Where public roads, highways and streets cross above railroad tracks which are used or proposed to be used for transporting freight cars, minimum clearances as prescribed in NAC 705.020, 705.030, 705.050 and 705.060 must be provided, except that at the time of installation of the public road, highway or street, a minimum overhead clearance of 23 feet above the top of the rail must be observed.
Nev. Admin. Code § 705.066
NRS 704.280