Place a portable generator outside, at least 20 feet from the house, then run appliances on heavy-duty outdoor cords or through a transfer switch.
Every storm season, the same story shows up: a generator humming in the garage, a cord run through a cracked window, and a family waking up dizzy. Carbon monoxide is behind most of it. The gas has no smell and no color, so nothing warns you before symptoms start. Running a portable generator for home emergency power without that outcome comes down to three habits — outdoor placement, the right connection, and alarms that work.
How Far From The House Does A Portable Generator Need To Be?
At least 20 feet, measured from the house, and clear of doors, windows, vents, and sleeping areas.
FEMA and the CDC draw the same line. A portable generator goes outdoors, away from any building, and never inside a home, garage, basement, crawl space, or shed. Portable generators rank among the leading causes of carbon monoxide deaths during outages, and even at 20 feet, exhaust can drift back in through vents and open windows.
The CDC’s generator safety fact sheet pairs that distance rule with carbon monoxide alarms inside the home, tested often.
- Keep the machine on stable, dry ground, with the exhaust pointed away from your house and a neighbor’s.
- Do not treat a garage, screened porch, or shed as close enough to outside, even with the door wide open.
- Skip fans and propped windows. Air movement does not keep carbon monoxide from collecting indoors.
Alarms are the backstop. Battery-powered or battery-backup carbon monoxide alarms belong inside the home, and they need testing long before a storm, not during one. If anyone feels dizzy, weak, or nauseated while the generator runs, everyone moves to fresh air and stays there.
Wiring Appliances: Cords, Transfer Switches, And What Never To Do
Plug appliances straight into the generator with heavy-duty, outdoor-rated extension cords, or power your house wiring only through a transfer switch installed by a qualified electrician.
Those are the two approved paths, and the second is not a weekend project. A transfer switch has to match the generator’s capacity and meet local code, which is why a licensed electrician handles the installation. In return, house circuits run normally and the utility’s lines stay isolated from your machine. On the cord route, match the wire gauge to the load and the distance — a thin cord on a long run heats up.
Backfeeding is the move that gets people hurt. Running a cord from the generator into a wall outlet pushes power onto lines that utility crews believe are dead, and it can electrocute a line worker or a neighbor on the same transformer.
- Turn appliance loads off before starting the generator.
- Start the generator outdoors, following the owner’s manual for choke and fuel settings.
- Bring circuits back one at a time and keep the total below the generator’s rated capacity.
- Start the largest motor loads — refrigerator, freezer, furnace blower, well pump — one at a time so their startup surge does not trip the breaker.
No portable generator runs a whole house. Add up what actually matters during an outage — refrigeration, heat, a few lights, phone chargers — and match that number to the machine on your driveway. If you’re still shopping, our tested emergency generator picks for storm season compare capacity, run time, and fuel type side by side.
The same handful of mistakes show up in outage after outage.
| Common Mistake | Why It Backfires | What To Do Instead |
|---|---|---|
| Running it in the garage | Carbon monoxide builds up even with the door open | Set it outside, 20 feet from the house |
| Parking it near a window, vent, or door | Exhaust drifts straight back inside | Move it clear of every opening |
| Relying on a fan or open window | Air movement does not stop gas from collecting | Outdoor placement is the only fix |
| Plugging it into a wall outlet | Backfeed endangers utility crews and neighbors | Use a transfer switch installed by an electrician |
| Refueling while it runs or while hot | Vapors can ignite on hot engine parts | Shut it down, let it cool, then refuel |
| Powering everything at once | The breaker trips or the generator is damaged | Run essentials, one circuit at a time |
A Portable Generator For Home Emergency Power: Fuel, Rain, And Load Limits
Shut the generator down and let it cool before refueling, store every fuel container outside living areas, and never run the machine in rain or wet conditions.
Gasoline, propane, kerosene, and diesel models all follow the same placement and carbon monoxide rules. Fuel belongs in labeled, non-glass safety containers, stored away from where people sleep and eat. Water and electricity are the other bad pairing — a wet generator is a shock hazard, so keep it dry and shut it down if the weather turns. A tank typically runs the machine for hours rather than days, and heavier loads drain fuel faster, so check the manual for your model instead of guessing.
Load discipline carries through the whole outage. Run essentials, rotate them as fuel allows, and stagger the big draws so nothing trips. Do those four things — placement, connection, alarms, fuel — and the machine does the job you bought it for.
FAQs
Can I run a generator in my garage if the door stays open?
No. A garage counts as an enclosed space, and carbon monoxide builds faster than an open door can clear it. FEMA and the CDC put garages, basements, crawl spaces, and sheds off-limits with no weather-related exceptions. Stand the generator outside instead, at least 20 feet from the house and clear of vents, windows, and doors.
Do I still need carbon monoxide alarms if the generator sits outside?
Yes. Exhaust from a generator placed the recommended 20 feet away can still reach the house through vents, open windows, and doors. Battery-powered or battery-backup carbon monoxide alarms inside the home give you the warning your nose cannot, and they should be tested well before storm season rather than during an outage.
How much can one portable generator actually power?
Less than most people expect. Refrigeration, a furnace blower, a few lights, and charging devices usually fit; central air conditioning, an electric range, and a clothes dryer typically do not. Total the running watts of what you need, add the startup surge of the largest motor, and compare that figure with the generator’s rated capacity before the storm arrives.
References & Sources
- Centers for Disease Control and Prevention. “Generator Safety Fact Sheet.” Covers carbon monoxide risk, outdoor placement, and alarm requirements for portable generators.
- Federal Emergency Management Agency. “Use Generators Safely at Home.” Supports the 20-foot distance rule and the ban on indoor or enclosed use.
- U.S. Fire Administration. “5 Steps to Portable Generator Safety.” Source for cord, transfer switch, refueling, and fuel storage guidance.