drivers can make turns. On most car models, pushing the button for the emergency flashers activates all the turn signals. (With some drivers, that’s the only time they ever activate their turn signals, but that’s another discussion.) Flipping on a turn signal doesn’t deactivate these emergency flashers. They’re still what other drivers see as you prepare to make a left or right turn. They’re also what pedestrians at the intersection see, so they have no idea you’re about to turn across their path.

So if you’re going to use emergency flashers, let it be for an emergency. And if it’s an emergency, get out of the travel lanes as quickly and safely as possible. Otherwise, rely on your headlights and tail lights to provide visibility to other travelers. And leave the emergency flashers for the big, slow-moving plow trucks. There will be plenty of them around this weekend.