Advisory: Generators and Electrocution Risk from "Backfeeding" Power Lines
In the aftermath of Hurricane Irene, FEMA's U.S. Fire Administration would like to remind first responders and the general public to assume that all power lines are energized.
Even though power may be out in your immediate area, improperly connected portable generators are capable of backfeeding power lines thought to be inactive. "Backfeeding" happens when you connect a portable generator directly to your home s wiring without having a functional transfer switch. Without a transfer switch, your portable generator s electricity can be sent back into the power grid from your house. This will energize the utility s power lines on your street and poses an electrocution hazard for first responders, utility workers, and your neighbors who may not know that your voltage is present on the shared lines.
In addition, as the utility's power is restored, your portable generator and house wiring may be severely damaged from improper usage.