Portable Generator Hazards

Portable generators are useful when temporary or remote electric power is needed. If used incorrectly, gasoline, kerosene, and other gas-powered generators can cause carbon monoxide poisoning, electric shocks, fires, and burns. Generator accidents can be fatal!  Review this fact sheet on safe generator use, P-01561 (PDF, 521 KB) to prevent generator accidents.

Carbon Monoxide (CO) Poisoning

Every year, people die in accidents related to portable generator use. For example, a young camper was killed by CO from a portable generator's exhaust tube adjacent to the victim's campsite. Most deaths involve CO poisoning from portable generators used indoors or in partially enclosed spaces. The Consumer Product Safety Commission reports that between 1999 and 2004, portable generators caused 172 CO poisoning deaths in the U.S.

Generators produce high levels of CO in their exhaust. Carbon monoxide around a generator and its exhaust tube can build up within minutes, even outdoors. Carbon monoxide can linger for hours, even after the generator is shut off. 

You cannot see or smell carbon monoxide. So even if you do not smell exhaust fumes, you may still be exposed to CO. 

You can help protect yourself by installing CO alarms (battery-operated or plug-in with battery back-up) in your home, RV, boat cabin, and other areas where carbon monoxide may be present. Carbon monoxide detectors should be certified to the latest UL safety standards. Test your CO detector monthly. Replace the batteries in the spring and fall when clocks are changed for daylight saving time.

This fact sheet (PDF, 333 KB) summarizes how to protect your family from carbon monoxide.

How to Avoid CO Poisoning

  • NEVER use a generator inside a home, garage, crawlspace, shed, or other enclosed area. Locate the unit outdoors and far from doors, windows, and vents. 
  • Always run your generator in a well-ventilated area, and only if you can vent its exhaust safely. Make sure the exhaust hose is placed far from other campers, tents, boats, cabins, etc. This fact sheet (PDF, 521 KB) details how to safely use a generator.
  • Install CO alarms in your home, RV, boat or other area where CO may be present.

Electrical Hazards

Generators pose a risk of shock and electrocution, especially if they are operated in wet conditions. If you must use a generator when it is wet outside, operate the generator under an open, canopy-like structure on a dry surface where water cannot reach it or puddle or drain under it. Do this without operating the generator indoors or near openings to any building, in order to help avoid the CO hazard. Dry your hands, if wet, before touching the generator. 

Use only heavy-duty extension cords specifically designed for outdoor use when connecting appliances to a portable generator. Make sure the wattage rating for each cord exceeds the total wattage of all appliances connected to it. Use extension cords that are long enough to allow the generator to be placed outdoors and far away from windows, doors, and vents to the home or to other structures (tents, other RVs, etc.). Check that the entire length of each cord is free of cuts or tears and that the plug has all three prongs. Protect the cord from getting pinched or crushed if it passes through a window or doorway. 

NEVER try to power the house wiring by plugging the generator into a wall outlet. This is sometimes called "backfeeding." Backfeeding is extremely dangerous! It presents an electrocution risk to utility workers and neighbors served by the same utility transformer. It also bypasses some of the built-in household circuit protection devices.

How to Avoid Electrical Hazards

  • Keep the generator dry. 
  • Dry your hands, if wet, before touching the generator. 
  • Use the right extension cord. 
  • Check your equipment and cords before use. Double-check where the exhaust is facing, where the generator is located, and the condition of the electrical cords. 
  • NEVER plug the generator into a wall outlet. "Backfeeding" is extremely dangerous and presents an electrocution risk.
  • Always follow the manufacturer's instructions when using your generator.

Fire Hazards

Generators and the fuel you use to run them can cause fire hazards. Never store fuel for your generator in the home. Gasoline, propane, kerosene, and other flammable liquids should be stored away from living areas, and only in properly labeled, non-glass safety containers. Do not store fuel near a fuel-burning appliance, such as a furnace or water heater. Before refueling the generator, turn it off and let it cool down. Gasoline spilled on hot engine parts could ignite.

How to Avoid Fire Hazards

  • Never store generator fuel in the home or near an ignition source. 
  • Before refueling the generator, turn it off and let it cool down.
  • Always follow the manufacturer's instructions when using your generator.


For more information

DHS webpage on Carbon Monoxide Poisoning and Protecting Your Family From Carbon Monoxide, P-01569 - Fact Sheet (PDF, 333 KB)

Data on carbon monoxide poisoning available through the Environmental Public Health Tracking Program.

DHS poster Warning! Use Portable Generators Correctly, P-45107 (PDF, 87 KB) and Using Generators Safely - Fact Sheet, P-01561 (PDF, 521 KB)

If you have additional questions, please call the Bureau of Environmental and Occupational Health at 608-266-1120. 

Prepared by the Wisconsin Department of Health Services, Division of Public Health, with funds from the Agency for Toxic Substances and Disease Registry, US Department of Health and Human Services. 

Last Revised: August 26, 2016