No Exhaust Fans
With Exhaust Fans
I recently purchased another indoor air monitor; an Awair Omni. After installing this monitor in my office I saw that interior CO2 levels were elevated to just above 1000 ppm. The ideal level is 400 ppm to 600 ppm. WHAT??? This is also my home! Yikes – no wonder I feel sleepy and stupid all the time! What’s going on?
The first thing I needed to do was establish an outdoor baseline of CO2. On Sunday my outside baseline was 396 ppm. At the same time, my inside levels we 896 ppm with my office window open. Not good.
Where Does CO2 Come From inside my home?
Lack Of Ventilation In Relation To The Number Of People In A Room Will Cause CO2 Levels To Rise.
The primary way CO2 is generated inside a home is people breathing. CO2 is also created from combustion by burning oil for heat, gas powered heating systems, gas hot water heaters, gas dryers, and gas stoves. These are the common sources; your home may have different points of combustion.
Natural gas is widely used by PG&E to generate electricity as reported in 2018 to the California Energy Commission.
The California wildfires creates additional CO2 as well as carbon black/snoot that impacts our breathing.
The Solution to Pollution is Dilution
That phrase is widely used by environmental consultants to correct a wide variety of indoor contaminants. Ventilation is recommendation for elevated levels of CO2. In commercial spaces with HVACs and elevated interior CO2 levels the recommendation is to run the system with the fan on to reduce CO2 levels. This option may not be available in most older buildings, commercial or residential.
Ventilation is Recommended for Elevated Levels of CO2.
In your residence these actions will lower your interior CO2 levels.
- Open a window, if you can do so without compromising your security.
- Turn on exhaust fans in the kitchen and bath.
Running a HEPA or Carbon-based air purifier will NOT remove CO2.
Living plants will remove a minor amount of CO2, but not enough to return CO2 levels in your office or home to acceptable.
What is a normal CO2 level in a home?
Using CO2 as an indicator of ventilation, ASHRAE has recommended indoor CO2 concentrations be maintained at—or below—1,000 ppm in schools and 800 ppm in offices (see chart below). Clearly the outdoor CO2 concentration directly impacts the indoor concentration.
Carbon dioxide levels and potential health problems are indicated below: 250-350 ppm: background (normal) outdoor air level. 350-1,000 ppm: typical level found in occupied spaces with good air exchange. 1,000-2,000 ppm: level associated with complaints of drowsiness and poor air quality.
250 – 400 ppm: background (normal) outdoor air level. 400 – 1,000 ppm: typical level found in occupied spaces with good air exchange. 1,000 – 2,000 ppm: level associated with complaints of drowsiness and poor air. 2,000 – 5,000 ppm: level associated with headaches, sleepiness, and stagnant, stale, stuffy air.