When covering up primary lines, which phase is covered first?

When covering up primary lines, the very first phase that is set is covered first. This approach is essential for maintaining safety and ensuring that all phases are effectively managed during the work process. Prioritizing the first phase helps in reducing the risk of electrical shock or inadvertent contact with energized lines that may still be live.

By covering the first phase set, workers can systematically approach the task in a manner that maintains a clear sequence of operations. This method also allows for easier handling and reduces confusion, minimizing the potential for errors during the covering process.

In contrast, other choices do not align with this safety and operational efficiency strategy. Covering the last phase set could leave workers exposed to hazards if the first phases remain accessible. Randomly selecting which phase to cover can lead to disorganization and increase risks. Covering the highest voltage phase first does not consider the order of operation established during the setting of the lines, which is critical for ensuring a safe working environment.