What federal regulation governs the Hours of Service law?

Answer: C — Part 228

The correct choice regarding the federal regulation that governs the Hours of Service law is found in Part 228. This regulation addresses the hours of service for railroad employees, particularly those involved in the operation of trains and other safety-sensitive functions. Part 228 outlines the requirements for working hours, rest periods, and sleep, ensuring that employees are not overworked and have adequate rest. This is crucial for maintaining safety standards in railroad operations, as fatigue can lead to accidents and mishaps. While Parts 218, 220, and 242 cover various aspects of railroad operations—such as safety regulations, drug and alcohol testing requirements, or track safety—none of them specifically address the regulations governing the Hours of Service law as comprehensively as Part 228 does. Understanding these regulations is vital for ensuring that railroads operate safely and that employees are fit for duty.