By Nnamdi Ikeh-Akabogu (FRSCN)
Hazard warning lights are a pair of intermittent flashing indicator lights that flash in unison to warn other drivers that the vehicle is a temporary obstruction.
They are also called hazard flashers and hazard lights. Different countries use hazard warning lights in different ways.
In New Zealand they wouldn’t be used on a motorway to warn other drivers that we’re slowing down, but in the UK, this is recommended.
They are usually activated by pressing a button on the dashboard that looks like a red triangle, as shown. Some vehicles will automatically activate the hazard warning lights under heavy braking or if the vehicle is involved in an accident.
When should you use hazard warning lights?
- They are to warn other road users that you are a temporary hazard. For example, if you have broken down on the side of the road, or you are changing a tyre. If you are being towed, you should use your hazard warning lights.
- If you are being towed and you are using your hazard lights, you will need to use hand signals to indicate direction because the hazard lights override the indicators.
- Getting pulled over. If law enforcement signals you to pull over, turning on your hazard lights can show the officer that you acknowledge their signal and are following the request. Slow down, turn on your hazard lights, and stop your car in a safe location.
- Changing a tire on the side of the road. Use your hazard lights when your vehicle becomes a potential hazard for other road users. If you’re parked on the side of the road changing a tire, it’s generally okay to have your hazards on.
- Your car has broken down and you’re waiting for a tow. Your car has become a temporary hazard and you’re waiting for assistance. Warn other drivers of your presence, especially if you are not able to move your car out of traffic.
- Driving in a funeral procession. Funeral processions are an exception to most hazard light guidelines. It’s customary for vehicles in a funeral procession to drive with their hazard lights on, even when it is otherwise prohibited by law.
When should you not use hazard warning lights?
- They shouldn’t be used if you are driving in traffic. You should not use them to warn other drivers if you parked illegally (you shouldn’t be parking illegally).
If your hazard warning lights are left on while you are driving, any signalling with your indicators will not be able to be seen.
- Driving in bad weather. With your hazards on and rain or snow already blurring road visibility, other drivers may not be able to tell which lane you’re in or if you’re changing lanes.
Turn on your headlights and taillights in inclement weather instead. If the weather is bad enough that you feel hazard lights are truly necessary, pull off the road and stop until conditions improve.
- Driving in heavy traffic. While your hazards can make you more visible, they can also make it challenging for other drivers to anticipate what you’re doing and where you’re headed, since turn signals are disabled when hazards are activated in some cars.
- Parking illegally. Parking illegally is never a good idea. But if you do park illegally, turning on your hazard lights doesn’t make it legal. Keep driving until you find an appropriate parking spot and won’t be blocking traffic.
A turn signal will do the job. If you’re slowing down to exit the highway due to an unexpected problem, think twice before using your hazards.
As we mentioned before, turn signals are generally disabled when your flashers are on. That can make it difficult for other drivers to know where you’re going and could result in a crash.
The traffic expert is DCC Nnamdi Ikeh-Akabogu, DCC Morning and Evaluation (M&E), Special Duties and External Relations (SEDER), FRCC HQ, Abuja