Indoor Air Corner: Source Control
By Christine G. Crocker, Executive Director, Maine Indoor Air Quality Council
THE ONGOING COVID-19 GLOBAL pandemic has underscored a critical fact that those of us in the building and environmental health industry have known for a long time: The air indoors can be significantly more polluted than the air outdoors. Even before the pandemic closed schools and workplaces, indoors—at home—was still where we all spent most of our time. And, because exposures to indoor pollutants can be much greater than exposures to outdoor pollutants, the concern for the risks to our health from so much time spent indoors is real.
Two of the primary causes of indoor air quality problems are (1) indoor pollutant sources that release gases or particles into the air, and (2) excessive moisture/ humidity levels that can lead to mold and bacterial growth, as well as mechanical/structural systems failures.
The most effective strategy to improve indoor air quality in homes is to practice source control. Source control is the process of eliminating a pollutant at its source, followed by reducing or managing the individual sources of pollution and their emissions.
How to implement source control in your home
Step 1: Eliminate
Keeping pollutants out of the indoor environment is the primary means to prevent the risk of exposure to them. If it isn’t there, it cannot hurt you. Examples of pollutant elimination in your home can include:
Choosing furnishings and products with the lowest gas and vapor emissions. Homes today are loaded with furniture, carpeting and coatings that release chemicals into the indoor air. Avoid pressed wood products and products with flame and stain retardants, and always use low-VOC paints and finishes.
Choosing electric or induction cooktops over gas cooktops.
Avoiding pesticides by practicing more natural pest control techniques. Stuff copper mesh into foundation cracks to deter mice; use traps instead of chemicals; keep your home clean and dry to make it less attractive to insects.
Switching to more natural cleaning products. Soap, water, vinegar and baking soda are excellent options.
Going fragrance free. Avoid artificial scents in laundry detergents, cleaning products and air fresheners.
Maintaining your indoor humidity in the range of 30–50% to prevent mold and bacterial growth indoors.
Step 2: Reduce and manage
Sometimes, completely eliminating a pollutant from the indoor environment just isn’t possible. Reduce and manage the pollutant source when elimination of the pollutant is not an option. Examples include:
Ventilate! Ventilation provides a pathway for pollutants that find their way indoors to leave your home before they can make you sick. Open windows, use window fans or install a balanced heat or energy recovery ventilation system to bring fresh air into your home and exhaust out pollutants. Install a properly sized range hood that is vented to the outdoors rather than recirculated indoors. Use properly sized bathroom fans that vent to the outdoors to remove odors and excess moisture from showers and baths.
Test the air and the water (if you have a well) in your home for radon and install systems to reduce radon to acceptable levels if needed.
Filter the indoor air to capture dust, pollen, allergens, mold spores, pet dander, smoke, viruses and bacteria and other small particles.
Carefully weigh the value of a product, appliance or system against the risk of its use.
Always follow the label instructions for application of all chemical products used indoors.
Properly store and ventilate hazardous materials and dispose of unused products to limit exposures.
To limit exposure, schedule use of contaminants at times when people aren’t around
For more information about indoor air quality in your home, visit Maine Indoor Air Quality Council’s website.
This article appeared in the Fall/Winter 2021 edition of Green & Healthy Maine HOMES. Subscribe today!