The weather outside may be frightful, but the air inside could easily be worse. For people who work in commercial, institutional and industrial buildings, winter can be hazardous. No, not driving to and from work on snowy, slippery roads, but breathing the air once they arrive. Many commercial buildings in the U.S. have poor Indoor Air Quality, especially during the winter months.
Why does indoor air quality get worse in winter? Because in order to keep the cold out and energy costs down, we’ve made buildings increasingly airtight with improved insulation and high-efficiency windows and doors. Reducing the amount of warm air escaping to the outdoors and the amount of cold outside air getting in means building occupants are breathing a greater amount of recirculated – not fresh – air. In addition to heat, that air carries dust, pollen, mold spores, pollutants and odors. As these hitchhikers continuously cycle through the building throughout the winter, the concentration of contaminants in the air increases.
While some health effects caused by bad air are immediate, short-term and treatable, long-term exposure can produce more serious conditions. According to the U.S. Environmental Protection Agency, poor winter indoor air quality can aggravate respiratory conditions like asthma and increase a person’s risk of developing pneumonia and other upper respiratory problems. Long-term exposure to indoor airborne contaminants can also cause cancer and increase the risk of heart disease.
Poor winter indoor air quality can also be costly to a business. There are the medical expenses of sick workers to cover and poor indoor air quality can also increase absences and significantly decrease worker productivity. Even if a suffering worker clocks in, no one is at peak performance with watery eyes and a runny nose.
Fortunately indoor air quality can be improved, even in winter. Here are some ways to clear the air in a commercial or industrial building:
- Keep it clean. Be sure to keep all areas of the building as clean as possible, especially in the winter. Dusting safely while wearing an air-filtering mask along with regular and frequent vacuuming will reduce airborne pollutants like mold, pollen and dust mites. Use a vacuum with a HEPA filter to avoid blowing dust back into the air. Use non-toxic cleaning products whenever possible. If harsh chemicals are necessary, make sure the area being cleaned is well ventilated to prevent fumes from lingering in the room and on surfaces cleaned with them.
- Check the ducts. Dirt and debris can build up in the ductwork and transfer to indoor air. Inspect air ducts frequently and if you haven’t already, consider having the ducts cleaned and then sealed.
- Pay attention to the air filters. HVAC system air filters are the front line of defense against indoor air pollutants, but in order to do the job well, they must be maintained – especially in winter when the heating unit is running almost constantly. Dirty air filters are a major contributor to poor indoor air quality. Check your filters regularly and change them as needed. Make sure that when they are installed, filters are secured tightly to avoid gaps between the filter frame and rack. This reduces bypass air, which can harm indoor air quality by allowing breathable particles to pass through without being filtered.
- Consider upgrading filters. Consult with a commercial HVAC contractor to determine if it is possible and cost effective to switch to filters with a higher MERV, or filtration efficiency, rating. A higher quality filter may increase the capture efficiency for the submicron particles that can cause health problems.
- Control it at the source. As with toxic cleaning solutions, removing other sources of indoor air pollution can greatly improve indoor air quality. Gas emissions from aging equipment, for example, can be reduced with proper maintenance. Sealing or enclosing asbestos is critical. Reducing or eliminating the source of indoor air pollution is more cost effective than increasing ventilation, which can increase energy costs.
- Increase ventilation. An obvious way to reduce bad indoor air is to bring more fresh air into circulation. Signs of poor ventilation include condensation on walls or windows, stuffy air, moldy areas, and dirty heating or cooling equipment as well as odors that are most notable when entering the building from the outside. Be aware of areas where special attention should be paid to ventilation. Without proper ventilation, toxins emitted during painting, sanding, welding or cooking can be distributed throughout the building.
- Consider using an air purifier. Using an air purifier designed for commercial use may be helpful, but keep in mind that some air purifiers only capture particulate matter. Activated carbon filters are needed in order to remove gas, odors and chemicals. Advanced technology enables some new air purifiers to capture and kill even small pathogens like bacteria, viruses, pollen, smoke, animal dander and other pollutants, and some units can purify the air several times every hour. It can be an effective way to help keep the indoor air cleaner during the winter. When considering air purifier technology, keep in mind that it must have the proper capacity to handle the job. This depends on factors such as pollutant levels, sensitivity and room size.
- Install and maintain energy-recovery ventilators. Also known as air-heat exchangers, these systems should bring adequate fresh air into a building to maintain a healthy environment. Air-heat exchangers remove stale, polluted indoor air and replace it with fresh outside air. The best part is that these ventilators do not use extra energy to heat the fresh air. It is heated with energy recovered from the operation of the system. Energy-recovery ventilators also remove excess humidity from the building in summer. They can be operated by humidistats that detect low or high humidity levels.
- Add humidity. It’s not just polluted indoor air that can cause discomfort or illness. The extreme dryness of winter air also contributes. Fan-powered humidifiers blow moisture vapor directly into the heating ducts to increase the moisture content of the air and reduce static electricity. This can help building occupants breathe more comfortably by preventing dry throats and nasal passages. Adding the right amount of humidity to the air also controls dust mites, mold and mildew.
Indoor air quality depends on the length and severity of winter in your geographic area, the age and size of your building, the number of occupants, what processes take place in the facility and how the indoor space is divided. If you have concerns about the indoor air quality, consult with a commercial HVAC contractor for suggestions on how to turn winters on the job into a breath of clean air.