These easy-to-install sensors help you protect your home.
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When it comes to gas leaks, timing is critical: “Because gas leaks are extremely dangerous, they must be addressed immediately,” says Dan DiClerico, Good Housekeeping Institute’s Home Improvement and Outdoor Lab Director. Catching a gas leak right at its onset can help prevent a hazardous scenario from getting worse.
Whether you’re moving into a new house or updating your existing safety and security devices, our experts recommend investing in a high-quality gas leak detector that can detect toxic gases such as methane, propane, carbon monoxide (CO) or radon. Here, our pros narrow down the best gas leak detectors to help keep you, your family and your home safe.
The Nighthawk does it all with the ability to detect combustible gases like methane and propane as well as carbon monoxide (CO). "I especially like the built-in extension cord, which lets you plug the device into a low outlet but also mount it higher, where natural gas and carbon monoxide gas leaks rise," says DiClerico.
However, he explains that since propane is heavy and sinks, you will need additional units if you're looking to detect all combustible gases simultaneously in your home. He also emphasizes that you'll need to use the extension to reliably detect natural gas.
Our experts like that the unit's digital display makes it easy to see the level of CO, and the peak level of CO detected will be saved in the device’s memory. In addition, the battery backup keeps the unit working even if there is a power outage. We also appreciate the Nighthawk's loud alarm and easily accessible reset button if triggered in error.
While our engineers haven't yet tested the EG Air in the Lab, its value is tough to beat and we love that it includes a 6-foot extension cord so you can plug it into an outlet and mount it near the ceiling to detect natural gas or near the floor to detect propane.
When you first turn it on, the device will take about three minutes to go through a warm-up and self-test sequence. The easy-to-read LED display then registers any concentration of combustible gas, but if the concentration rises above 5%, it triggers a flashing red light and voice alert as well as a loud alarm. "The combination of siren, light and voice alarm provides an added layer of safety, especially in homes with children or the hearing-impaired," says DiClerico.
Amazon reviewers say they felt reassured by the digital display and liked how easy it is to confirm it was working by following the manufacturer’s suggestion of testing the detector with an unlit butane lighter. The downsides are that there is no battery backup in the event of a power outage and it does not detect carbon monoxide.
The battery-powered Denova Detect eliminates the nuisance and eyesore of a dangling cord. Moreover, it can be mounted higher up on the wall, helpful since natural gas is lighter than air and therefore rises towards the ceiling in enclosed spaces. The UL 1484-listed gas detector runs on a pair of lithium batteries with a claimed run-life of 10 years. “The device is easy to set up and mounts to the wall with the provided anchor and screw,” says DiClerico, who is in the middle of an extended field test at his home.
According to the brand, the advanced sensor technology embedded in the detector operates at a very low threshold, meaning you’ll be quickly alerted to any potential gas leaks. We also like that the voice alerts deliver loud, clear warnings in both English and Spanish. Just keep in mind that it's only able to detect methane, so you'll need another detector to pick up on other gases, including carbon monoxide.
Need a quick solution? The lightweight and portable Amprobe GSD600 automatically calibrates when you turn it on and is ready for use in less than a minute. The flexible, handheld probe, which is just over 17 inches long, sucks air through the hose and allows you to check appliances and piping in your house, even in hard-to-reach areas, to pinpoint the precise source of a potential gas leak.
"This is a good option for homeowners who are remodeling and want to make sure their new gas-fired equipment has been properly installed," says DiClerico. A strip of LEDs will light up, and the unit will set off an audible alarm if any gas is detected — additional lights lit on the scale and more frequent beeping indicate a more concentrated presence of gas. The most effective gas leak detectors are sensitive even to minor gas leaks, and this handy device, although pricey, can detect levels as low as 40 parts per million. Keep in mind that it doesn't detect carbon monoxide.
The perfect addition to your smart home, "the Nest Protect is among our top-rated smoke and CO detectors based on its intuitive design and user-friendly interface," says DiClerico. "Plus, Nest is a trusted brand in the smart home category." It's conveniently equipped with voice alerts and informs you of the location of the alarm, while also sending alerts to your phone. That means, in the event of a false alarm (burnt toast, anyone?), you can silence it directly from your phone.
Different light colors on the unit let you know if the device is working or if there is a possible problem or an emergency. Also unique is that a motion detector triggers it to softly light up as you walk underneath it in the dark, so it also functions as a night light (you get to choose the level of light). The unit is battery-powered or can be hardwired, and our pros love that it syncs wirelessly with other devices. We especially appreciate that no monthly subscription is needed. Though you will need an additional unit that detects other types of gases aside from carbon monoxide.
Digital air monitors are relatively new to the home safety category, but our experts like the blanket protection they provide. One of the best we've tested is the Airthings View Plus — so much so that we awarded it a 2022 Good Housekeeping Home Reno Award.
The battery-powered device monitors carbon dioxide and radon, as well as particulate matter from cooking fumes and airborne chemicals from household cleaners. What the Airthings does not monitor is carbon monoxide, nor is it a replacement for smoke alarms. (Note: Carbon dioxide, or CO2, is a gas that's produced by human breathing, among other sources; it's a good measure of air stuffiness in your home and can cause headaches and dizziness at elevated levels. Meanwhile, carbon monoxide, or CO, is a potentially deadly gas produced by fuel-burning appliances and cars.)
Airthings also works as a home weather station, tracking outside climate conditions like temperature and humidity. The data is sent straight to an app on your phone, enabling users to monitor their homes’ indoor air quality remotely. Our testers found the View Plus easy to set up and view data. “I liked getting air quality alerts on my phone, especially with young kids in the house,” said one tester.
This First Alert alarm detects carbon monoxide (CO) and smoke, which is convenient, but it has two additional features that our experts also value. First, as you may need to have more than one of these alarms installed in your home, they can be wirelessly interconnected in a safety network so that when one is triggered, they will all activate. Second, during the set-up, you can program each device with the name of its location (e.g., basement or kitchen), and when the alarm triggers, the voice alert will tell you the location of the problem. Our experts found set-up easy and we like that one button lets you quickly silence a false alarm or test the unit. It's also worth noting that when the battery is low and needs to be replaced, all devices in the network will sound a warning.
Ideal for RVs and camper vans, this compact propane gas alarm is powered by 12vDC from your vehicle and triggers when it senses a propane gas leak. Our engineers haven't tested it firsthand, but it has many features we look for in low-voltage devices, including straightforward installation, assuming you have experience with basic wiring.
An indicator light changes color to let you know if the device has power, if it has detected a leak or if it needs replacing. The loud alarm can be tested or silenced with a single button, and it'll trigger a second time if the space has not been adequately ventilated and a leak is still detected. If you’re looking for a kit that not only detects a propane leak but shuts off the gas supply too, take a look at MTI's 70 series kit (currently out of stock).
Our team of product analysts, home improvement experts and engineers drew on five decades of combined experience to identify brands with proven track records for reliability and performance. We then zeroed in on the specific products that you're most likely to find in stores and online.
Our engineers spent many hours reviewing each unit's technical data to ensure it meets various industry standards, including UL certification. To test gas leak detectors, we exposed detectors to various gases to ensure that alarms were triggered quickly and effectively. To assess each unit's usability, we evaluated its ease of set-up, the intuitiveness of any companion apps and how easily it integrates with other smart home products (if applicable).
✔️ Type of gas: It’s important to understand which gases can be detected by the device and which won’t be. Some detectors can identify more than one gas and some can detect smoke. But don’t make the incorrect assumption that a CO detector will also detect a natural gas leak: Unless it specifically says it will, it won’t.
✔️ Power source: Make sure the device has an indicator so you know it’s being powered. Our pros advise testing your installed detectors every month and replacing the batteries at least once a year. Pro tip: Choosing to replace them on New Year’s Day is always a good annual reminder. Also, keep in mind when shopping that some devices are sealed units that must be completely replaced when the battery fails.
✔️ Expiration date: Many units are only designed to function effectively for a certain amount of time (e.g., five years, seven years, 10 years). Make a point of replacing the device in advance of the expiration date.
✔️ UL-Listed: For peace of mind and better assurance of functionality and operational safety, look for a gas leak detector with a UL-Listed certification. This indicates that the unit has been tested by and meets the safety standards of the Underwriter Laboratories, a third-party organization that conducts rigorous independent research and analyzes safety data to develop standards to guide the safe, sustainable commercialization of evolving technologies.
✔️ Sensitivity: The greater the sensitivity, the easier it'll be for your gas leak detector to identify the source of the leak. We recommend looking for adjustable sensors.
✔️ App-based alerts: Some devices can send data via an app to your smartphone, via Wi-Fi or Bluetooth, to let you monitor the situation even if you’re not there.
✔️ Smart home integration: If you already have other smart home gadgets, consider a gas leak detector that's compatible so it can easily integrate into your smart home ecosystem and boost your home security even further.
Gas leak detectors come in various shapes and forms, though you'll commonly find stationary devices installed in homes. Our pros recommend this type for their ease of use, effectiveness and ability to detect a range of gases. To help you choose the right gas leak detector for you, we describe key features and differences among different types ahead:
Throughout your home, you may need multiple gas leak detectors, especially if you have more than one bedroom or multiple floors. Though most of the sensors we recommend will operate continuously, usually for years, to alert you if a gas leak is detected, they're not designed to identify the exact source of a leak. Utility companies strongly caution homeowners against searching for the source if they have been alerted to a potential gas leak.
Here are some of the most common offenders to watch out for when it comes to the air in your home:
✔️ Evacuate the house immediately if you notice that rotten egg smell of a potential combustible gas leak (natural gas or propane), and call your gas company from outside the home. Utility companies advise that if you suspect a gas leak in your home, do not attempt to identify the source of the leak.
✔️ If the carbon monoxide detector sounds, ensure everyone (including pets) is accounted for and outside or in a well-ventilated space, and call the local fire department. Let them advise you when it’s safe to reenter the home.
✔️Avoid turning anything on or off. That goes for light switches, appliances, thermostats and even a doorbell. The action of turning something on or off could cause a spark, which could ignite flammable gasses.
✔️ Do not ventilate the home. Let the fire department or utility company try to identify the source of the leak first.
For over 120 years, the Good Housekeeping Institute has provided expert tips and product reviews on all things safety-related for your home, including gas leak detectors.
Contributing Product Reviews Analyst Lynn Redmile originally wrote this guide; she has been evaluating various household products, from robot vacuums to water leak detectors, since 2012. She worked with Dan DiClerico, the director of the Home Improvement & Outdoor Lab, who provided insights into detector technology as well as the maintenance of gas equipment and has been writing about home safety and improvement for more than 20 years.
This guide was most recently updated by GH Institute Product Analyst Olivia Lipski, who covers everything from tech to home, fitness, travel, outdoor and more for GH.
Lynn Redmile (she/her) is a contributing product reviews analyst at the Good Housekeeping Institute, where she's been evaluating nutrition, fitness, beauty, textiles, home, pet, and cleaning products since 2012. She brings over 30 years of data analysis and project management experience to the role.
Olivia (she/her) is a senior reviews writer and analyst at the Good Housekeeping Institute, overseeing product testing and covering tech, travel, home, fitness, parenting, health and more. Since joining GH in 2021, she has continued to leverage her extensive product reviews experience by staying on top of the industry’s latest innovations and helping readers make better buying decisions. Olivia is a graduate of the George Washington University, with a bachelor’s degree in journalism, political science and French, and she holds a master’s degree in communications from Sciences Po Paris.
Having written thousands of product reviews and how-to articles on all aspects of home ownership, from routine maintenance to major renovations, Dan (he/him) brings more than 20 years of industry experience to his role as the director of the Home Improvement & Outdoor Lab at the Good Housekeeping Institute. A one-time roofer and a serial remodeler, Dan can often be found keeping house at his restored Brooklyn brownstone, where he lives with his wife and kids.
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