11. They were also employed as warning devices in heavy fog, and for alarms and ceremonies. 12. New technology aside, Gray has his own warning device . 13. The warning device is set to ring 25 to 40 seconds before an imminent crash. 14. Our railroad signal system as well as any warning devices are all driven by commercial power, 15. These failures have also resulted in updated safety policies and adjustments of equipment and warning devices . 16. Although the 25 m / s winds activated warning devices , the train proceeded across the bridge. 17. Hughes provides stereos, theft-deterrent systems, engine and transmission control systems, and collision warning devices for GM vehicles. 18. Both of these warning devices were powered by an electric generator driven by the number one engine. 19. Hughes makes stereos, theft-deterrent systems, engine and transmission control systems, and collision warning devices for GM vehicles. 20. A total of 44 states have at least one railroad crossing having a wigwag as its warning device .
