As nearly everyone who has driven a vehicle on US roads at some point is well aware, police vehicles that are attempting to respond to an emergency will utilize both red and blue lights atop and alongside their vehicles to help warn other drivers of their passing. These lights are well-known as signs that drivers should pull over and allow police to make their way to their destination as quickly as possible — and did you realize there are actually several reasons why red and blue were chosen as the primary colors for this purpose?
At LED Equipped, we’re proud to outfit numerous first responders with various emergency vehicle LED light bars and other light options, plus things like sirens, speakers and more to ensure that our clients can always make their presence on the road known to maintain safety at all times. We’re often asked simple questions by those who are new to this realm, and one of the simplest is this: “Why are police lights primarily red and blue?” While some might think this has to do with the red, white and blue colors that represent the US, this is actually just a convenient coincidence — here’s some of the actual psychology behind the use of red and blue for police lights, and why these are the primary colors used.
A well-known theme within the world of psychology is color association, which refers to the inherent meaning that different colors carry for people. It’s why we see red flags in some contexts as a warning, or associate blue with feelings of sadness or melancholy. This is important to consider when it comes to emergency vehicles, as the colors you choose can subconsciously influence the way people react.
Red has long been known as a danger sign, which is likely the reason that it’s used on stop signs and traffic lights in addition to emergency vehicles. Blue has a calming effect for many people, and is also fairly unique among colors — according to one study, blue is only seen in about 15 percent of natural habitats. This makes blue an eye-catching color that can quickly gain attention.
And because police warning lights are all about getting the attention of drivers, red and blue are the perfect colors to use. However, there are actually several other reasons for their use that really drive things home — read on to learn more.
Blue Helps Differentiate From Brake Lights
For many of the same reasons we just went over above, brake lights from US vehicle manufacturers have long been red as well. This is because red is known as nature’s “stop” color, one that our brains have evolved to pay special attention to. However, this creates a problem when you’re trying to differentiate your police vehicle’s emergency lights from the standard brake lights — after all, if both are red, then drivers may just think you’re stopping for some other reason and not react as quickly.
This is where blue comes in as a complementary color. While blue is not nearly as associated with “stopping” as red is, it does help to provide some differentiation so that drivers can more easily tell that your vehicle is an emergency response vehicle. And in a situation where every second counts, this can be crucial.
Simply put, there are very few other situations on the road where drivers will see both red and blue light together like this, so it makes it easier for drivers to quickly identify an emergency situation and take appropriate action. The red provides the initial shock of warning, while the blue helps to clarify and cement the meaning of the red lights.
Red and Blue Are Easily Distinguishable From Each Other
Another factor to consider is that of contrast. When you’re looking at police lights from a distance, you need to be able to easily see the difference between the red and blue lights. This is another area where both colors are useful, as they provide a high level of contrast from one another.
In fact, research has shown that people are able to see the difference between red and blue emergency lights from distances of up to 1 mile away, making them easily visible in a variety of situations. And while other colors like green or yellow could also provide some contrast, they don’t carry the same weight in terms of danger and warning that red and blue do.
Visibility for People With Color Blindness
While more research is still being done here, much of what we know so far indicates that people who deal with color blindness are typically able to see either red or blue — they may miss one of these, but missing both is extremely rare. This is another important consideration, as a non-trivial number of people in the US have some form of color blindness.
This means that having red and blue emergency lights is actually more inclusive for people who may have trouble distinguishing certain colors than if you were to use a green or yellow light. And because inclusion is so important when it comes to emergency services, this is yet another factor in favor of using these colors.
Day Vs Night
While many police response issues take place at night, where bright LED lights will stand out regardless of color, there are still a number of times when daylight response is necessary. In these cases, you need lights that will still stand out in the midst of all the other colors that people see during the day.
Here again, blue and red work well together. Blue is still a fairly rare color in nature, so it will stand out even in bright sunlight. And while red is a bit more common, it’s still not as ubiquitous as green or yellow, making it easier to spot in the midst of all the other colors that people see during the day.
While you might see some of these other colors for less vital warning types, such as pedestrian crossing lights, it’s still important to use a color that will stand out for emergency situations. After all, lives may depend on it. Red and blue lights are used as warning signals for a reason: they’re highly visible and easily distinguishable from one another. This makes them perfect for use as emergency vehicle lights, as they provide a clear warning to other drivers that something is happening and they should take action.
Another theme that’s vital here, and which makes the colors used on police lights all the more impactful: These lights are designed to be flashing.
When you see a solid light, your brain is wired to think that it’s just another car on the road. But when you see a light that’s flashing, your brain immediately registers it as something different — and this is especially true for emergency lights.
The bright flashes of red and blue help to grab your attention, and they also help to communicate the urgency of the situation. This is why many emergency vehicles will use a combination of flashing red and blue lights, as it provides the most information to other drivers.
Civilians Should Never Use Red and Blue Lights
For many of the reasons we’ve gone over above, and additionally to ensure the safety and response times of actual police officers and other first responders, it’s crucial that civilians never use red and blue emergency lights on their own vehicles.
While there are some types of warning lights that can be used by civilians, such as those that indicate a disabled vehicle, these should never be the same colors as those used by emergency vehicles. This helps to ensure that people know at a glance which vehicles they should be pulling over for and which ones they can safely ignore.
Police lights, especially red and blue, have a lot of symbolism behind them. They’re not just there to get your attention — they’re also communicating a message about the situation at hand. By understanding what these colors mean, you can better understand why police use them in the field. For more on any of our police or other first responder LED lights, speak to the team at LED Equipped today.