When Should You Use Emergency Flashers?

Use Emergency Flashers to Warn Others

You should turn on emergency flashers or hazard lights only when you need to warn other drivers of an emergency or a traffic hazard.

But what is an emergency or hazard? When is it OK to turn on emergency flashers? When is it NOT OK?

You will get different answers depending on who you ask. It is not easy to answer since the law differs between states. Common practice is also different.

When Your Vehicle Breaks Down

If your vehicle breaks down and you must stop in a hazardous location where your car may interfere with other traffic, you should always turn on your emergency flashers.

If you can move your vehicle and stop on the shoulder of a highway, you should also use your emergency flashers. Flashers will warn other drivers and give them time to slow down and move to another lane, if possible.

When Pulled over by Police

If a law enforcement officer signals you to stop and pull over, rules may recommend you turn on the emergency flasher and pull off the roadway. Your lights show the officer that you acknowledge his signals. They will also warn other drivers. The officer will allow you to keep driving with your emergency flashers engaged for a short distance until you reach a haven or well-lit area at night.

It is, however, usually enough to engage your turn signal and pull over.

When There is an Unexpected Emergency

You can use emergency flashers to warn other drivers of a real and unexpected emergency. Such a recommendation applies when there is a hazardous obstacle on the roadway, a sudden and severe problem with your vehicle, or any sudden health problem that affects your driving.

Be careful not to use emergency flashers if you must slow down and exit the highway because of an unexpected problem. Turn signals are normally disabled when you turn on the flashers. It can be challenging for others to understand your intentions, which could result in a crash.

Stationary Vehicles

Always use emergency flashers when you have stopped because of an emergency and where it may be hard for other drivers to see you. It is vital when you have stopped closed to travel lanes.

It does not mean that you should turn on emergency flashers every time you plan to stop.

It is common to see drivers obstructing traffic by stopping unnecessarily on a roadway to wait for someone or loading or unloading passengers. Turning on emergency flashers does not make such a stop safe or legal. It is better to keep driving until you can stop in a location where you don’t obstruct traffic.

How about turning on emergency flashers when you double park for a quick errand?

The same rule applies here; flashers don’t make double parking legal.

Bad Weather

In general, you should turn on emergency flashers on a stationary vehicle and not drive with hazard lights on, not even in bad weather. If your vision ahead is limited, turn on low-beam headlights and slow down. Should the road ahead become barely visible, your best action is to pull off the roadway and wait until conditions improve. Park as far as possible from the travel lane. When you have stopped off the road, turn on your flashers.

Remember, driving with emergency flashers on may be illegal in your state – regardless of your reason for using them. But more importantly, some drivers will not expect to see hazard lights on a moving vehicle. If they think you have stopped by the side of the road and it is hard to see the edge, they may move to the left to avoid you and end up in an opposing lane.

Slow Driving

Most state laws allow truck, bus, or tractor-trailer drivers to use hazard lights when going up a steep hill or under other conditions when the vehicle cannot keep up with the traffic flow. The driver of a car may not have the same privilege.

Impeding traffic by driving too slow is generally against the law in all states. If you, for a reason other than an emergency, must go slower than the traffic flow, you should find another route with a lower speed limit. Your emergency lamps are never an excuse for dangerous or illegal driving.

Funeral Processions

Funeral processions are an exception to these rules. Vehicles in a funeral procession may drive with active hazard lights, even if the law otherwise prohibits driving with activated flashers.

Rules in Your State

Driving with Active Hazards Lights Prohibited

• Alaska
• Arizona (except in an emergency)
• California (except to indicate a traffic hazard)
• Colorado (except if the vehicle speed is 25 mph or less)
• Delaware (except to indicate a traffic hazard)
• Florida
• Hawaii
• Idaho (except to indicate a traffic hazard)
• Illinois
• Indiana (except in an emergency)
• Iowa (except to indicate a traffic hazard)
• Kansas
• Louisiana
• Maine (except to indicate a traffic hazard)
• Maryland (except in an emergency)
• Massachusetts
• Minnesota (except to indicate a traffic hazard)
• Montana (except to indicate a traffic hazard)
• Nevada
• New Mexico
• Ohio (except when a hazardous condition is present)
• Oklahoma (except in emergency situations and to indicate a traffic hazard)
• Rhode Island
• South Carolina (except to indicate a traffic hazard)
• Tennessee (except in emergency situations)
• Virginia (except to indicate a traffic hazard or when traveling slower than 30 mph)
• Washington (except to indicate a traffic hazard)
• West Virginia (except in emergency situations)
• Wisconsin (except to indicate a traffic hazard or when a hazardous condition is present)

Driving with Active Hazards Lights Allowed,

• Alabama (unless otherwise posted)
• Connecticut (unless otherwise posted)
• District of Columbia
• Georgia
• Kentucky
• Michigan
• Mississippi
• Missouri
• Nebraska
• New Hampshire
• New Jersey
• New York (unless otherwise posted)
• North Carolina (unless otherwise posted)
• North Dakota (unless otherwise posted)
• Oregon (unless otherwise posted)
• Pennsylvania
• South Dakota
• Texas
• Utah
• Vermont
• Wyoming

DMV Test Questions for Your State