Which Gases Can Trigger a Carbon Monoxide Detector? Best Home Safety Tips 2023

Carbon monoxide detectors are essential safety necessities in your home or work environment. They contain sensors meant to detect increased levels of carbon monoxide in the atmosphere. If the CO levels are above average, the detector will sound an alarm on the potential danger. Sometimes, these alarms can set off upon detecting other gases, a situation called a “false alarm.” So, which gases can trigger a carbon monoxide detector?

Fumes from the following gases can also trigger a carbon monoxide detector:

Which Gases Can Trigger a Carbon Monoxide Detector
Image of Carbon Monoxide Detector
  • Hydrogen sulfide
  • Mercaptan
  • Nitrogen dioxide
  • Hydrogen cyanide
  • Ethyl alcohol
  • Dimethyl sulfide
  • Acetylene
  • Sulfur dioxide
  • Isopropyl alcohol fumes
  • Propane
  • Isopropyl alcohol fumes
  • Methyl alcohol fumes

Carbon monoxide detectors can detect other gases in the atmosphere because they are also electrochemical detectors.

Therefore, while it is safe to promptly leave the house and dial 911 upon the sound of your CO alarm, consider deactivating all the sources where the named gases might have leaked.

Did you know? Carbon monoxide is a colorless, odorless, poisonous gas known as a “silent killer.” It is fatal and dangerous as it can kill people without warning. That is why homeowners and state regulations advise the installation of carbon monoxide detectors in all homes.

How to Prevent Other Gases from Setting Off Your Carbon Monoxide Detector

The sound of a carbon monoxide detector can cause havoc and panic within a household. It is even more frustrating when you can hardly identify why the alarm is beeping.

Luckily, there are ways to minimize the chances of such incidents. As mentioned, other elements, including other gases, can trigger your CO alarm.

The following are ways to prevent other gases from setting off your carbon monoxide detector:

  • Buy the Latest Carbon Monoxide Detector

The world is changing so fast, thanks to the advancement of technologies meant to ease and make life better. Carbon monoxide detectors were not left out!

We recommend buying the latest CO detector as they are programmed with the latest technologies, which are more sophisticated. This especially applies if your smoke detector is about 5-10 years old, as a lot has changed within this period.

The latest detectors sync with the current technological advancements, offering more protection. Most importantly, they will alert you when there are real emergencies, thus reducing the chances of false alarm triggers. 

The advancements in the current detectors will offer you and your loved ones maximum protection while also giving you peace of mind. (You don’t have to worry about a false alarm and wondering why it won’t stop chirping).

  • Replace the Malfunctioned/ Faulty Carbon Monoxide Detector

As your carbon monoxide detector ages, it will likely break down and become more faulty. This can be reflected through unexplainable constant chirping and lighting up, even in the absence of an emergency. Other gases can also trigger the aged CO detector, leading to the chirping.

If your CO detector has such tendencies, it will help if you replace it immediately. Additionally, we recommend replacing it every few years to ensure maximum protection against hazardous gases that could cause fire and other fatal outcomes.

  • Check and Replace the Batteries of Your Carbon Monoxide Detector Whenever Necessary

A carbon monoxide detector with low batteries will likely malfunction, causing unnecessary chirps and light flashing. Therefore, we recommend keeping a close eye on the battery level to prevent your device from malfunctioning. 

If your carbon monoxide detector is battery-powered, please ensure you replace the batteries monthly. Also, install it appropriately, based on your manufacturer’s instructions, to prevent false alarms.

  • Inspect for the Presence of any Loose Wires

It is common for wires to loosen up within a device. This is associated with prolonged use of the detector or if you have been replacing it and moving it to different locations. Such scenarios are unfavorable as they will tamper with the device’s functionality. 

In worst cases, it will cause system problems, leading to the device chirping and beeping unnecessarily. Therefore, you’d want to open your carbon monoxide detector and examine for loose wires. If so, reattach the wires; you might have solved your problem.

Will Sewer Gas Set Off a Carbon Monoxide Detector?

A carbon monoxide detector does not detect sewer gas. This is because the CO detector is designed only to read increased levels of carbon monoxide in the environment. Because of this, carbon monoxide cannot pick up other gases in the sewer gas mixture.

However, some people and research argue that sewage containing more than 500 parts per million of methane may set off an alarm. However, there is a distinct difference between carbon monoxide and methane.

While carbon monoxide is a by-product of incomplete burning fuel, methane is not a by-product. This may explain why the CO detector can only pick up carbon monoxide, not sewer gas. 

Besides, sewer gas is primarily made of methane2. However, it also emits other gases such as carbon dioxide, nitrogen dioxide, sulfur dioxide, and hydrogen sulfide.

Such gases may trigger a malfunctioned carbon monoxide detector. However, you will need a sewer gas detector to alert you to the presence of sewer gas because a CO detector will not serve this problem.

However, most people debate if they really need a sewer gas detector. Unlike carbon monoxide gas, which is scentless and colorless, the human nose can easily smell sewer gas. So, many people wonder, Is my Nose More Sensitive than a Sewer Gas Detector?

The simple answer is yes! The human nose is more sensitive to sewer gas than any ppm gas leak detector. Scientifically, the human nose can detect sewer gas levels as low as 0.001 ppm. On the other hand, a detector worth $100 bucks will only detect amounts as low as one ppm.

Olfactory Fatigue is the process in the human body that reduces the nose’s sensitivity, thus reducing its reliability as an objective detector.

However, you cannot rely on your human nose to sense the sewer gas. This is because it changes its sensitivity upon smelling a rancid smell like sewer gas in the home.

Put, sewer gas is more reliable and effective than the human nose in detecting a sewer leak.

What Are the Symptoms of Sewer Gas Poisoning?

What Other Gases Can Set Off a Carbon Monoxide Detector?
Signs of Carbon Monoxide Poisoning

Sewer gas is best described as a by-product of the breakdown of natural human waste. The gas contains a mixture of hydrogen sulfide and ammonia, among other gases.

The mention of sewer gas is often associated with the smell of rotten eggs. Wondering why? The hydrogen sulfide in the gas mixture gives it this smell.

Inhaling low levels of sewer gas is unlikely to harm your health. However, chronic exposure to the gas will manifest through the symptoms of sewer gas poisoning. Described below are some of the symptoms:

  • Fatigue
  • Headache
  • Stomach upset characterized by vomiting and nausea
  • Dizziness or light-headedness
  • Poor memory and concentration

While Sewer gas exposure and poisoning cases are relatively uncommon, people who work in industrial spaces are more exposed to the gas than others. They will portray symptoms of poisoning, such as:

  • Loss of sense of smell. We mentioned earlier that while the nose is highly sensitive to the smell of sewer gas, it will lose its ability to smell over time, making it an unreliable detector.

A person experiencing sewer gas poisoning will no longer be able to smell the smell of a rotten egg.

  • One will experience irritation in the throat, mouth, and lungs
  • One will also develop pink eye as a result of eye irritation
  • One may start experiencing seizures
  • One may fall into a coma.
  • In extreme cases, sewer gas poisoning will lead to a potential loss of life.

Anything that threatens human life is a cause for concern. Therefore, most people often question how one can get diagnosed as suffering from sewer gas poisoning.

However, the Centers for Disease Control and Prevention asserts that no blood test would determine whether one is exposed to sewer poisoning.

However, you can self-diagnose if you notice the smell of sewer gas, show symptoms of exposure to the gas, or have a sewer gas leak in your home or workplace.

It is essential to know what to do if you notice you are experiencing sewer gas poisoning. So, What’s the treatment for Sewer Gas Exposure?

Once you notice a mild exposure to a sewer gas leak, you will need to air out the house promptly, then call a licensed and qualified professional to inspect and fix the source of the leak.

Also, check all the floor drains, toilets, and cents to ascertain that nothing is cracked, clogged, blocked, or loose.

Once you identify the source of the leak, call a plumbing expert and ensure that your drains and plumbing air vents are clean. Also, move to a place with fresh air to reduce the poisoning symptoms.

However, if exposed to higher levels of sewer poisoning, you should immediately seek medical attention.

REMINDER: Symptoms of high exposure to sewer gas include Dizziness, nausea, and breathing difficulties, among others mentioned in the article.

How Dangerous Is Sewer Gas to Your Home?

Sewer gas contains a complex mixture of gases. Some of these gases are deemed highly hazardous

to human life. The primary components of this gas include; ammonia, hydrogen sulfide, methane, and carbon dioxide.

The sewer gas is not so dangerous to human life, especially if exposed in small amounts. However, its components increase the level of toxicity when exposed to high levels

Hydrogen sulfide, a primary component of sewer gas, is considered toxic to the body’s oxygen systems. Hydrogen sulfide may cause adverse symptoms, organ damage, and fatalities like death if inhaled in high amounts.

Ammonia, also present in sewer gas, is famous for its ability to clean chemicals such as Windex. It also has a distinctive, unpleasant odor.

Now, ammonia will cause eye, nose, and throat irritation when exposed to humans. It becomes more toxic if exposed at higher levels, as it can cause organ damage and even death.

Methane and carbon dioxide, present in sewer gas, are considered nontoxic greenhouse gases.

However, they are highly volatile (flammable) it exposed in high amounts. Ammonia is equally highly flammable. Therefore, the three gases combined can contribute to a deadly fire hazard if exposed to high levels.

How Do You Check Your House for Sewer Gas?

Sewer gas backing up into your house can be a severe problem, not just because of the distinctive smell but because of the negative health implications it can cause you.

While you always need to call in a plumber in case of a sewer gas leakage, not all gas backups are serious. You can quickly solve some if you can identify or check your house for leakage.

The following are some of the most common causes of sewer gas leakage in your house:

  • Water Traps

Otherwise known as P-traps or S-traps, water traps are often found near floor drains and laundry tubs. They can also be found below the sink in your house. Their function involves trapping water inside the curve and preventing the gas from moving back into the house.

Like any other appliance, it will likely dry up if you don’t use the water trap as often. They can also dry up if there’s a leak somewhere before the trap.

A dry trap would create a breeding ground for the sewer gas to move into the house.

Therefore, if you notice the smell of sewer gas, check the areas below the sink, the laundry tub, and the floor drain to determine the source of the leakage.

If this is the problem, there are two things you can do:

a.) If you notice the sink produces the sewer gas smell, run the water for a few seconds, and voila! You will have restored your trap.

b.) Pour a pitcher of water down the drain if you suspect the smell is coming from the floor

drain. The water, like in the sink, will restore its normal functioning.

  • Missing Clean-Out Plugs

Inspect the clean-out plugs for your house traps or any other mainline traps. Clean-out plugs are often used as access points in the main sewer lines, often constructed at the foundation of the walls.

The main lines are snaked out through the clean-out plugs, barring the gases from moving into your house.

The clean-out lines are also designed to facilitate clog removal and are capped to prevent sewer gas from escaping into your house. If you notice one of the clean-out lines missing or broken, it could contribute to the sewer gas smell in your house.

The solution is to replace the clean-out plug. You can purchase it from your favorite local hardware store.

  • Bad Wax Ring In The Toilet

You will notice a wax ring between the toilet flange and its base. The wax ring is specially made to

provide an airtight or watertight seal.

The wax ring can sometimes malfunction, leak, or compromise, leading to sewer gas penetrating your home.

Therefore, if you notice your toilet’s wax ring malfunctioning, consider replacing it to solve the problem.

There are more serious causes of sewer gas leakage in your house. While you can identify the source, hiring a qualified technician to fix the problem is vital, as it is more extensive and expensive.

Described below are some of the complex problems causing sewer gas leakage in your house:

  • Sewer or Septic Pipe Leaks

Sewer or septic pipe leaks are harder to diagnose and even harder to repair, so they demand an expert’s attention.

If you notice your toilet gurgling and the drains are slow (often preceded by the rotten egg smell of sewer gas), it could indicate a sewer line leak.

NOTE: Sewer leaks could be caused by improperly placed pipes or vents. Cracks in the foundation of your septic pipes could also lead to gas seeping into your house.

  • Loose Connections

Loose Connections in the sewer lines and vent pipes allow pungent gases to penetrate your home.

This mostly happens inside the ceiling or a wall. Therefore, correcting the damage by yourself can be challenging. It would be best to hire an expert to do it.

  • Loose Toilets

Toilets are crucial integral parts of your house’s sewage system. They can emit sewer gas if they are not tightly fitted into the sewer lines.

  • Cracked Pipes

Check if your house has a cracked, degraded, or broken pipe to identify if it’s the source of the sewer gas smell in your house.

The sewer system pipes in your house are meant to protect your home from exposure to the by-products of human waste. If they are cracked, the sewer gas will penetrate your house.

Now that we can identify sewer gas in our homes, can we do anything to prevent it? Certainly! They say prevention is better than cure. That’s why learning the preventive measures for sewer gas leakage is crucial. Let’s look at them!

Preventive Measures

  • Ensure that There is Water in all the Traps

We’ve mentioned that dry traps significantly contribute to sewer gas leakage into your house. You can prevent this nuisance by first locating all the Traps in your household, from the floor to under the sink

or toilet, or the wall.

Please consider the least used traps and ensure they maintain water levels. The least used traps are more prone to drying than the frequently used ones.

Also, consider pouring several tablespoons of vegetable oil into the water for rarely used traps. This will slow down the evaporation process.

  • Regularly Clean Your Drains

Dirt, dust, debris, hair, and toys, among other elements, will likely clog up your drains. This contributes to the emission of sewer gas into your home.

Clean your drains from such elements and particles by removing the stopper and cleaning the debris.

After setting the stopper aside, bend a hook at the end of the wire and stick it down the drain. Use the hook to remove and dispose of the debris in the trash. Repeat this process as often as possible until there is no debris left.

Pour four to five gallons of hot water into the drain and replace the stop. The water should be hot enough but not boiling. Replace the stopper after you are done.

Note: The drain line can be much longer than the hook, and a small hook may not reach all the dirt in your drain. If so, consider hiring a professional to snake the drain.

  • Ensure the Vent Stack is Free from Debris

The pipe that sticks out of your roof is described as the vent pipe. Ensure that it is free from debris and


If trees with branches hang directly over the vent pipe, you will likely deal with the debris problem. If the trees don’t hang over, you won’t have to deal with clearing the stack.

The trees or other features will drop debris into your vent pipe, thus contributing to its clogging. If you have them around your house, consider hiring professionals to do semi-regular cleanings.

Can Mold Set Off a Carbon Monoxide Detector?

Most people take safety measures with smoke and carbon detectors in their homes. However, very few people consider looking out for mold despite the unpleasant effects it may pose.

Molds grow in moist areas, such as roof leaks, windows, or pipes.

Moisture can also occur in the event of excessive flooding.

Moisture is considered one of the most notorious causes of false alarms in carbon monoxide detectors.

You can hardly mention mold without involving moisture. Therefore, excess mold can trigger a false alarm from a CO detector due to the excess moisture surrounding its growth. That is why you are always advised to install the CO detectors away from moisture.

The moisture from the mold may cause unnecessary chirping or beeping of your carbon monoxide detector, which can be nerve-wracking. For this reason, you’d want to do everything possible to prevent mold growth in your home. Here is what you can do:

  • Maintain low levels of humidity.

Prevent mold growth by keeping your home’s humidity level at least 50% daily. An air conditioner or a humidifier will help keep the humidity levels as low as possible.

You can also purchase a meter to monitor the humidity levels in your home. Note that humidity levels change throughout the day; therefore, consider checking them more than once daily.

  • Ensure That Your Home Has a Free Flow of Air

Depending on your area, the weather can be extremely hot, which might limit the free flow of air. An exhaust fan that vents outside your kitchen and bathroom will help in such a situation. Also, ensure that your clothes dryer vents outside your home.

  • Fix any Leaks in Your Home

Moisture from water is one of the significant factors for the growth of molds. Minimize the chances of its growth by fixing leaks on your home’s roof, walls, or plumbing.

  • Clean up Immediately after Flooding

Ensure that you clean and dry out your home entirely and quickly. Do this between 24 and 48 hours after a flood. Molds are bound to grow after a flooding crisis since the moisture from the flood water is a conducive environment for their growth.

  • Use Mold Inhibitors in Paints

Molds will grow on your painted surface, especially if it did not cure well or if exposed to natural weather elements. You can solve this by adding mold inhibitors to your paint before painting. You can purchase them from paint and home improvement stores.

  • Replace Carpets and Upholstery that Take a Long to Dry up

Ensure that you remove or replace soaked carpets and upholstery that were soaked and did not dry right away. Avoid using carpets in areas like the bathroom or basement, as they contain a lot of moisture.

NOTE: There is a wide range of molds. Some appear like spots, and they come in different colors. They mostly smell musty. The Centers for Disease Control and Prevention recommends immediately removing mold once you spot it growing in your home.

They further recommend cleaning and fixing the moisture problem to prevent it from growing further in your surroundings. You will need household products such as soap and water or a bleach solution containing less than a cup of laundry bleach in one gallon of water.

Additionally, mold poses different health effects to people, including a stuffy nose, sore throat, coughing and wheezing, burning eyes, or a skin rash.

People with asthma or allergies to mold experience severe effects. Mold infections may also worsen the symptoms of those with low immunity and chronic lung complications.

Can Humidity Set Off Carbon Monoxide Detector?

A carbon monoxide detector is designed to go off upon excess carbon monoxide levels. However, the beeping of this detector does not always indicate the presence of CO in the atmosphere.

Moisture, low battery levels, and the device reaching its end are some causes that trigger a carbon monoxide alarm. 

Humidity also contributes to this list. High humidity in the atmosphere would trigger a carbon monoxide detector. Humidity often collects moisture on and around the carbon monoxide sensors, leading to a false alarm, which may seem like a defect.

However, contrary to popular opinion, it is a safety feature. The detector alerts you to changes in humidity levels, saving you the trouble and inconvenience of false alarms.

Also, high humidity levels will cause the sensor to corrode, leading to a false alarm from the CO detector.

To solve this issue, homeowners are encouraged to keep humidity at a minimum of 30-50%. You can do this by using a dehumidifier and opening windows and doors to enhance the proper circulation of air. You also need to know the sources of humidity to prevent false alarms in the future.

CAUTION: Turning off a carbon monoxide detector to prevent the constant chirping and beeping is not the best idea. You must promptly open the windows and doors, leave the potentially risky area, and call 911. The CO gas is odorless, colorless, and extremely dangerous when inhaled at high levels. It can cause slight headaches, Dizziness, nausea, and death.

Final Thoughts

A carbon monoxide detector can be triggered by elements other than the CO levels in the atmosphere. These elements include dust, insects, moisture, and humidity, among other elements. Even so, let’s look at…

Which Gases Can Trigger a Carbon Monoxide Detector

Fumes from gases such as Hydrogen sulfide, Mercaptan, Nitrogen dioxide, Hydrogen cyanide, Ethyl alcohol, Dimethyl sulfide, Acetylene, Isopropyl alcohol fumes, Methyl alcohol fumes, Sulfur dioxide, and propane can trigger carbon monoxide detectors.

Replacing the batteries, buying the latest brand, and fixing loosened wires will help prevent other gases from setting off your carbon monoxide alarm.

Lastly, sewer gas will not set off a carbon monoxide alarm since the gas in the mixture is quite different from carbon monoxide. CO detectors are specifically designed to detect carbon monoxide in the atmosphere; therefore, sewer gas would not set it off.

You can learn much more about a carbon monoxide detector as it is a safety necessity in your home. Let us know what more you would like to know about the detector in the comment section. I hope the article was informative😊

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