When should hazard warning signals (4-way flashers) be used?

Hazard warning signals, commonly referred to as 4-way flashers, are designed to alert other drivers to potential hazards or unusual situations on the roadway. The correct context for their use is when a driver needs to perform emergency vehicle maintenance on the road shoulder, which signals to other drivers that there is a vehicle stopped and potentially obstructing or endangering the flow of traffic.

In this scenario, activating hazard lights allows other motorists to be aware of the situation, reducing the likelihood of an accident by encouraging them to proceed with caution around the disabled vehicle. Emergency maintenance situations can pose various risks, and using 4-way flashers serves as a crucial safety measure under such circumstances.

While certain driving situations, like navigating through a tunnel or driving a heavy truck or bus uphill, require attentiveness and safe practices, they do not specifically warrant the use of hazard warning signals. The primary purpose of these signals is to convey a temporary hazard to other road users, making the correct choice particularly relevant to emergency maintenance situations.