What Are the Signs of Carbon Monoxide Poisoning?

July 9, 2024
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Carbon monoxide poisoning causes hundreds of deaths in the US each year and results in over 100,000 emergency room visits. That makes it one of the biggest potential dangers in a home that has any type of gas-burning appliance. Part of the reason that carbon monoxide is so deadly is that it’s completely odorless and colorless. That means there is no way to detect its presence until you start noticing the symptoms of carbon monoxide exposure. We’ll discuss what the symptoms are and also how you can help protect yourself and your family against carbon monoxide poisoning.

Signs of Carbon Monoxide Poisoning

Carbon monoxide poisoning can set in slowly over a period of several hours. However, if a person breathes in a higher concentration of carbon monoxide, fatal poisoning can occur within just a few minutes. The fact that death can occur so quickly is why it’s essential that you and everyone in your family know how to recognize the symptoms.

The most common symptoms and the ones that usually occur first are a headache, nausea and trouble breathing/shortness of breath. The headache and nausea usually start off somewhat mild but will progressively get worse the more carbon monoxide you continue to breathe in. Moderate to severe exposure also often leads to dizziness, chest pains, weakness or feelings of fatigue, vomiting, confusion, memory problems and difficulties with muscle coordination. If the person doesn’t immediately get outside where they can breathe fresh air, they’ll finally end up losing consciousness and passing away.

The reason that carbon monoxide poisoning occurs is that when you breathe in the gas molecules, they begin taking the place of oxygen in your red blood cells. This results in your body beginning to be starved of oxygen so that you eventually die without immediate treatment.

Why Carbon Monoxide Detectors Are Essential

Any gas-burning appliance can potentially produce carbon monoxide. There is also a risk with fireplaces and pellet stoves since carbon monoxide can be produced when wood burns. Still, the biggest risk generally comes from gas furnaces since they burn much more fuel than other gas appliances. This is why the risk of carbon monoxide poisoning is slightly higher in winter.

The risk of fatal poisoning is also at its highest at night. That’s partly because furnaces tend to run more at night when it’s colder, but the main reason is that the symptoms may not be severe enough to wake a person up. That means you may just lose consciousness and pass away. This is why more than one-third of all deaths from carbon monoxide occur at night when the person is asleep.

The fact that so many fatal cases occur while the victim is sleeping is one of the main reasons why having carbon monoxide detectors or alarms throughout your home is important. It’s also important that the detectors are installed in the right places. The basic rule is that you should have one detector inside every bedroom or near the bedroom door. If the bedrooms aren’t that far apart, you could just put a single detector in the hall. That is as long as it’s no more than 10 to 15 feet away from every bedroom door.

Whether you want to put the detector in the hallway depends on whether there’s a heating supply vent nearby. If carbon monoxide is leaking out of the furnace, it will get circulated by the heating system and flow out of the supply vents. That means it will get pumped out of the supply vents in each bedroom. If there isn’t a vent in the hallway, you’re definitely better off having a detector in every bedroom. That’s because poisoning can potentially happen so quickly that the carbon monoxide may not flow out into the hallway and set off the detector until it’s too late. This is especially the case if everyone sleeps with their bedroom doors closed.

You should also make sure you have one or more detectors on every level of your house. One detector on every level should be sufficient for a smaller house. If your house is larger, you should install at least two for every level and place them on opposite sides of the level. While you can mount all of the detectors on the ceiling, the EPA recommends instead placing them on a wall at around eye level.

The last thing to note is that you should also have an additional detector somewhat near every gas appliance or fireplace. These detectors should be around 15 feet away from the appliance since they could end up producing false alarms if they’re too close.

Most people opt to install battery-powered detectors since they are less expensive and you can easily mount them yourself. Nonetheless, experts recommend instead choosing hard-wired detectors that are connected to your electrical system. The main reason is that every detector is linked together. That means that if one detector goes off, it will immediately set off the alarm so that every detector in the house goes off. Hard-wired units also have batteries so that they’ll still work if the power to your home is out. The batteries provide a failsafe or an added level of protection that should ensure the detectors always go off if carbon monoxide is present in your home.

How Maintaining Gas Appliances Can Lower the Risk of Carbon Monoxide Poisoning

Carbon monoxide is a byproduct that’s sometimes produced when certain carbon-based fuels are burned, including wood, coal, oil and gasoline. Many people wrongly believe that it’s always produced when natural gas or any of these other fuels burn, but this actually isn’t the case. Natural gas burns extremely cleanly and the only byproducts that are produced when it fully combusts are carbon dioxide and water vapor. The only time carbon monoxide is produced is when the flames produced by the burning gas or fuel don’t receive enough oxygen, resulting in incomplete combustion.

The problem is that furnaces and other gas appliances can develop issues that make it so that the natural gas doesn’t fully combust. That is why they can sometimes produce carbon monoxide. This most commonly happens because the gas burners are dirty, but it can also occur for a variety of other reasons. That’s why having your furnace and other gas appliances professionally maintained each year is important since it helps to ensure that the gas fully combusts and no carbon monoxide is produced.

It’s also a good idea to regularly check your furnace throughout the winter to see what color the flames coming off the burners are. Natural gas produces a strong, steady bright blue flame when it combusts fully. If the gas doesn’t fully combust, the burner flames will flicker and be either orange or yellow. If you ever see orange or yellow flames, you should immediately contact an HVAC company to have your furnace inspected and serviced.

Your Trusted Heating and Air Conditioning Experts

Brennan Heating & Air Conditioning has over 35 years of experience providing expert home services in Seattle and the Puget Sound area. We specialize in the full range of heating, air conditioning, plumbing and electrical services. That means you can count on us for indoor air quality, furnace maintenance and repair needs, or if you want to install hard-wired carbon monoxide detectors in your home. For more information or to schedule an appointment, contact us today.

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