Maintaining indoor air quality is challenging during winter. People who live in cold climates spend extra time inside their homes making air quality even more important. It is a challenge to keep the air in our homes healthy due to reduced ventilation, the use of supplemental heating sources and dry winter air.
Even when the temperature is below freezing, you can have clean, healthy air indoors.
Here are four common winter indoor air quality problems and ways to solve them.
#1: Dealing with dry winter air
Anyone who has spent time in a cold climate knows the feeling of dry, cracked skin and lips. They are also familiar with the extremely unpleasant feeling when the inside of your nose gets dry and cracked. A common misconception is that the warm air pumped out by your furnace is what makes your house dry. In fact, the dryness comes from outside.
A given volume of air holds less moisture at lower temperatures. When the outside temperature is below freezing, that air is very dry. That cold air finds its way into your home. Not even the most modern, well-insulated home is perfectly air-tight and older homes allow cold drafts in through poorly sealed doors and windows. That cold, dry air seeping into your house makes winter indoor air so dry.
Excessively dry air can cause problems beyond dry skin. According to the Cleveland Clinic, a dry nose and throat may increase your chances of getting sick. Your immune system depends on the mucus in your nose to catch germs before they get into your system. Studies have found that low humidity levels make influenza viruses more infectious, while a moderate humidity level of around 40 percent reduces their infectiousness [Noti et al, 2013].
Fortunately, the solution to dry winter air is relatively straightforward. Use a humidifier. You have several options, from a whole-house humidifier to small units that humidify a single room. You can also choose evaporative or ultrasonic varieties of humidifiers. A humidifier will add moisture to the air and reduce dryness of your skin, lips, nose and throat. Just be sure to use a humidistat to prevent the humidity from getting too high, which could lead to mold growth.
Keeping houseplants can improve the air quality in your home to a limited extent. Although plants do remove some pollutants from the air, they do not do so at a high enough rate to significantly impact your winter indoor air quality. However, the plants and the soil they are planted in hold, and gradually release, moisture. In the winter, this can help mitigate low humidity. A regularly watered houseplant may act as a sort of natural humidifier.
#2: Pollutants from wood stoves and other heat sources
Many people use a supplemental heating source to keep their homes warm in winter, like a wood stove or, less commonly, a coal stove. While these can generate a lot of heat, they also generate indoor air pollutants that can cause health problems and even potentially be fatal.
Combustion produces carbon monoxide (CO) as a by-product. CO is a colorless, odorless gas that interferes with your body’s ability to use oxygen. High levels of CO in your home may cause headaches, dizziness, impaired thinking and ultimately death. Your furnace, water heater and even your stove all generate carbon monoxide, but they burn relatively efficiently, creating a smaller amount of CO, and if they are properly installed and maintained, are vented properly to prevent it from building up in your home. Wood stoves do not burn as efficiently, so they produce more CO than your stove, for example. Plus, since you do not use your wood stove all year, there may be hidden maintenance problems you fail to notice. If the chimney or flue is blocked or has become damaged, it may be allowing CO to leak into your home. Therefore, it is important to have your wood stove or fireplace checked by a professional every season. Also make sure you have a working CO detector operating in your house at all times.
Wood stoves and fireplaces also create other pollutants as a result of combustion, including some gaseous pollutants and some particulate pollutants. These can be harmful if inhaled, according to the EPA. Proper ventilation and maintenance can minimize these pollutants by venting them outside the house, but probably can not eliminate them entirely.
#3: Pet dander buildup
Your pets probably spend a lot more time indoors during the winter. If they have built up a thick winter coat of fur, then shedding and pet dander can become a problem. Fur buildup can be a problem even for people who are not allergic to cats or dogs. If someone in the house has pet allergies, all that dander can cause a stuffy nose and itchy, watery eyes. One way to reduce the problem is to brush and groom your pet regularly. Giving them too many baths may cause their skin to overproduce oils, according to the American Kennel Club. Another important way to reduce pet dander build-up is to clean frequently. Wipe down surfaces with a damp cloth and vacuum carpets, rugs and upholstery.
#4: Poor air circulation and ventilation during winter
During the winter, the doors and windows are closed and the storm windows are down. You may even have plastic insulation sealing off the windows. There is still significantly less air circulation than in warmer weather, when you can open a window. One of the basic and best ways to increase indoor air quality is to open a window and let some outdoor air in, since outdoor air almost always has fewer pollutants than indoor air. That is not possible in the winter. The pollutants that are normally in your house get trapped and keep building up. Some of these pollutants might be tobacco smoke, VOCs, unpleasant odors, dust mites or other particles.
One way to deal with this problem is to clean more. Wiping down surfaces, mopping and vacuuming will remove a lot of those pollutants from the places in your house where they settle. This prevents them from getting kicked back into the air again by the air blowing from the furnace or someone walking through a room.
The fact that your furnace will be running frequently during the winter requires regular filter changes. Almost all the air in your house will pass through the furnace, ducts and vents at some point. You may decide to placing a HEPA filter on your furnace, which is designed to remove 99.97 percent of all particles that are 0.3 microns in diameter. It is important to change the furnace filter regularly, as it will become clogged with the particles it captures, reducing its efficiency and possibly recirculating pollutants into the air
Another good way to reduce the particulate pollutants in your home is to clean out the vents if they are clogged with excessive dust or debris. A full duct cleaning is something best handled by professionals who often need special equipment to reach all the ducts. However, you can open the HVAC vents and returns and clean them thoroughly. A lot of dust and pet hair tends to collect in these vents and the section of duct immediately behind them. It is also possible to fit filters to these vents, which will capture even more particulates. However, they need to be cleaned or changed regularly. If the vents or returns get clogged, it can reduce the efficiency of your HVAC system.
How an air purifier can improve winter air quality
The many factors that worsen indoor air quality during winter make an air purifier an excellent option. Reduced ventilation and access to outside air take away many of the usual ways to improve indoor air quality. An air purifier allows you to remove pollutants such as dust and dust mites, pet dander and other allergens and VOCs from wood or tobacco smoke. There are several air purifier technologies available, each of them with strengths and weaknesses. An air purifier that is capable of removing particulate pollution as well as VOCs can improve your winter indoor air quality. Unlike traditional air purification technology that solely trap particles, the Molekule PECO technology destroys common indoor air pollutants like allergens and VOCs.
Please note that an air purifier can not be counted on to remove carbon monoxide from the air in your home. Even if you use an air purifier, you should keep a carbon monoxide detector operating at all times.