__ should be conducted before turning control of power back to the MBTA.

The preferred protocol before turning control of power back to the Massachusetts Bay Transportation Authority (MBTA) is a Personnel Accountability Report (PAR). Conducting a PAR ensures that all personnel involved in an operation are accounted for and safe before resuming normal operations. This is particularly important in emergency situations, where ensuring the safety of crew members can prevent accidents and mitigate risks.

A PAR involves systematically confirming the status and location of all personnel on the scene. This report helps to identify any missing individuals and ensures that everyone is aware of the current conditions before any potentially hazardous actions, such as re-enabling power, are taken. This practice is crucial in maintaining safety protocols and ensuring effective communication among team members during operations.

Other methods listed, such as a quick PAR or roll call, while important in certain contexts, do not thoroughly meet the same level of accountability and safety assurance that a full PAR provides in this scenario. Thus, opting for the comprehensive approach of a PAR aligns with best practices for fire service operations concerning safety and control measures.