Which of the following is not a part of operations security (OPSEC)?

The process of operations security (OPSEC) focuses on protecting critical information and minimizing vulnerabilities that could be exploited by adversaries. Central to OPSEC are steps like identifying critical information, assessing vulnerabilities, and applying countermeasures to safeguard that information effectively.

In this context, while safety measures are important in general operational practices, they do not specifically fall under the realm of operations security. Safety measures are typically associated with protecting personnel and equipment from hazards, which may not directly correlate to the need to secure operational information. Thus, the implementation of safety measures is separate from the core elements of OPSEC, making it the correct choice as the option that is not a part of operations security.