How must switches be secured when not in use?

Securing switches when they are not in use is crucial for maintaining safety and operational integrity on the railway. The correct method of securing switches is to ensure that they are locked, hooked, or latched if they are equipped with these mechanisms. This prevents any unintended movement of the switch, which could lead to derailments or accidents if trains were to be directed incorrectly onto a track that is not intended for their travel.

By utilizing locks, hooks, or latches, you create a reliable safeguard that limits the possibility of unauthorized or accidental alterations to the switch position. This approach supports the overall safety protocols in train operations, as it allows for clear and secure control over track routing and prevents human error.

The other options signify practices that could compromise safety on the railway. Leaving switches in a random position does not provide any assurance of control or security and can lead to hazardous situations. Closing a switch securely alone, without additional locking mechanisms, could still leave it vulnerable to being reopened or misconfigured. Marking a switch with a sign does not provide any physical security; signs alone serve merely as a warning and cannot prevent unauthorized access or movement of the switch. Thus, securing switches with a locking mechanism is essential for safe rail operations.