Homes today require specific strategies to maintain a healthy and comfortable living environment.
Ventilation reduces excess moisture and unhealthy indoor air pollutants. Natural ventilation is a system that moves outdoor air into a building or a room and distributes the air within the building or room. The general purpose of ventilation in buildings is to provide healthy air for breathing by both diluting the pollutants originating in the building and removing the pollutants from it.
Today's homes are thermally conditioned using split ACs. While these mechanical air-conditioning systems provide comfortable temperatures indoors during hot summers, the split ACs are not designed to purge fresh air indoors and throw the stale air outdoors. This naturally makes the air inside stale upon prolonged usage, with high levels of Carbon dioxide which develops as a result of the air exhaled by occupants.
When we think of buying a home, we all too often focus on aesthetic features rather than factors such as the quality of the indoor air. In fact, according to the American Lung Association, 85 percent of Americans didn't realize the air in their homes posed a possible health hazard. While America and other European countries depend on mechanical ventilation and air-conditioning throughout the year, due to harsh weather outside, whereas our weather is pleasant for most parts of the year. Thus, most of us naturally use air-conditioning during hotter months and keep the windows open for the remaining parts of the year.
However, without an appropriately designed and installed natural ventilation system, the benefits of these better-built homes can become liabilities. The good news, however, is that we are becoming increasingly aware of the importance of indoor air quality and its direct relationship to good health. We are seeking better comfort and healthier air.
A properly designed and installed natural ventilation system provides a wide array of benefits not only to the homeowner, but also creates healthier, more comfortable ambient environment.
Common pollutants from furniture, paints, carpets, textiles, people, pets, combined with excess moisture from poor ventilation, can create an unhealthy environment.
Excess moisture
Too much moisture can contribute to allergy problems and structural damage by encouraging the growth of mold, mildew, bacteria, dust mites, dry rot and insects. Showers, humidity, cooking and people produce large quantities of moisture on a daily basis.
Common household chemicals and pollutants
Particles
Tobacco smoke
A health risk to smokers and nonsmokers alike – children are especially at risk.
Combustion products
These are produced by fuel-burning heating equipment, gas water heaters and candles. They include but are not limited to:
Control of these factors through proper natural ventilation will enhance the comfort and indoor air quality of the home to help keep the occupants breathing safely. The strategies include:
Sick Building Syndrome
The term "sick building syndrome" (SBS) is used to describe situations in which building occupants experience acute health and comfort effects that appear to be linked to time spent in a building, but no specific illness or cause can be identified. The complaints may be localized in a particular room or an enclosed space of a building and disappear after the occupant leaves the room or enclosed space of the building.
A WHO report claims that atleast 30% of the newly constructed buildings across the world maybe the subject of excessive complaints related to indoor air quality (IAQ). This is a result of the indoor air pollutants and lack of ventilation in the house or any enclosed room. Building occupants complain of symptoms associated with acute discomfort, e.g., headache; eye, nose, or throat irritation; dry cough; dry or itchy skin; dizziness and nausea; difficulty in concentrating; fatigue; and sensitivity to odors. Most of the complainant's report relief soon after leaving the building.
Adequate cross ventilation is essential to flush out the toxic chemicals and dilute the concentrated gases inside the house. Hence, it is very important to keep the doors and windows open to allow fresh air inside the space. Especially in summers when the air inside heats up, designing the rooms for cross ventilation removes the hot air trapped in the rooms due to pressure difference. Thus, understanding the building orientation and studying the wind direction can help in designing the location, size and type of windows to enable good cross-ventilation.
Flushing out Chemical Contaminants from indoor sources
Most indoor air pollution comes from sources inside the building. For example, adhesives, carpeting, upholstery, manufactured wood products, copy machines, pesticides, and cleaning agents may emit volatile organic compounds (VOCs), including formaldehyde. Environmental tobacco smoke contributes high levels of VOCs, other toxic compounds, and respirable particulate matter. Research shows that some VOCs can cause chronic and acute health effects at high concentrations, and some are known carcinogens. Low to moderate levels of multiple VOCs may also produce acute reactions. Combustion products such as carbon monoxide, nitrogen dioxide, as well as respirable particles, can come from unvented kerosene and gas space heaters, woodstoves, fireplaces and gas stoves.
Hence, it is necessary to keep in mind and conduct a building flush out through natural ventilation before occupying a new house and also use environment friendly housekeeping chemicals.
Although there are many cities trying to address issues on the growing PM levels, many air quality investigation studies state that the indoor air is more harmful in most buildings compared to the outdoor air.
