The following words or terms when used in this Part shall have the following meanings unless the context clearly indicates otherwise:
"Map mileage" means the distance between areas designated in Oklahoma by the Oklahoma Department of Transportation and in other states by the Rand McNally Road Atlas. Non-employees may use an official Oklahoma state map for this purpose. Distances between towns are generally the shortest distance by public roads from the center of one town to the center of the other town.
"Overnight travel " means the non-employee or employee is in travel status for more than 18 hours, does not live or have their official duty station within 60 map miles of destination, and it is reasonable for the employee or non-employee to get necessary sleep and rest to complete work.
"Per diem" means reimbursable charges for meals while in overnight travel status.
"Subsistence" means reimbursable charges for lodging while in overnight travel status.
"Travel status" means the absence of an employee from the official station or non-employee from his or her home while performing assigned official duties.
"Vicinity travel" means any travel made for official purposes not included in the calculation for map mileage.