In CSOSS diagrams, what do interlocks primarily depict?

• A. The maintenance personnel responsibilities
• B. The color coding of components
• C. The target engagement coordinates
• D. The conditions and sequence steps that must be satisfied for progression

Answer: (D)

Interlocks illustrate the gating logic that controls when an operation can move to the next step. They specify the conditions, prerequisites, and sequence requirements that must be met before progression is allowed. This is what keeps the system operating safely and in the correct order—no step can advance unless the required states, signals, or feedback are satisfied. For example, a pump might only start after a valve is in the correct position and a temperature sensor reads within safe limits; the interlock ensures both conditions are true before energizing the pump. These interlocks are not about who does the maintenance, color coding of components, or target engagement coordinates, which are addressed in other parts of the diagrams or procedures.