When the power goes out, your generator becomes the most important machine in the house. But the moment most people get wrong isn't starting it — it's refueling it. Done carelessly, refueling a generator in the dark, in bad weather, with a heavy gas can is one of the most dangerous things you'll do all storm. Here's how to do it safely.

Why generator refueling is riskier than it looks

A running generator is hot, and gasoline vapor ignites easily. Pouring fuel near a hot muffler or onto a running engine can cause a flash fire — this is the most common generator-refueling injury. Add slick conditions, poor lighting, and the awkward angle of tipping a full 5-gallon can, and spills become almost inevitable. During an outage the stakes are higher: spilled fuel is fuel you may not be able to replace, and fumes near a generator are a real hazard.

The right way to refuel a generator

1. Shut it down and let it cool. Turn the generator off and wait until the engine and muffler are cool to the touch. Refueling a hot engine is the mistake that causes fires.
2. Move fuel handling away from ignition sources. No smoking, no open flames, and keep the generator away from the house while it runs.
3. Refuel on a stable, level surface so the tank fills evenly and you can see the fill line.
4. Don't top off. Fuel expands as it warms — leave room to prevent overflow.
5. Wipe up any spills and let vapors clear before restarting.

Common mistakes

• Refueling while it's running — convenient, but the leading cause of generator fires.
• Overfilling the tank — leads to overflow onto a hot engine.
• Lifting and tipping a full can in the dark — a full 5-gallon can weighs 30+ pounds; aiming it by flashlight in the rain is how spills happen.
• Storing too little fuel — many people keep one can and run out mid-outage.

A cleaner, safer way to move the fuel

Tipping and pouring is the weak link. A battery-powered fuel transfer pump lets you keep the gas can flat on the ground and pump fuel directly into the tank through a nozzle — no lifting, no tilting. An auto-stop feature cuts the flow when the tank is full so you can't overfill, and a steady flow rate fills the tank in under a minute without splashing.

For storm prep, a pump with a USB-C power option is worth considering — you can run it from a power bank or USB charger when fresh AA batteries are hard to find. DeWay offers auto-stop models built for exactly this kind of controlled, hands-free transfer. (Planning your supply? See our guide to storing gasoline safely at home.)

FAQs

Can I refuel a generator while it's running? No. Always shut it off and let it cool first. Refueling a hot or running engine risks a fire.
How much fuel should I store for a power outage? Many homeowners keep enough for 2–3 days of intermittent use, stored in approved containers and treated with stabilizer if it will sit.
What's the safest way to transfer gas into a generator? Keep the can on the ground and use a transfer pump with auto-stop rather than lifting and pouring.