covered service
For a train employee or a signal employee, any non-covered service at the behest of the railroad and performed for the railroad that is not separated from covered service by a qualifying statutory off-duty period of 8 or 10 hours or more. Such commingled service is counted as time on duty pursuant to 49 U.S.C. 21103(b)(3) (for train employees) or 49 U.S.C. 21104(b)(2) (for signal employees).