8. Fire engines used to be red. Yellow-green is now the preferred color. Why the change?
The eye is more sensitive to the new color. Also, people who are color blind have trouble seeing red (and green, too, but the yellow helps make it visible.) I have noticed some blue in the green of traffic signals; presumably that is to help red/green color blind people distinguish when the green light is on.
The change from red to yellow-green as the preferred color for fire engines can be attributed to several reasons. To understand why this change occurred, it is essential to consider the history and evolution of fire engine colors.
1. Visibility: The primary purpose of using a specific color for fire engines is visibility. Fire engines need to stand out clearly, especially in emergency situations where they need to navigate through traffic quickly. Red was historically chosen as it was a vibrant, attention-grabbing color. However, studies have shown that yellow-green is more effective in terms of visibility, especially during daylight hours. This color is easier to spot, even from a distance, allowing other drivers to recognize and yield to emergency vehicles promptly.
2. Contrast with surroundings: Yellow-green stands out more distinctly against the typical urban environment, which is filled with reds and oranges (e.g., traffic lights, road signs, traffic cones). This contrast helps fire engines become more noticeable and distinct on the road, reducing the likelihood of accidents and facilitating their quick and safe passage.
3. International standards: The change in fire engine color is also influenced by international standards. The International Organization for Standardization (ISO) has recommended the use of lime-yellow (a specific shade of yellow-green) for emergency vehicles, including fire engines. This standardization ensures consistency and facilitates interoperability between emergency services across different regions.
4. Psychological factors: Another factor that contributed to the adoption of yellow-green is its psychological impact. Research suggests that yellow-green is associated with safety and caution, making it an appropriate color choice for emergency vehicles. This color can convey a sense of urgency and trigger a responsive behavior in other road users, encouraging them to yield and clear a path for the fire engine.
In summary, the shift from red to yellow-green as the preferred color for fire engines was driven by factors such as increased visibility, contrast with surroundings, international standards, and psychological impact. These considerations collectively aim to improve the effectiveness and safety of fire engine operations during emergencies.