A small vessel engaged in diving operations should exhibit which signal to indicate its activity?

A small vessel engaged in diving operations is required to exhibit a flag with a white square and a red diagonal stripe, also known as the Alpha flag. This signal is specifically defined by the International Regulations for Preventing Collisions at Sea (COLREGs) and is universally recognized as a request for vessels to keep clear of the area in which diving operations are taking place.

Displaying the Alpha flag serves to alert other vessels of the potential hazards associated with divers in the water and emphasizes the need for heightened caution. The distinct design of this flag makes it easily identifiable from a distance, ensuring that nearby vessels can take appropriate measures to avoid interference with the diving operations.

In contrast, while other flags such as a yellow flag and a blue flag may serve various purposes in maritime signaling, they do not specifically indicate diving activities. Therefore, it is crucial for safety that the correct signal is used to effectively communicate the presence of diving operations to other vessels in the vicinity.