Where should a natural gas detector be placed?

Author: Conner Bosco I  |  Last update: Sunday, June 21, 2026

Propane and gasoline gases have a higher density and are heavier than air, which means having a gas detection near the floor is most beneficial. Lower-density gases such as natural gas are lighter than air and are known to collect near the ceiling of a building.

Where should you put a natural gas detector?

A natural gas alarm should be installed indoors in any room that has a gas-fueled appliance. This can include a stove, furnace, water heater, gas fireplace, or a gas dryer. It should be installed on the wall, within 12 inches from the ceiling.

Should natural gas detector be low or high?

While leaking in their liquid forms, toxic compounds can flow downwards and spread into the lowest areas. The detectors should be installed at low levels (1 to 3 feet) above ground level.

What height should a natural gas detector be mounted?

Gases with a similar density to air, like carbon monoxide, should be detected within the “breathing zone,” which is typically between 4 to 6 feet (1.2 to 1.8 meters) from the floor—where most people breathe.

Does natural gas sink or rise?

Natural gas is lighter than air, so it will rise and disperse if allowed to vent freely. Although rare, natural gas leaks can be dangerous and result in fire, explosions, injury or death. If you suspect a leak, call 1-800-ALLIANT (800-255-4268) immediately.

What Most Homeowners Don’t Know About Carbon Monoxide Detectors

Does natural gas travel up or down?

In conventional natural gas deposits, the natural gas generally flows easily up through wells to the surface.

What is the safe distance from a gas leak?

Don't Panic, act quickly. Immediately exit the building and move at least 350 feet away. Once you are at a safe distance, call PSE&G at 1-800-880-PSEG (7734) or 911 to report a potential gas leak.

How many gas detectors do I need?

It is best to install a gas detector in every room where gas-consuming appliances are installed.

Is natural gas lighter or heavier than air?

Natural gas is lighter than air and rapidly dissipates into the air when it is released. When natural gas burns, a high-temperature blue flame is produced and complete combustion takes place producing only water vapor and carbon dioxide. It has a heating value of about 1000 BTUs per cubic foot.

What kind of detector do I need for natural gas?

Detector Options

Some manufacturers of carbon monoxide detectors offer combination or 3-in-1 detectors to alert when carbon monoxide or an explosive gas such as natural gas or propane is detected.

Do I really need a natural gas detector?

You can choose to not have the natural gas detector installed. However, the detector can provide valuable early warning of a gas leak emergency before it develops into a more serious situation, possibly involving a fire or an explosion. This could result in property damage, serious injuries, or death.

What is the set point of a gas detector?

Combustible gas detection systems are typically arranged to signal an alarm at two different levels of gas concentration. The system could activate output alarm devices and also signal that a specific level of combustible gas exists. Two common alarm set points are 20% LEL and 40% LEL.

Can you smell a natural gas leak?

If you smell a sulfur or rotten-egg-like odor, you could have a gas leak. Natural gas is naturally colorless and odorless. We add an odorant called mercaptan to natural gas, which gives it a distinctive smell. In some cases, you can also identify natural gas by sight or sound.

Should natural gas detectors be high or low?

Propane and gasoline gases have a higher density and are heavier than air, which means having a gas detection near the floor is most beneficial. Lower-density gases such as natural gas are lighter than air and are known to collect near the ceiling of a building.

What is the mounting height for a CH4 sensor?

Methane (CH4) gas is lighter than air, mounting height for Methane (CH4) gas detector is 0.2 meter below ceiling.

Where should a carbon monoxide and gas detector be placed?

The International Association of Fire Chiefs recommends a carbon monoxide detector on every floor of your home, including the basement. A detector should be located within 10 feet of each bedroom door and there should be one near or over any attached garage. Each detector should be replaced every five to six years.

Do natural gas fumes rise or fall?

Natural gas is much lighter than air so when it is released into the air it rises quickly and dissipates outside. The mercaptan is heavier though so it can often sink and hang closer to the surface. This difference is important to why under certain weather conditions you might smell gas.

Will a carbon monoxide detector detect natural gas?

CO can be released by faulty fuel-burning appliances, such as gas stoves, boilers, and fire places. Carbon monoxide detectors will not detect gas leaks involving the natural gas (NG) or liquefied petroleum gas (LPG) which fuel household appliances, such as boilers.

Does natural gas go up or down in the air?

Natural gas is always lighter than air, and will rise in a room if allowed to escape from a burner or leaking fitting. On the contrary, propane is heavier than air and will settle in a basement or other low level. Incomplete combustion can occur when the gas mixture is richer than 10%.

Where is the best place to put a gas detector?

Sensors should be located near the floor for gases or vapors three or four times heavier than air. They should be installed near the ceiling or roof to detect lighter-than-air gases.

Where are gas detectors required?

Where a fuel-gas-burning appliance is installed within a dwelling, the gas alarm must be installed in the same room as the appliance. The alarm must be located at least 3 feet, but not more than 10 feet from the appliance, measured horizontally. The gas alarm must be installed on either the ceiling, or a wall.

What is the lifespan of a natural gas detector?

Catalytic Bead gas detectors: Catalytic bead detectors detect combustible gases such as methane or propane. They rely on the combustion of gases on a heated wire to produce a signal. The lifespan of catalytic bead sensors can vary but generally falls within the range of around five years.

What is an acceptable natural gas leak?

The acceptable leak rate does vary depending on whether the source is domestic or commercial, but a leak rate of 0.000 5 m3/h per m3 of space is generally acceptable in well ventilated areas.

Does natural gas go through walls?

Natural gas is colorless and odorless, and it can penetrate walls even if your home or building is not supplied with gas.

What if my house smells like gas but no leak?

If there is a gas smell but no leaks, it could be the lingering propane odor due to poor ventilation or it coming from your neighbor. The dirty sewage system, contaminated well, or rotten garbage (like veggies, dead animals, residual foods, etc.) might also be the source of the smell.

Previous article
How often should you replace kitchen pots and pans?
Next article
Will a space heater turn itself off?