Marine signals

There are approximately 2,000 signals used for marine visual communications by flag, semaphore or lights and for encoded radio telegraph messages. While this international system has helped to secure safety of navigation and to protect human life at sea, ambiguities, loopholes and occasional defiance of maritime law has undermined the cooperative action that such signalling systems hope to evoke. Compared to surface signalling sub-surface international communications are less developed. Since the advent of a least four nations' nuclear armed submarines cruising in international sea depths, this poses a risk of accident or incident of serious proportions.