Now that June is here, we’re finally leaving windows open and breathing the best air of the year. Even if you live in a harmlessly small 24,000-people city like Kingston, the air inside your home is almost never as good as the air outside.
According to the government, we spend 90% of our lives indoors. Just how dangerous this is depend on such factors as what heating system we use, how “tight” the house is, whether we smoke, and whether out-gassing of things like formaldehyde is ongoing. The best heating systems from the standpoint of preserving indoor air quality use no oxygen from within the home for combustion and then vent all pollutants to the outside.
A portable kerosene heater fails on both counts, and causes a steady degradation in air quality. At the upper end of the scale are central heating systems, which can do everything right. The very best? Heat pumps, which are absolutely superb.
Another major cause of indoor air pollution is outgassing of noxious chemicals, particularly formaldehyde, from household objects and new construction. Among the worst offenders are particleboard and chipboard found in shelving units, speaker systems and other pressed wood products and some synthetic carpets. Particleboard can release ten times more formaldehyde than exterior-grade plywood. When used as sub-flooring, pressed board gases emanate from the finished floor for months and even years.
Another source of indoor air pollution are the molds, spores and bacteria caused by standing water or periodic wettings. A damp basement will breed these, and all carpets and rugs that directly contact concrete almost automatically retain dampness, which in turn usually generates biological problems. Air conditioners — good machines for alleviating dampness — can be the culprit themselves as they shelter pools of water. These are ideal places for microscopic pathogens to breed. Anytime you smell a moldy odor near an air-conditioner or humidifier, you should automatically open the unit (after unplugging it), clean it out with disinfectant and allow it to dry.
All indoor pollution problems are mitigated — or exacerbated — by the amount of ventilation in the house. Now in summer we generally don’t have to be concerned. And during the rest of the year the average home has a complete change of air each hour simply because houses leak, especially around windows and doors.
But in a “tight” energy-saving house like many frame homes less than 30 years old, it can take four or five hours for one air exchange and serious amounts of pollutants can accumulate.
Since this is “The Night Sky” you might be interested to know that nocturnal outdoor air quality is almost always much better than the daytime version, an effect far more pronounced in large cities. Particulate matter from diesel engine trucks, buses and factories naturally soars during business hours and when commuters are most active. Moreover, tiny airborne water droplets whose presence is revealed by a milky sky color and whose intensity varies with humidity carry pollutants directly into your lungs, and this air is both drier and cleaner at night. You can see why that’s better than whatever’s circulating inside your home since, according to the EPA, 60,000 chemicals are now in common use, especially in construction materials like paint, polyurethane, cleaners, and glues.
So, try to remember to frequently do what you’re already doing this month. Open the window.