What indicates a significant concern during a Category B Incursion?

A significant concern during a Category B Incursion is indicated by a direct collision threat requiring action. This category of incursion is classified when an aircraft or vehicle enters a runway or taxiway in a manner that poses a serious risk of collision with another aircraft. A direct collision threat necessitates immediate action to mitigate the risk, highlighting the critical importance of situational awareness and the need for prompt communication and response to ensure safety in airport operations.

In this context, the focus is on situations where immediate intervention is necessary to prevent potential accidents or incidents involving aircraft on the runway or taxiway. Understanding this is vital for airport personnel as it helps prioritize safety measures in high-risk scenarios.