Warning Lights & Traffic Signals
Warning lights are a vital piece of equipment for any emergency responder, whether they be police, fire, or health related. They allow an emergency responder to quickly, easily, and universally communicate to bystanders that an emergency is in progress and that they must stand aside. Emergency vehicle warning lights are available in many designs ranging from old-fashioned light bars placed on the outside of an emergency vehicle to subtle warning lights designed for unmarked, undercover vehicles. Today, almost all emergency vehicle lights are LED (Light Emitting Diode)-based due to the many benefits of LED lights: They have low energy consumption, are very cheap to buy, have incredibly longevity, outstanding durability, and a staggering variety of color options.
One feature of warning lights that is sometimes forgotten about is their effect on traffic signals. Many traffic signals are designed to allow emergency vehicles through when they flash their lights or sirens. How exactly this is accomplished varies from traffic light to traffic light, but emergency vehicle workers sometimes don't or even have a misunderstanding of how it is accomplished. Some work by detecting any strobe light, some by detecting the audio of a siren, some by radio, and the most advanced actually transfer information between the emergency vehicle and the light in order to identify the driver's identity. The simplest variety, those that work just by detecting any strobe light, have two flaws.
First, it's very easy for civilians to use emergency lights to mess with traffic signals that detect just any strobe light, either by buying an off-the-shelf light or improvising a light with parts bought at a local hardware store. This can cause deadly accidents and inconvenience to other drivers. Second, if an emergency responder doesn't fully understand how their warning lights interact with traffic signals, they can unknowingly stop traffic for extended periods of time. Because the easiest way to allow an emergency vehicle through is just to turn red, an emergency responder can accidentally cause a massive traffic build up by not realizing that keeping their warning lights on is forcing the lights to stay red. There have been situations where police officers responding to accidents have unknowingly stopped traffic for 30 or more minutes while resolving the situation.
As such, it's important for an emergency responder to be aware not just of how their warning lights work, but how traffic signals in their area are designed. This is not just so they don't inconvenience random civilians, but so they can strategically stop traffic, or allow traffic through if they have no need to stop traffic. Such simple strobe-triggered traffic light systems are being phased out due both to civilian abuse and being somewhat inconvenient for emergency responders depending on the situation. Smarter, more flexible traffic light systems allow emergency responders to sometimes directly control traffic even at great distances, allowing lights to turn red or green in ways that allow emergency responders to travel in the fastest and safest manner possible.
