Combustibles Gas Leak Detector

Model: FD-91-RED
User Manual: Click Here
Blog Article: Click Here


⚛️ ACCURATE: Sensor made in Japan.
💪 SHOCK: ABS housing can withstand a 10 ft drop.
🌈 DISPLAY: Color LCD with digital ppm.
🌋 USES: Inspectors, technicians, homeowners.
🕵️ TRUSTWORTHY: 1-year warranty.


Gas: Combustibles (methane calibration): 0 - 9999 ppm or 0.00-20.00% LEL
Accuracy: 10% F.S.
Sensor: Figaro semiconducting metal oxide
Response time: < 2 seconds
Warm-up time: 30 seconds
Display: numeric ppm or %LEL and bar graph
Alarm: Visible and audible alarm point @ 500 ppm
Calibration: Zero calibration
Auto-off: after 10 minutes
Dimensions: 6 in x 2.4 in x 1.2 in
Weight: 11 oz
Power: 3 x AAA 1.5V batteries
Operating temperature: 30F - 122F
Working Humidity: 10% - 90% RH
Gooseneck length: 10 in

Combustibles Gas Leak
natural gas leak detector

In the Box?

  • Sensitive Japanese Sensor (Combustibles)
  • 3 x AAA Batteries
  • 10-inch Gooseneck
  • Color English Manual
  • Color LCD Display with PPM Display
  • ABS housing can take a 10ft drop
  • Temperature sensor (C or F)
natural gas leak detector

Best Combustibles Gas Leak Detector

Introducing a highly sensitive Combustibles Gas Leak Detector equipped with the finest Japanese FIGARO gas sensor, designed to detect even the slightest traces of combustible gas leaks such as acetone, acetylene, alcohol, ammonia, benzene, butane, ethanol, gasoline, hexane, methane, naphtha, natural gas, paint thinners, propane, solvents, and hundreds of other combustible gases. This compact and sturdy device can withstand a 10ft drop, making it an ideal choice for both home and industrial use. Perfect for homeowners, plumbers, and HVAC to locate natural gas leaks at gas lines, connections, or appliances. A combustibles gas leak detector is also commonly used in industrial applications such as underground storage tanks, oil rigs, tanks, and silos in the maritime industry for inspectors, utility workers, refinery workers, maintenance engineers, and technicians.

natural gas leak detector

Combustible Gases Detected?

Detectable Gases detected by the Natural Gas Leak detector include: Acetone, Acetylene, Alcohol, Ammonia, Butane, Ethanol, Ethylene Oxide, Gasoline, Hexane, Methane, Naphtha, Natural Gas, Paint Thinners, Propane, and various Solvents.

Who Uses a Combustibles Gas Leak Detector?

Several individuals and professionals use natural gas leak detectors for various purposes. Here are some examples:

Homeowners: Homeowners use natural gas leak detectors to ensure the safety of their homes. These detectors are typically used forgas appliances, such as stoves, water heaters, and furnaces, to detect any gas leaks.

Property Managers: Property managers utilize natural gas leak detectors in residential and commercial buildings to protect the occupants and prevent gas-related accidents. These detectors help ensure compliance with safety regulations and provide prompt detection and response to gas leaks.

Utility Companies: Gas utility companies use natural gas leak detectors to inspect their infrastructure, including pipelines and distribution networks. These detectors assist in locating and identifying gas leaks.

Industrial Facilities: Industries that use natural gas as a fuel source, such as manufacturing plants, power plants, and refineries, employ gas leak detectors to monitor their operations. These detectors help prevent potential explosions, fires, or health hazards caused by gas leaks in industrial settings.

Emergency Response Teams: Firefighters, hazardous material response teams, and other emergency response personnel use natural gas leak detectors during gas leak incidents.

Environmental Agencies: Environmental agencies and regulatory bodies may use natural gas leak detectors to monitor and detect gas leaks in natural gas production, storage, and distribution facilities. This helps ensure compliance with environmental regulations and minimize the impact of gas leaks on the environment.

natural gas leak detector

What about Combustibles Gas Bump Testing?

Ensuring the proper operation of your natural gas leak detector is crucial. To confirm its functionality and build confidence, it is recommended to perform a bump test. This involves exposing the gas leak detector to natural gas or methane bump gas, which is sprayed on the sensor to induce a positive response.

If you do not have methane bump gas, you can simply expose the gas sensor to some stovetop gas to induce and confirm a reaction.

natural gas leak detector

What is Combustible Gas?

Combustible gas is a gas that can be ignited and burned in the presence of oxygen. Common combustible gases include methane, propane, butane, hydrogen, and natural gas. These gases are often used as fuels for heating, cooking, and powering engines. However, they can also be dangerous if not handled properly, as they can cause fires or explosions if they leak or are exposed to a spark or flame.

natural gas leak detector

What Does A Combustible Gas Leak Smell Like?

Many combustible gases have no odor, which can make them difficult to detect. However, for safety reasons, an odorant is often added to these gases to make them easier to detect. For example, natural gas is typically odorless, but a chemical called mercaptan is added to give it a distinct sulfur-like odor. Propane, which is commonly used in grills and other appliances, also has a distinct odor added to it. This odor is often described as a "rotten egg" smell. If you smell gas in your home or workplace, it's important to evacuate the area immediately and contact the appropriate authorities.

How to Detect a Combustible Gas Leak?

If you suspect you have a natural gas leak, you should use a tool such as a Natural Gas Leak Detector.

  • Begin by turning on the Combustibles Gas Leak Detector and allowing it to start operating after the countdown.
  • Next, perform a quick bump test to ensure the analyzer is functional. You can do this by exposing it to some natural gas or propane from your stovetop or other controlled source. The point here is to confirm the Gas Leak Detector is indeed operating.
  • Once you have completed the bump test, take the Gas Leak Detector and scan the area of interest, moving about 2 seconds per inch. Be patient and thorough to ensure you capture any natural gas.
  • Typical areas of leakage occur at gas lines, joints, valves, and fittings, as well as around the gas appliances. Make sure to check these locations.
  • Observe the detector's response. The units have a digital readout in PPM and %LEL so it is very sensitive.
  • If you have confirmed a gas leak, ensure you take appropriate action to maximize safety. This may involve turning off the gas supply, evacuating the area, and contacting a qualified professional or emergency services to address the situation.

How Long Does the Combustibles Gas Sensor Last?

Our Combustibles Gas Leak Detector is equipped with a made-in-Japan solid-state thermal semiconducting metal oxide sensor element. This is good news as these sensors have a much longer lifespan than traditional electrochemical gas sensors. In fact, semiconducting metal oxide sensors can last up to 10 years, whereas electrochemical gas sensors and catalytic gas sensors typically last only 2-3 years.

What are Safe Combustible Gas Levels?

The safe levels of combustible gases depend on the specific gas and the environment in which it is present. In general, the safe levels of combustible gases are expressed as a percentage of the lower explosive limit (LEL) or the upper explosive limit (UEL). The LEL is the minimum concentration of gas in the air that can ignite and cause an explosion, while the UEL is the maximum concentration of gas in the air that can ignite and cause an explosion.

It's important to note that even concentrations of combustible gases below the LEL can be dangerous, as they can still pose a fire hazard and may indicate a gas leak. If you suspect a gas leak, it's important to evacuate the area immediately and contact the appropriate authorities.


A natural gas leak can be dangerous as the combustible natural gas can accumulate creating a flammable and explosive situation.

Methane (CH4) is highly flammable and is explosive when levels are between 5% to 15% volume.

Even if the levels do not increase to explosive levels, OSHA has set the permissible exposure limit for methane at 1,000 parts per million (ppm) as a time-weighted average (TWA) for an 8-hour workday. NIOSH has a recommended exposure limit (REL) of 1,000 ppm for methane as a TWA.

Furthermore, we recommend if you do detect ANY gas leak of a combustible, such as natural gas, it MUST be addressed. Otherwise, the leak can increase and cause a major safety hazard.

Will a Combustibles Gas Leak set off Carbon Monoxide Detector?

No, combustibles will not set off a carbon monoxide (CO) detector. Carbon monoxide detectors are specifically designed to detect and alert occupants to the presence of carbon monoxide gas.

Natural gas, on the other hand, primarily consists of methane (CH4) and no trace of carbon monoxide is within it.

How Should I Store my Combustibles Gas Leak Detector?

To ensure maximum sensor life and accurate measurements upon operation, it is recommended to store the Natural Gas Leak Detector in a moderate environment with a humidity level of 50%RH and a room temperature of approximately 70F. The unit should be kept in the hard waterproof case it was sold with for optimal storage conditions.


  • A combustibles gas leak detector is a device designed to find natural gas leaks along gas lines, connections, and appliances.
  • They help identify and locate potential gas leaks to prevent accidents, fires, or explosions.
  • Combustibles Gas Leak Detectors include combustible sensor components that are sensitive to methane, butane, alcohols, gasoline, diesel, propane, and many other everyday combustible gases and vapors.
  • Combustibles gas leak detectors provide visual and audible alarms to alert users when gas concentrations reach potentially hazardous levels.
  • They are used in various settings, including residential homes, commercial buildings, and industrial facilities, and by professionals such as inspectors, technicians, and emergency response teams.


This article was written by me, Dr. Koz (no ghostwriters and no AI content here!). I am the President of Forensics Detectors (CA, USA). I am also a subject matter expert on gas sensor technology, gas detectors, gas meters, and gas analyzers. I have been designing, building, manufacturing, and testing toxic gas detection systems for over 20 years.... and still love it.


dr Koz