[time-nuts] Do any regulations or laws require time to be accurate within 'x' seconds?

[Mike Clapp]

The North American Electric Reliability Corporation (NERC) under federal law
can fine of up to $1 million a day.

Standard BAL-005-0 ― Automatic Generation Control
Requirement 17. Each Balancing Authority shall at least annually check and
calibrate its time error and
frequency devices against a common reference. The Balancing Authority shall
adhere to the
minimum values for measuring devices as listed below:

Device Accuracy

Digital frequency transducer ≤ 0.001 Hz