For how long can a railroad operate over non-compliant track under the authority of a 213.7a person?

The correct duration for which a railroad can operate over non-compliant track under the authority of a 213.7a person is 30 days. This provision allows for temporary relief from compliance, ensuring that limited operations can continue while addressing the deficiencies of the track.

During this 30-day period, the railroad must take appropriate actions to rectify the non-compliance issues. This is an important aspect of track safety regulation, as it provides a structured timeframe for necessary repairs or maintenance without completely halting rail operations. The emphasis on a finite period allows for both operational flexibility and the importance of adhering to safety standards.

In other options, the durations exceed the allowable time frame set for operating over non-compliant track, which would not align with the regulatory requirements in place to ensure safety and compliance.