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Can You Leave a Generator Running Unattended?

Can You Leave a Generator Running Unattended?

A generator is an electrical device that converts mechanical energy into electrical energy. It is often used to provide backup power for homes, businesses, and even construction sites. Although most generators are easy to operate and durable, is it a good idea to leave them running unattended?  

You can leave a generator running unattended, but you should keep in mind that this is not a good idea. Generators produce carbon monoxide, which can build up very fast in enclosed spaces such as garages or sheds. You should always keep an eye on your generator when running it in an enclosed space.

In this article, I’ll take you through the risks involved in running a generator unattended and what you can do to mitigate them. I’ll also shed more light on how long generators can (and should) run. Let’s get started. 

Is It Safe To Leave a Generator Running Unattended?

Although you can leave a generator running unattended, doing so is ill-advised. Always keep a close eye on your generator, especially when running it in an enclosed space. Gas-powered generators are dangerous and can cause fires, carbon monoxide poisoning, and injury or death if used improperly.

A gas-powered generator should be used in a well-ventilated area and always kept far away from flammable materials such as wood, paper, etc. Not only are they very loud, but they also produce harmful fumes that can cause severe harm when inhaled over long periods.

There are many situations where it may be necessary to leave a generator running unattended. A common example is when you’re gone for long periods, such as for work or vacation. In such cases, you’ll need to make sure that the generator is in a safe place.

You should always leave your generator in a dry area with plenty of ventilation. This will help prevent damage due to condensation buildup inside the engine compartment (which could cause corrosion) or water accumulation around the unit (which could cause overheating).

Things To Consider Before Leaving Your Generator Running Unattended

Before leaving your generator unattended, there are a few things you should do to ensure that it is safe to do so.

  • Make sure you have a working smoke alarm. A fire can start in your house or garage while the generator is running and damage or destroy your electrical system and cause injury or even death. If possible, install an audible carbon monoxide alarm as well.
  • Ensure you have a fire extinguisher with a proper gauge rating for class B fires (the most common type associated with gasoline). Ideally, this will be an ABC-type extinguisher.
  • If you must use your generator indoors, then please take precautions to ensure there’s proper ventilation while running it. Open windows and doors so as not to suffocate yourself with carbon monoxide emissions that may occur if there is insufficient air circulation within the house.

Don’t Run Your Generator Indoors

The exhaust from a generator contains carbon monoxide, a colorless, odorless gas that is toxic to humans. Carbon monoxide is produced by the burning of fossil fuels (like natural gas or gasoline). It can be especially harmful if you inhale too much of it.

If you’re running your generator inside your home—for example, to power things like lights or electric heaters—you risk exposing yourself and your family to dangerous levels of carbon monoxide. This is because indoor spaces are often well-sealed, which traps additional air in the room instead of letting fresh air come through. 

With no way for the carbon monoxide to escape, the concentration builds up over time until it reaches potentially fatal levels. If left unattended with this kind of setup long enough (for example: overnight), then running a small portable generator could spell disaster for anyone inside!

As a good rule of thumb, you should avoid running a generator indoors, especially during the night when you’re less likely to monitor its function. Instead, you should set up a dry, well-ventilated space to house your device when in use. 

How Long Can You Run a Generator Continuously?

On average, a gas-powered standby generator can run up to 3,000 hours continuously while powering a medium-sized house. The figure changes depending on household appliances and a house’s overall size. Experts advise against running a generator longer than 500 hours due to the risk of overheating. 

There are a lot of factors that go into determining how long you can run a generator safely and continuously. The first thing to do is figure out your generator’s wattage. This can be done by checking the back panel specifications or using an online calculator. 

The next step is to estimate how much power it will take to keep your home running day in and day out when there’s no power coming from outside sources—and this requires some math skills. 

You should have a rough idea of how many appliances use electricity in your home, so add up all those numbers and multiply them by 1.5 or 2 if there’s something particularly high-drawing like an air conditioner or a refrigerator running constantly. 

If you get an answer that doesn’t seem right (say, someone told you it takes 1kW, but their air conditioner uses 2kW), try estimating again with fewer items plugged in—this will give you more realistic results for how much power is being used at any one time throughout each day.

Alternatively, you can consult an expert to do the calculations and give you realistic estimates. Doing so is highly recommended if you’ve never used a generator before and want to power your home or business for a prolonged period. 


I hope that this article has helped you to better understand the risks involved in leaving a generator running unattended.

As a rule, you should not leave your generator running unattended for extended periods. 

However, if you’re only going away for a couple of hours or a few minutes, you can safely leave your generator, provided you take all the necessary safety precautions beforehand.  

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