Which of the following are potential safety hazards?

Overhead and underground power systems present significant safety hazards, as they pose risks of electric shock, electrocution, and injuries related to contact with live wires. Technicians working near or with these systems need to be acutely aware of their presence and follow safety protocols to mitigate risks.

While signal timing errors can lead to dangerous traffic situations, they do not represent a direct physical safety hazard in the same way that working near power lines does. Similarly, conduit repairs, while potentially hazardous in certain contexts (e.g., excavation work), generally do not carry the same level of immediate risk associated with high-voltage power. Line painting, although it can pose some risks due to working near traffic, tends to be less hazardous overall compared to the dangers presented by power lines. Hence, the focus on overhead and underground power as the most significant safety hazard is valid.