How to Run a Generator Safely in a Power Outage

The power has been out for hours, the house is cooling, and the generator is sitting in the garage. The exhaust is the thing that kills, not the machine. Carbon monoxide has no smell and no color, and a generator run in an attached garage reaches lethal levels within minutes even with the door wide open.

Put the generator outdoors and nowhere else

Outdoors only. Never a garage, never a basement or crawlspace, never a covered porch, never a shed. Set it on dry ground at least 20 feet from the house with the exhaust pointed away from every door, window, dryer vent, and soffit vent, including a neighbor's. Wind shifts, so pick a spot with distance to spare.

Confirm working CO alarms inside before starting it

Check that a carbon monoxide alarm on every level of the house is powered and passes its test button before the engine ever turns over. An alarm that has been chirping since last spring is not protection. If one sounds while the generator runs, get everyone outside into fresh air and call 911 from outside.

Deliver the power through cords or a transfer switch

Never plug a generator into a wall outlet or a dryer outlet. That backfeeds the utility line, can electrocute the crews restoring power, and is illegal in most places. The two legitimate options are a transfer switch installed by a licensed electrician, or heavy outdoor-rated extension cords run directly to each appliance.

Size the load before plugging anything in

A refrigerator, a furnace blower, and a few lights are a modest load. A well pump, a water heater, or electric baseboard heat is a different category, and motors draw two or three times their running watts at startup. Add the running watts of everything at once, then add the largest starting surge on top.

Refuel with the engine off and cooled

Shut the engine down and give it several minutes before opening the fuel cap. Gasoline spilled on a hot muffler ignites. Store cans outside the living space, never in a basement or next to a furnace, and use fresh fuel with stabilizer rather than last winter's can.

Keep it dry without wrapping it

Water in the outlets is a shock hazard, so do not run one in driving rain or standing snow. Use an open canopy or a generator tent that leaves all four sides ventilated. Never drape a tarp over a running generator, which traps both heat and exhaust.

Test it before the season, not during the outage. Start it in October, run it under load for 20 minutes, and confirm the cords and CO alarms are ready while it is still light out.

Accept what it cannot do. A portable unit runs a handful of circuits, not a whole house. Trying to stretch it past that is where the improvised wiring and the dangerous shortcuts begin.