Which of the following is NOT a requirement for a watch or clock used in train operations?

The statement regarding the requirement that a watch or clock used in train operations must vary from the correct time by no more than 1 minute is not accurate. In operational settings, accuracy is crucial, and while timekeeping devices should indeed be close to the correct time, specific thresholds can vary based on regulations or operational policies. The other options highlight essential characteristics of watches or clocks that are vital for ensuring safe and effective train operations.

For example, a watch or clock must display seconds to facilitate precise timing, as train schedules and movements often depend on minute-by-minute accuracy. Being in good working condition is crucial because any malfunction could lead to operational errors or delays. Finally, comparing the watch or clock with a designated time source ensures that the device is synchronized correctly, which is critical in maintaining the safety and efficacy of railroad operations. Thus, the requirement related to the allowable variance from the correct time is not essential under the regulations that govern these operational tools.