Electric Generator Safety

Follow These Guidelines to Make Sure That Your Generator Is Working Safely

Some customers prepare for the possibility of power outages by buying an electric generator as a standby system to keep lights and appliances running until service is restored.

A generator may be able to help save food in your refrigerator or freezer during a prolonged outage, let you keep your home office running, or power other essential equipment. Generators can be expensive and noisy. They can also pose serious safety hazards to you and to others, so please follow all safety instructions provided by the manufacturer.

The law requires that customers with a permanently installed or portable generator do not connect it to another power source, such as PG&E's power lines. If you own and operate a generator, you are responsible for making sure that electricity from your unit cannot "backfeed," or flow into PG&E's power lines. For safety's sake, be sure to use your generator correctly. If you do not, you risk damaging your property and endangering your life and the lives of PG&E line workers who may be working on power lines some distance from your home.



Permanent Standby Generators

When a generator is permanently connected to a customer's electric system, it energizes the building's wiring. This type of installation requires a device that prevents the generator from being connected to PG&E's power lines. Only a qualified professional, such as a licensed electric contractor, should install a permanent standby generator.

Permanent Generator


Follow these safety tips:

  • A double-pole, double-throw transfer switch (see diagram A2) is the recommended device to keep your generator from backfeeding into PG&E's system. The switch also keeps PG&E's power from re-energizing your house wiring while your generator is running, protecting your generator, wiring and appliances from damage when your service is restored.
  • Have all additions to your house wiring inspected by your city or county building department.
  • When installation is complete, call PG&E to let us know about your back-up system. We will make a note in our records to remind our workers of your generator if they are working on an outage in your area. In some cases, PG&E line workers may ask to check your electric generator transfer switch for safety.
  • If you already have a permanently installed standby generator but you don't know if it's installed properly, call your local building inspector or a licensed contractor for help.

You are responsible for any injuries or damage to your property, your neighbors' or PG&E's, from an improperly installed or operated generator.

Portable Generators

Portable generators are designed to be connected only to selected appliances or lamps. These generators never should be connected directly to a building's wiring system.

  • Before starting your generator, carefully read and follow all of the manufacturer's instructions.
  • Be sure that the total electric load on your generator will not exceed the manufacturer's rating.
  • Always locate your generator where its exhaust will vent safely.
  • Prioritize your needs. Use the lowest wattage light bulbs that provide a safe level of light, reserving power for additional lighting elsewhere or a small appliance. Remember that the greater the load on your generator, the more fuel it will use.
  • Keep cords out of the way so they don't present a tripping hazard—especially in dimly lit doorways or halls. Never run cords under rugs or carpets where heat might build up or damage to a cord may go unnoticed.
  • Extension cords must be properly sized to carry the electric load. Overloaded cords can overheat and cause fires or damage to equipment.

Download printable generator safety guidelines (PDF, 348 KB).