What defines a major security breach on a vessel?

A major security breach on a vessel is defined by unauthorized access to secure areas. This is critical because secure areas are typically where sensitive equipment, information, or high-value cargo is stored, and gaining unauthorized access can pose significant risks to the safety and security of the vessel, crew, and cargo. Ensuring that only authorized personnel can enter these areas is fundamental to maintaining the integrity of a vessel's security protocols.

In contrast, minor inconveniences for the crew do not constitute a security threat or breach. Routine security checks are standard procedures intended to prevent breaches and maintain safety rather than indicate a breach. The loss of cargo during transit, while concerning, does not directly relate to the security of the vessel; it could result from various factors, including operational errors or weather conditions rather than security violations. Thus, unauthorized access to secure areas stands out as the defining characteristic of a major security breach on a vessel.