Carbon monoxide (CO) is an odorless, colorless gas that can be deadly if inhaled. Knowing the signs of a carbon monoxide leak and detecting high levels early is crucial to protect yourself and your family. This comprehensive guide will provide information on carbon monoxide poisoning, where it comes from, how to recognize symptoms, and most importantly—how to detect dangerous levels in your home before it becomes a life-threatening emergency.
What is Carbon Monoxide?
Carbon monoxide (CO) is a combustible gas that contains one carbon atom and one oxygen atom. It is an odorless, colorless, and tasteless gas that is slightly lighter than air. Carbon monoxide is produced from the incomplete combustion of fuels containing carbon such as gasoline, natural gas, oil, propane, coal, and wood. When these fuels burn with an insufficient oxygen supply, CO is produced instead of carbon dioxide (CO2).
Sources of CO in the home include gas-fired appliances like furnaces, water heaters, space heaters, generators, and stoves. It can also come from fireplaces, charcoal grills, and vehicles running in attached garages. Essentially, any fuel-burning device that is malfunctioning, improperly installed, or not properly ventilated can leak dangerous levels of carbon monoxide into your home.
How Carbon Monoxide Affects the Body
When you breathe in carbon monoxide, it enters your bloodstream through the lungs. It then binds to hemoglobin, the molecule in red blood cells that carries oxygen throughout your body. The problem is that CO binds to hemoglobin much more readily than oxygen does. When CO occupies the hemoglobin, oxygen cannot bind to it. This prevents oxygen from reaching your tissues and organs.
Carbon monoxide is dangerous because it gives no warning and you cannot see it or smell it. Even at low concentrations like 200 parts per million (ppm), it can cause fatigue, headaches, dizziness, and nausea. At higher concentrations above 400 ppm, it can be fatal within just 1-3 hours of constant exposure. The health impacts of carbon monoxide exposure depend on the concentration in the air and the duration of exposure.
Recognizing the Symptoms of Carbon Monoxide Poisoning
The most common symptoms of CO poisoning to watch out for include:
– Headaches
– Dizziness
– Nausea
– Vomiting
– Fatigue
– Shortness of breath
– Confusion
– Vision problems
– Loss of consciousness
The symptoms are often described as “flu-like.” The tricky thing about CO poisoning is that the symptoms can easily be mistaken for a cold, flu, or feeling under the weather if you do not suspect CO exposure. However, if more than one person in the household experiences these symptoms at the same time or if pets are also displaying signs of distress, that should raise an immediate red flag that carbon monoxide could be present.
The highest risk of poisoning is during the winter months when furnaces, fireplaces, and space heaters are in frequent use. However, exposure can happen any time of the year if appliances are not properly maintained. Long-term low-level exposure can also cause chronic health effects down the road. Children, pregnant women, unborn babies, elderly people, and those with pre-existing heart or lung conditions are most vulnerable to CO.
Checking for Signs of a Carbon Monoxide Leak
Here are some warning signs that your home could have a CO leak:
– Black sooty stains around gas stoves or appliances
– Increased moisture inside of windows
– Unusual odors from appliances
– Pilot lights that frequently blow out
– Increased condensation inside of windows
– Excessive rusting on appliances or vents
– Loose or disconnected vent/flue connections
– Yellow or orange flames from any fuel-burning appliance (should be blue)
Many leaks originate from malfunctioning or improperly vented furnaces, hot water heaters, stoves, ovens, and space heaters. But one major source that should not be overlooked is your garage. Never run a car engine, generator, or gas-powered equipment in an attached garage, even with the door open. Always move vehicles outdoors before starting them. The CO emitted can quickly migrate into living areas of your home.
How to Detect Carbon Monoxide
The only way to know if carbon monoxide is present is to use a CO detector (also called a CO alarm). Much like smoke detectors, these devices constantly monitor and measure air quality. There are several types of CO detectors to consider:
Battery-Operated CO Alarms
This is the most basic and affordable option. They run solely on battery power and feature an audible alarm. Once CO reaches dangerous levels, a loud siren will sound to alert you. Models with digital displays also show the concentration of CO in ppm. They do not require professional installation, but batteries must be replaced routinely.
Plug-In CO Alarms
Plug-in models offer a convenient alternative since they do not run on batteries. They plug right into any standard electrical outlet. Put them anywhere you need additional coverage beyond your hard-wired detectors. Just be aware that if you lose power, the detector will not work.
Smart CO Detectors
Smart detectors connect to your home wifi network and send app notifications straight to your smartphone if CO levels become concerning. This allows you to monitor air quality remotely. Many even provide additional features like extreme temperature alerts or integrate with other smart devices.
Hard-Wired (or Interconnected) CO Detectors
These hard-wired models are installed by professionals and connected directly to your home’s electrical system with battery backup. Multiple detectors link together wirelessly. If one detects CO, all alarms will sound in unison. This provides whole-home coverage. They may also have relay capabilities to automatically shut off fuel-burning appliances if needed.
Combination Smoke and CO Detectors
All-in-one detectors monitor for both smoke and carbon monoxide gas. They provide two important safety features with one device. These should only be installed by professionals to avoid potential issues differentiating between smoke and CO alarms.
Low-Level CO Detectors
Standard models alarm once CO reaches dangerous levels of 70-150 ppm. But for those highly sensitive to CO or wanting extra precaution, low-level detectors trigger alerts as early as 10-30 ppm. This can give you advance warning of a potential problem.
Interpreting Your Carbon Monoxide Detector
Understanding what the audible and visual alerts mean on your CO detector is key:
– **No signal:** A silent detector is normal and means CO levels are within the safe 0-30 ppm range.
– **Steady green light:** Indicates the detector is actively monitoring for CO and has power.
– **Flashing red light with no alarm:** Means CO levels are rising between 30-70 ppm. This is a good early warning to ventilate your home.
– **Alarm with flashing red light:** Once the audible alarm sounds with the red flashing light, CO levels have hit the 70-150 ppm danger zone. Take immediate action to get everyone outside to fresh air.
– **Chirping with low battery warning:** Detector batteries need to be replaced right away.
Always refer to the manufacturer’s instructions for your particular model for specifics on the meanings of the alerts. The Consumer Product Safety Commission also recommends taking the following actions based on audible alarms:
– If the alarm signal lasts less than 1 minute, press the reset/silence button and monitor for further readings.
– If the alarm signal lasts 1-3 minutes, call emergency services and evacuate the building.
– If the alarm signal lasts more than 3 minutes, it is likely a malfunction so ventilate the home, turn off fuel-burning appliances and call your fire department.
Never ignore an active CO alarm or silence it without fully investigating the cause. Your safety depends on early notification of dangerous CO accumulation.
Where to Place CO Detectors
For whole-home protection, CO detectors should be installed both upstairs and downstairs in your home. Here are some key recommendations on where to install them:
– Within 10 feet of each bedroom door, with each level of the home having a separate detector.
– Near to (but not directly above) any fuel-burning furnace, water heater or appliance.
– In any frequently-occupied rooms (like office, den, or family room).
– In laundry rooms, garages, and basements if they contain gas appliances.
– Within range of sleeping areas if you spend a lot of time in an attached garage, apartment, or crow’s nest.
– On the ceiling in the middle of the room or 6 inches below the ceiling on a wall.
– At least 3 feet away from appliances and vents (to prevent false alarms).
Hard-wired interconnected detectors also allow for strategic placement to relay alarm signals throughout the home. For example, install them in bedrooms, hallways, living rooms, and garages to cover more ground.
It is recommended to have at least one detector on every level of your home and in, or within range of, every sleeping area for complete safety.
Inspection, Cleaning and Replacement
Like smoke detectors, CO detectors have a limited operational life. Gas sensors degrade over time and alarms must be replaced according to manufacturer’s guidelines, typically after 5-7 years. Here are some best practices for maintenance:
– Test alarms monthly by pressing the test/reset button until the audible alarm sounds. This checks the electronics and battery.
– Vacuum the cover twice a year to remove dust, dirt and debris.
– Replace batteries at least once per year. Mark the install date with a sticker or sharpie.
– Best practice is to replace plug-in and battery-powered detectors every 5 years.
– Hardwired detectors may last up to 7 years, but consult manufacturer guidelines.
– When replacing hard-wired detectors, hire a licensed electrician.
– Never paint CO detectors. Paint can clog the openings and impact functionality.
Proper maintenance helps ensure you receive early warnings of CO and your detectors last a full 5-7 years. Follow manufacturer instructions for cleaning, battery replacement intervals, and required replacement dates.
Preventing Carbon Monoxide Exposure
Here are some key prevention tips beyond having working CO detectors:
– Have all fuel-burning appliances inspected annually by an HVAC technician prior to cold weather.
– Check chimneys and flues for blockages, corrosion, or leaks.
– Keep air intake vents and exhaust vents for appliances clear.
– Open the fresh air intake on your furnace.
– Never run vehicles or gas-powered equipment indoors or in attached garages, even with the door open.
– Generator exhaust should be directed away from windows and doors. Keep generators at least 20 feet away from your home.
– Never use gas stoves/ovens for heating.
– Make sure all inside doors or doors between the garage and living space are sealed properly.
– Do not use any gas-powered appliances if they emit strange smells, smoke, or yellow flames indicating CO.
– Do not use portable flameless chemical heaters indoors which release CO.
– Install UL-approved CO alarms in all required locations. Never ignore alarms.
Following proper maintenance and ventilation guidelines for combustion appliances is the best way to prevent CO leaks. But the only guarantee of staying safe is using CO detectors in strategic spots.
What to Do If Your CO Detector Alarms
If you hear the audible alarm from your CO detector signaling dangerous levels, follow these steps immediately:
1. Evacuate everyone from the home, including pets. Do not waste time ventilating or checking for sources of the gas.
2. Call 911 from outside the home to report the situation. Emergency responders have CO monitors to scan the home and provide medical treatment.
3. Do not re-enter the home until emergency services say it is safe, even if the alarm stops sounding. The CO buildup may only temporarily drop, putting you back in danger.
4. If you start experiencing CO poisoning symptoms like dizziness, nausea, or fainting before you can exit, get as low to the floor as possible and call 911 while crawling to a door or window.
5. If safe to do so, open windows and turn off any appliances you suspect until emergency crews arrive. This may ventilate the area and stop the leak, but only if you can do so without putting yourself at risk of prolonged exposure.
6. Seek prompt medical attention for anyone experiencing symptoms. Be aware that symptoms may persist for weeks or months after CO poisoning.
Do not ignore warnings from your CO detectors, as the gas is undetectable to your senses until it starts impacting your health. When in doubt, get out immediately and call emergency services.
Finding a CO Leak’s Source
Once you are outside following a CO alarm, emergency responders will be able to trace the leak using handheld gas detectors with digital readouts. Appliances like furnaces, hot water heaters, stoves, space heaters, and fireplaces that burn natural gas, propane, oil, wood, or coal will be the first things they investigate and rule out as the source. Vehicles running in an open garage are another likely culprit.
Detectors with CO ppm displays can also help pinpoint areas with high concentrations, guiding professionals toward the leak’s origin. In some cases, a smoke machine is used to trace airflows back to the source. It is extremely challenging for untrained individuals to accurately sniff out a leak on their own, given carbon monoxide’s invisible presence. Calling the fire department gives access to the proper tools and training.
Once the CO source is found, repairs or replacements of malfunctioning appliances will be needed. A qualified technician should perform the work and ensure the equipment is properly ventilated before turning it back on. Any faults in chimneys or flues also need fixing to prevent future accumulation of the lethal gas.
Conclusion
Carbon monoxide poses a real threat because it is odorless, invisible, and tasteless, easily catching victims unaware. Staying vigilant for symptoms, knowing your CO detector’s alerts, properly maintaining appliances, and installing UL-approved CO alarms throughout your home offers the best preventative strategy. If those alarms ever go off, evacuate immediately and let professionals assess and repair the situation. Regularly inspecting your CO detectors ensures they work properly when you need them most. With the right combo of preparedness and alarm technology, you can keep your family safe from the silent killer.