How Far Should a Generator Be From Your House to Be Safe?

Your generator should be at least 20 feet from any door, window, or vent — that's the minimum safe distance the CPSC recommends. But distance alone doesn't guarantee safety. CO from a generator can still drift into your home, especially if the wind shifts or a window is cracked. This matters right now. It's mid-July, hurricane season is active, and storms across the Southeast and Midwest are knocking out power. Every outage is a moment when someone drags a generator out of the garage and starts it up too close to the house. According to the CDC, portable generators are responsible for more CO poisoning deaths than any other consumer product — roughly 85 deaths per year on average, and that number climbs after major storms. Carbon monoxide has no smell, no color, and no taste — a family can be poisoned in their sleep and never know the source was the generator humming 10 feet from the back door. This post covers exactly how far to place your generator, why common setups still fail, what CO levels from generators can do to your body, and what to do the next time the power goes out.

How Far Should a Generator Be From Your House?

The CPSC is specific: keep your generator at least 20 feet away from any door, window, or vent. That includes your garage door, dryer exhaust vent, bathroom fan vent, and central AC intake. All of these are pathways for CO to enter your home. Twenty feet is the floor, not the goal. More distance is always better. The exhaust should point away from your house and away from your neighbors' homes. If wind is blowing toward the house, even 20 feet may not stop CO from drifting inside through gaps around windows and doors. Never run a generator inside a garage — even with the door fully open. The CPSC has documented cases where CO built up to deadly levels in an attached garage within minutes of startup, then seeped into the living space. CO from a generator running in a garage can reach life-threatening concentrations inside the home before a standard alarm ever sounds. If your backyard is small, choose the corner farthest from all openings. Avoid placing it under a covered patio or carport — even open-sided structures trap exhaust. You can learn more about Generator Carbon Monoxide: Why It Kills and How to Stay Safe safe generator use and the sources that kill most in outage situations. Takeaway: Twenty feet from every opening, exhaust pointed away from the house, and never — not once — inside a garage or enclosed space.

Why Do So Many Generator CO Deaths Happen Even When the Generator Is Outside?

Most people assume outside means safe. It doesn't. CO is heavier than warm air but lighter than cool air — it moves unpredictably. Wind direction, the layout of your home, and the location of your vents all affect where CO goes after it leaves the exhaust. Here's what the data shows. The CDC reports that CO poisoning deaths spike sharply in the 24 to 72 hours after hurricanes and major storms — exactly when generators are running the most. Many of those victims had their generators outside. The problem isn't just where the generator sits. It's how close, which way the exhaust faces, and whether any windows or vents are open nearby. There's also a timing problem. Standard CO alarms are built to the UL 2034 standard, which means they're designed to sound at 70 PPM — but only after 60 to 240 minutes of sustained exposure. A generator near your home can push CO indoors fast. The 70 PPM Standard Was Designed to Alarm Late — Here's Why That's a Problem explains how this standard works and why it misses early exposure entirely. By the time a standard alarm goes off, CO may have been building in your bedroom for over an hour. Symptoms like headache and nausea often get blamed on stress, heat, or a bad night's sleep — not poisoning. Takeaway: Outside placement reduces risk but doesn't eliminate it — wind, vents, and alarm delay gaps mean CO can still reach dangerous levels before anyone wakes up.

What Does Generator CO Actually Do to Your Body?

CO — short for carbon monoxide — is a gas your body absorbs faster than oxygen. When you breathe it in, it binds to hemoglobin, which is the part of your blood that carries oxygen. Once CO takes up that space, your organs stop getting the oxygen they need. Your brain is the first to suffer. According to NIOSH, exposure at 1,200 PPM causes loss of consciousness within two to three breaths and can be fatal in minutes. Generators near a house can push indoor levels past 1,000 PPM quickly — especially if windows are cracked or a vent is nearby. Lower levels hurt you too, just more slowly. At 70 PPM, headaches start within a few hours. At 150 PPM, How Long Does Carbon Monoxide Poisoning Take? The Full Timeline you may have two hours or less before serious poisoning begins. At 400 PPM — a level generator exhaust can produce indoors within 30 minutes in a poorly ventilated space — CO is life-threatening in under three hours even for a healthy adult. The cruelest part is that CO makes you too confused to act. People report feeling too dizzy to stand, too tired to call for help. Many victims are found where they fell asleep — in bed, on the couch. This is why Carbon Monoxide Poisoning While Sleeping: The Real Risk is one of the most dangerous scenarios, especially during summer storm outages. Takeaway: CO doesn't just make you sick — it disables your ability to recognize you're in danger, which is exactly why early detection matters more than any other precaution.

What Should You Do Right Now?

• Measure your distance — go outside and physically count 20 feet from every door, window, and vent before you place your generator. Use a tape measure if you're unsure.
• Point the exhaust away from your home and your neighbor's home — check wind direction before you start the generator and adjust the position if needed.
• Never use a generator in a garage, carport, shed, or any enclosed or semi-enclosed space — even with ventilation, CO builds faster than it escapes.
• Place a working CO alarm on every level of your home and inside every sleeping area before you start the generator — not after.
• Choose a CO detector that shows live PPM readings so you can see CO building before it reaches alarm levels — a beeping alarm alone tells you nothing until it's already dangerous.
• If your CO alarm sounds or anyone feels sudden headache, nausea, or dizziness while the generator is running — get everyone outside immediately and call 911.
• After a storm outage, check that your CO detector is still functional — power surges and old batteries can disable the very device you're counting on.

During a summer storm outage, every minute counts — and the last thing you want to discover is that your CO detector is an old alarm-only unit that can't tell you whether the air in your bedroom is at 10 PPM or 200 PPM. That's the gap the AirShield™ 3-in-1 Portable Carbon Monoxide Detector was built to close. It shows you live CO levels in real time on a clear OLED screen — along with temperature and humidity — so you know exactly what you're breathing, not just when the alarm screams. It works anywhere in the world on 100–240V power, it's UL listed, and it uses an electrochemical sensor with a patented Smart M8 Chip for accuracy you can trust. If you want to see the air in your home during the next outage instead of just hoping for the best, visit airshield.store.