What should a guard do if they find an unsecured door?

When a guard finds an unsecured door, the correct action is to secure it and notify their supervisor. This course of action is best because it ensures immediate safety and security of the premises by preventing unauthorized access. Securing the door minimizes the risk of theft, vandalism, or other security breaches.

Notifying a supervisor is crucial because it allows for proper documentation and accountability. The supervisor may need to take further steps, such as adjusting patrol strategies or investigating how the door became unsecured. This layer of communication is essential for maintaining high security standards and ensures that the guard’s actions are aligned with the organization's protocols.

In contrast, simply leaving the door unsecured could lead to significant security issues, while ignoring it could result in a liability if an incident occurs. Therefore, the most responsible and effective response is to secure the door and inform a supervisor, thereby upholding the integrity and safety of the environment that the guard is responsible for.