ATSF
| Atchison Topeka & Santa Fe | 8 |
BCOL
| Canadian National Railways | 3 |
BN
| Burlington Northern | 1 |
CN
| Canadian National Railways | 5 |
COP
| City of Prineville Railway | 2 |
CP
| Canadian Pacific Railway | 2 |
FCP
| Ferrocarril Del Pacifico | 1 |
MILW
| Milwaukee Road | 8 |
NJT
| New Jersey Transit | 1 |
NP
| Northern Pacific | 1 |
PGE
| Pacific Great Eastern | 1 |
SBC
| Ferrocarril Sonora Baja California | 2 |
SCAX
| SOUTHERN CALIFORNIA REGIONAL RAIL AUTHORITY | 1 |
SDAE
| San Diego & Arizona Eastern | 2 |
SPMW
| Southern Pacific Maintenance of Way | 2 |
SPSX
| Progress Rail Services Corp | 3 |
SRGX
| SRGX | 1 |
TCG
| Tucson Cornelia and Gila Bend Railroad Company | 1 |
UP
| Union Pacific Railroad Company | 5 |
UPMW
| UPMW | 1 |
UPP
| Union Pacific Passenger | 1 |
WP
| Western Pacific | 1 |
WPMW
| Union Pacific Railroad Company | 7 |