Purifying Indoor Air: Simple Steps To Breathe Easier

Poor indoor air quality can lead to a variety of health issues, including eye and throat irritation, asthma, and even cancer. To limit indoor air pollution, it is important to first identify the sources of pollution, which can include daily activities such as cooking, cleaning, and home improvement projects. Gas stoves, for instance, emit nitrogen dioxide, which can cause breathing problems. Other sources of indoor air pollution include building materials, smoking, cleaning supplies, and furnishings. To improve indoor air quality, one can employ source control by eliminating or reducing the use of certain products, increasing ventilation by opening windows or using exhaust fans, and adopting cleaner technologies and fuels for cooking, heating, and lighting.

Strategies to limit indoor air pollution:

Ventilation: open windows and doors, use fans, or install a ventilation system

Ventilation is key to promoting healthy indoor air. Opening windows and doors is an easy way to encourage a good exchange of indoor and outdoor air. This is known as natural ventilation and is an important factor in improving indoor air quality. Natural ventilation can also help moderate indoor air temperature, which is useful in homes without air-conditioning systems or when power outages limit their use.

However, it is important to carefully evaluate when to use natural ventilation as a method of reducing indoor air pollutants. This is because, in some cases, outdoor sources of pollutants, such as smoke or refuse, may negatively impact indoor air quality. Therefore, it is recommended to open windows and doors when the weather permits and the pollen count is not too high.

Another option is to use fans to increase ventilation. Local bathroom or kitchen fans that exhaust outdoors directly remove contaminants from the room and increase the outdoor air ventilation rate. Window or attic fans can also be used to increase the ventilation rate when the weather is suitable. Whole-house fans are another option, which can replace the air in a home in just a few minutes by pulling air from opened windows, throughout the home, up into the attic, and out of the attic vents. These fans are incredibly efficient and quiet and can help protect against the airborne transmission of COVID-19.

Finally, mechanical means can be used to increase ventilation. This includes the use of outdoor air intakes associated with the heating, ventilation, and air conditioning (HVAC) system. Advanced designs for new homes are starting to add mechanical features that bring outdoor air into the home through the HVAC system. These designs often include energy-efficient heat recovery ventilators to reduce the cost of cooling and heating the outdoor air.

Avoid pollutants: minimise carpeting, use natural cleaning products, and avoid air fresheners

Minimising the use of carpeting is a good step towards limiting indoor air pollution. Carpeting can trap pollutants, such as dust mites, pathogens, and allergens, which can then be released into the air. Removing existing carpeting and opting for alternative flooring choices can improve indoor air quality. When removing carpeting, it is important to address the subfloor, ensuring it is clean, level, and free of cracks or damage.

Using natural cleaning products is another effective way to limit indoor air pollution. Traditional cleaning products can increase indoor air pollution levels due to the release of volatile organic compounds (VOCs) and other harmful chemicals. These can trigger asthma, lower immunity, and cause respiratory issues. Natural alternatives, such as vinegar and water with peppermint oil, or baking soda and lemon, are effective and non-toxic options.

Air fresheners are also a significant contributor to indoor air pollution. They often contain chemicals and biological components that can negatively impact air quality and cause adverse health effects, including irritation to the eyes, nose, and throat, as well as headaches and nausea. Even homemade or natural air fresheners made with essential oils can contain highly concentrated chemicals that may trigger allergic reactions. Instead of using air fresheners, focus on increasing ventilation by opening windows and doors, using fans, or investing in energy-efficient heat recovery ventilators to improve indoor air quality.

Source control: identify and eliminate sources of indoor pollution, such as gas stoves

Source control is the most effective solution for most indoor air quality problems. This involves identifying and eliminating sources of indoor pollution, such as gas stoves. Gas stoves are a major source of indoor air pollution, as they rely on the direct combustion of natural gas, which releases nitrogen dioxide and other hazardous air pollutants, including volatile organic compounds (VOCs) like benzene, hexane, and toluene. These pollutants are linked to various health issues, including respiratory problems, asthma, and cancer.

To eliminate or reduce emissions from gas stoves, consider the following:

Adjustments to Gas Stoves

Firstly, it is important to note that gas stoves can be adjusted to decrease emissions. For example, ensure your gas stove is properly installed and operated, with a properly installed and functional hood or exhaust fan that vents to the outdoors. This can help reduce the concentration of pollutants in your indoor space.

Alternative Cooking Methods

Consider switching to alternative cooking methods that do not produce the same levels of indoor air pollution as gas stoves. Electric stoves, for example, have been found to have significantly lower levels of NO2 than homes with gas stoves. Electric appliances such as electric kettles, slow cookers, pressure cookers, rice cookers, toaster ovens, or microwaves can be used instead of gas stoves and ovens.

Ventilation

While increasing ventilation does not eliminate the source of pollution, it can help reduce the concentration of indoor air pollutants. Opening windows while cooking can improve indoor air quality by promoting a good exchange of indoor and outdoor air. However, it is important to check your local outdoor air quality index before opening windows, as outdoor pollutants can also enter your home. Natural ventilation through windows and doors can also help moderate indoor air temperature, which is beneficial during power outages or when air conditioning systems are unavailable or malfunctioning.

Air Purifiers

Air purifiers can improve indoor air quality by reducing pollutants, but they do not eliminate the source of pollution. Look for air purifiers with a high clean air delivery rate (CADR) that matches the size of your room. Remember to replace the filters regularly, as dirty filters will reduce the effectiveness of the air purifier.

Policy and Advocacy

On a broader scale, policy changes and advocacy can play a role in eliminating sources of indoor pollution. Organizations and research groups have been advocating for the regulation of gas stoves and the electrification of buildings to reduce indoor air pollution and protect public health. Supporting and engaging with these initiatives can contribute to long-term solutions for indoor air quality issues.

Air purifiers: use machines with HEPA and activated carbon filters to remove fine particles

Air purifiers are an effective way to improve indoor air quality. They are particularly useful in homes where family members may be vulnerable to the effects of indoor air pollution, such as those with asthma.

When looking for an air purifier, it is important to select one with a High-Efficiency Particulate Air (HEPA) filter. HEPA filters are a type of mechanical air filter that can remove at least 99.97% of dust, pollen, mould, bacteria, and any airborne particles with a size of 0.3 microns. Particles that are larger or smaller are trapped with even higher efficiency. HEPA filters are tested using the most difficult particle size to capture, so their efficiency is rated at a worst-case scenario.

HEPA filters work in three ways to capture airborne particles: impaction, interception, and diffusion. The largest particles, about 0.5 microns and above, are captured by impaction, where they are unable to change course and simply stick to the filter fibres. Particles measuring less than 0.5 microns are captured by interception, where they flow around some fibres but eventually touch and stick to one. Finally, very fine particles measuring below 0.1 microns are slowed by their interactions with atmospheric atoms and molecules and eventually drift into a filter fibre.

In addition to a HEPA filter, air purifiers with activated carbon filters are also effective at trapping pollutants like volatile organic compounds (VOCs), which are often released by paints or cleaning products. The combination of a HEPA filter and an activated carbon filter will ensure that fine particles are removed from the air and that pollutants are trapped.

It is also important to consider the size of the room when purchasing an air purifier. Larger spaces may require bigger machines or multiple air purifiers. Additionally, air purifiers with pre-filters can help to extend the life of the HEPA filter by removing larger particles, allowing the HEPA filter to focus on finer particles. Regular cleaning and maintenance of the air purifier, in accordance with the manufacturer's recommendations, will ensure optimal performance.

Clean air sources: use clean energy sources like biogas, ethanol, and solar power

Household energy, which includes cooking, heating, and lighting, is an essential part of daily life. However, it is also a significant contributor to indoor air pollution, with activities like cooking, cleaning, and home improvement projects releasing pollutants into the home. To limit indoor air pollution, it is crucial to adopt clean energy sources and improve ventilation.

One effective way to reduce indoor air pollution is to use clean energy sources such as biogas, ethanol, and solar power. Biogas, produced from organic matter, offers a cleaner alternative to solid fuels like wood, charcoal, and coal, which release harmful pollutants when burned indoors. Ethanol, a clean-burning fuel, can also minimize the health risks associated with household air pollution.

Solar power is another clean energy source that can be utilized through rooftop solar panels to generate electricity or heat water for various purposes, including bathing, kitchen sanitation, and heating. While solar energy on a small scale has minimal environmental impact, large-scale solar farms occupy significant land areas, often in undesirable locations. Additionally, the disposal of solar panels at the end of their lifespan can lead to the release of toxins.

In addition to biogas, ethanol, and solar power, other clean energy sources, such as electricity, liquefied petroleum gas (LPG), and natural gas, can also be employed to reduce indoor air pollution. These cleaner alternatives to traditional stoves and fuels contribute to improved health outcomes and reduced harmful emissions.

To further enhance indoor air quality, it is important to combine the use of clean energy sources with proper ventilation. Opening windows and doors, utilizing fans, and ensuring strategic placement of windows and insulated walls can help reduce indoor pollutant concentrations.

Frequently asked questions