What to Do About Winter's Dry Indoor Air
The causes of the problem and suggested solutions
When frigid conditions prevail outside, most of us in colder climates worry about how to avoid road hazards or prevent a slip on the ice. It’s easy to forget that the cold, dry indoor air in our homes, while invisible, can be an equal risk to our health and well-being as our outdoor concerns.
Dry eyes can be soothed with over-the-counter drops, and a saline spray solution can ease dry sinus woes in winter. But during these cold months, most people need more tools in their arsenal to combat dry indoor air. Try a two-pronged approach by eliminating the irritants that cause poor indoor air quality in the first place and humidifying your home.
Fending Off Indoor Air Pollutants
Americans, on average, spend 90 percent of their time indoors, according to the Environmental Protection Agency (EPA). In winter, many people, especially those in colder climates, tighten up their homes with insulation, maybe plastic on the windows and other tricks to keep the cold air out and warm air from escaping.
But the lack of fresh air can lead to stale air and the buildup of pollutants in your house, which after an extended period of time could irritate your eyes, nose and throat and make you feel ill. (Visit the EPA's Indoor Air Quality web page to learn about potentially harmful contaminants found in homes.)
It turns out that allowing some of that cold outdoor air in is a better idea, according to Michael Goldberg, a certified industrial hygienist and safety professional with Consulting Engineers & Scientists in Malvern, Pa.
Goldberg says introducing fresh outdoor air through your heating, venting and air conditioning (HVAC) system, opening windows or using a vented exhaust fan during winter months is the best and least expensive way to avoid “sick building syndrome.”
“A small decrease in home energy efficiency is outweighed by the health benefits,” he says.
One method popular in Canada is the installation of a trickle vent — a small screened or slatted opening integrated into a window or door frame that allows passive ventilation while avoiding big drafts.
Still, unless you live in a bubble, some indoor air pollutants are inevitable. Your favorite household cleaning products, that oil painting or furniture refinishing hobby you enjoy, even the constant dander from the furry pet members of your family create an influx of air contaminants, potentially exacerbating allergies and asthma for those in your home.
Evaluate Your Heating Sources
It helps to take care of, and review, your heating methods.
“The biggest mistake homeowners make to worsen indoor air quality is failing to routinely maintain their home heating systems,” Goldberg says. “Customary inspections and maintenance should be performed annually by a HVAC professional, preferably before the first cold nights of late autumn.”
In addition, studies have shown that homes with wood-burning fireplaces and pellet stoves have elevated levels of indoor air pollutants, regardless of whether the system is drafty or airtight. Wood smoke contains many of the same toxic and carcinogenic substances as cigarette smoke, and high-risk individuals with asthma or other respiratory issues should limit their exposure.
If you can’t resist building a warm, cozy fire in winter, burn clean, dry wood in short, hot fires with plenty of air to reduce pollution from smoky or inefficient systems. Or you might consider replacing a wood-burning fireplace with a gas-fueled fireplace.
Plants and Air Purifiers Can Make a Difference
Many physicians recommend bringing live plants into your home to “oxygenate” and purify the indoor air, especially in winter. Choose plants that are safe for children and pets, such as ferns, African violets and spider plants, and disperse them throughout your home.
High-quality essential oils, a popular trend, can also effectively cleanse indoor winter air of viruses. It’s important to first research which oils could be toxic to your pets before you diffuse them.
If members of your household are susceptible to asthma or other sensitivities, an air purifier might be a worthwhile purchase. Growing health consciousness about indoor air quality has created a boom in the air purifier market, which is expected to exceed $29 billion globally by 2021, according to a TechSci research report. Air purifiers can cost between $40 and $900, depending on the space they cover.
However, Goldberg is not convinced these machines are as effective as manufacturers claim. “There’s conflicting information on whether or not air purifiers provide health benefits,” he says. “Instead, try to reduce the source of pollutants by keeping the home clean and well-ventilated.”
If you are interested in giving one a try, a less expensive model typically covers up to 600 square feet of living space, while other models can purify the air of an entire house. Varieties include: HEPA (filtered) purifiers, allergy purifiers, electrostatic purifiers and ionic purifiers, which emit an electrical charge to remove particles from the air. An especially powerful option is an ultraviolet air purifier. You can research and review these options here and find a primer on how they work and what to expect from them.
Humidity: Panacea or Problem?
According to the EPA, ideal indoor air humidity is between 30 percent and 50 percent. You can measure the humidity in your home using an inexpensive hygrometer. The second prong in your combat against dry winter air, humidifying your home, is essential to reach that threshold. Physicians have prescribed humidifiers for millions suffering from bloody noses to dry sinuses. Airborne viruses thrive in dry, indoor air and moisture from a humidifier, much like the effect from a steamy shower, makes it easier to clear mucus in your nose, throat and chest.
“It’s a personal preference to use forced heat or radiator heat, depending on the age or renovations made in your house,” Goldberg says. “Forced air is blown and dries out the home. Humidity is the key factor during winter months and can be added mechanically through the HVAC system or by using portable humidifiers.”
A Safe Humidifier Is a Clean Humidifier
That said, humidifiers are safe and effective only as long as they are cleaned properly. Otherwise they can actually spread mold and unhealthy microbes through their mist.
Steam humidifiers (vaporizers) are inexpensive and can be added to a few rooms in the house. Cool mist humidifiers are safer than steam humidifiers around children and pets because the dispersed air is not hot. Ultrasonic humidifiers use high frequency vibrations to turn water into mist.
Spotting Indoor Air Problems
Problems with your indoor air quality might be obvious when you notice a moldy or musty odor upon entering your home, or they might be more insidious, when frequent bouts of respiratory illness linger all winter among your family members.
Goldberg suggests that indoor air quality should be tested when a contaminant has been identified, or if you or family members experience headaches or respiratory problems related to contamination from a hidden water leak, stored chemicals or a microbial contaminant.
It’s important to stay vigilant about maintaining good home hygiene as a year-round endeavor. But pay special attention when hunkering down during the cold, dry months of winter.