Blue colored text on the ECAM screen signifies:

The blue colored text on the ECAM screen is used to indicate actions that need to be accomplished, or to highlight limitations. This distinct color serves a clear purpose in the cockpit, as it draws the pilots' attention to specific messages that require their immediate action or consideration during flight operations. For example, it may indicate procedures that pilots must follow in response to certain conditions or system statuses.

The use of blue for these messages helps to differentiate them from other types of notifications that may appear on the ECAM, ensuring that essential actions or limitations are easily recognized amidst the various information being presented. This color coding contributes to better situational awareness and clearer communication of the aircraft's operational status, thereby enhancing safety and effectiveness in managing potential in-flight scenarios.