Which sign color is used to indicate immediate actions needed for traffic safety?

The color red is specifically used for signs that indicate immediate actions needed for traffic safety. This color is universally recognized as a signal to stop or to alert drivers to serious dangers and prohibitions. Examples of red signs include stop signs, yield signs, and regulatory signs that indicate restrictions requiring swift compliance. The use of red conveys a sense of urgency and serves to capture the attention of drivers, prompting them to take immediate action to ensure safety on the road.

In contrast, other colors like green are typically used for informational signs that provide guidance or indicate permissible actions, not emergencies. Blue signs often indicate services or information about road conditions, while yellow signs are used as cautionary warnings to alert drivers of potential hazards ahead but do not denote immediate actions.