Perhaps the most common advice you’ll hear about improving indoor air quality is improving the ventilation in the room, home or building. This is to allow more outdoor air to come in and let the indoor air (which may contain VOCs, carbon monoxide and other pollutants) to come out.
But what if the outdoor air also contains significant amounts of pollutants and irritants? This is especially the case in urban and people-dense areas. As a result of our everyday home living and modern commercial activities, urban air quality is not improving. This makes ventilation improvements insufficient or questionable because outdoor air quality is compromised in the first place.
Causes of poor urban air quality
Emissions from vehicles, manufacturers and power generation facilities contribute greatly to declining air quality especially in modern societies. To support our modern lifestyles, more stuff should be produced and more energy should be used. Whether it’s for transport, maintaining a comfortable temperature or just cooking, our present activities (residential or commercial) contribute to declining urban air quality.
But when does outdoor air quality considered low or unacceptable? There are many definitions and the limits are somehow inconsistent among different countries. After all, we also have to consider not just the amounts of pollutants present, but also the climate, geography and demographics. In addition, the number of hours of exposure is also considered. High concentrations of a particular pollutant should only be allowable in short periods.
For instance, the US EPA and National Air Quality Standards (Australia) for carbon monoxide is 9.0 ppm (parts per million) measured over an 8-hour period. But for 35 ppm, the averaging time should only be 1 hour. Moreover, the standard should not be exceeded more than once per year.
Carbon monoxide (CO) – 9.0 ppm (8 hours), 35 ppm (1 hour)
Aside from carbon monoxide, there are also other air pollutants that government and private organisations watch out for. Some of the major pollutants of concern are:
- Nitrogen dioxide
- Sulphur dioxide
The standards are continuously changing and evolving. It’s possible that next year, a new air pollutant will be added to the list and the limits are all revised. This can all happen after researchers gather more data and toxicity levels to humans are updated.
These standards and limits are often set for public health protection. This includes protecting the health of people with vulnerabilities such as young children, asthmatics and the elderly. For example, the inhalation of lead by young children results to permanent adverse health effects to the kids’ brains and nervous systems.
Although the standards set are not yet perfect or optimal, it’s a good start to control the release of dangerous pollutants into the air. As more data are gathered, the standards are still set to be revised. Right now what’s important is to take early steps in controlling harmful emissions.
Effects of poor air quality
Air pollution causes about 7 million deaths a year. This number can rise indefinitely if harmful emissions are left unchecked.
Why does air pollution cause too many fatalities? Pollutants such as nitrogen dioxide and sulphur dioxide may cause respiratory and cardiovascular problems. In fact, air pollution might even affect the incidence and progression of Alzheimer’s and Parkinson’s diseases. The effects of air pollutants get even worse because of our body’s ability to actually absorb these contaminants.
For example, carbon monoxide has 250 times greater affinity to haemoglobin than oxygen. It’s like displacing the oxygen needed by our cells and then the carbon monoxide poisons our bodies. The result is weakness, nausea and loss of consciousness.
Another example is in the effect of sulphur dioxide (SO2). Exposure to high concentrations of sulphur dioxide results to respiratory irritation and dysfunction. Acute airway obstruction may happen because sulphur dioxide may dissolve into sulphite and bisulphite, which can be both easily distributed and absorbed by the body.
Nitrogen dioxide also presents serious toxicological problems. Eyes, nose and throat irritation are the common results of nitrogen dioxide exposure at high enough levels. At extreme levels, chest pain and pulmonary oedema may even result.
It’s just a few examples that show how vulnerable our respiratory system is against major air pollutants. After all, it’s just only recently that lead, sulphur dioxide and nitrogen dioxide are present in significant amounts in human communities. Because of our modern and industrialised living, we’ve been slowly making our environments inhospitable to humans. The effects are even compounded because polluted areas often have high population densities.
What about indoor air quality?
Outdoor air is dangerous enough especially in highly urbanised societies. The high concentration of commercial and industrial activities in these areas make the pollutants much more harmful especially to young children, elderly people and others who already have respiratory issues.
It’s also the case about our indoor air quality. After all, one way or another, air from the outside will come inside our dwelling or workplace. Whether it’s through ventilation or infiltration (entry of outdoor air into the building through joints, cracks and other openings), pollutants always find their way into private spaces.
For example, carbon monoxide might be in unusually high concentrations at places near carparks and busy roads. Remember that earlier we discussed how carbon monoxide diminishes the blood’s oxygen carrying capacity (carbon monoxide has 250 times greater affinity). With that reduced capacity, we might experience impaired vision, loss of brain function and loss of consciousness.
Whether we’re in our residential dwelling or in the workplace, often indoor air quality is last on the list when we’re figuring out why we’re unwell. It’s insidious and right now it’s really hard to pinpoint that poor air quality is the main culprit. Often we blame something else (like the food we eat, the heat) for what we’re negatively feeling or experiencing.
Aside from carbon monoxide and other chemical contaminants, microorganisms could be equally harmful as well. For instance, the presence of moulds results to the release of biotoxins and organic metabolites into the air. These cause strong allergic reactions because our bodies can immediately recognise these as threats. Viruses and bacteria also cause serious harm. In fact, bacteria such as Legionella pneumophilia may cause fever, cough, severe pneumonia and even death.
The dangers from microorganisms can be eliminated or reduced with better sanitation and adherence to building standards (e.g. adequate subfloor ventilation, minimising moisture build-up in bathrooms and other areas). However, these are not enough to guarantee an acceptable air quality especially for people susceptible to respiratory infections.
Ventilation improvements still help. Natural ventilation can significantly reduce the concentrations of chemical and biological contaminants inside the dwelling or workplace. We can also tap into “artificial” ventilation because mechanical features can now be added to some modern HVAC systems so these can bring outdoor air into our homes.
Why ventilation improvements are not enough
As discussed earlier, outdoor air also presents some dangers. It’s especially the case if you’re living in a highly urbanised area wherein there’s a high concentration of vehicular and commercial activities.
Also, ventilation may not be enough to bring down the levels of biological and chemical contaminants inside your dwelling or workplace. Up to 90 per cent (or sometimes more) of our time is being spent indoors and most likely, the doors and windows are always closed. This makes many contaminants freely circulate and linger in closed spaces.
As a result, many residents and business owners choose to have ongoing protection against biological agents and chemical contaminants present in the air. For example, the Vectothor Air160 is effective against:
- Microorganisms and other potentially harmful biological agents (including bacteria and viruses such as Q fever, swine flu and whooping cough, pollen, dust mites, mould)
- Carbon monoxide
- Formaldehyde and volatile organic compounds (which may come from paint thinners, moth repellents, air fresheners, glues, copiers/printers, aerosol sprays, automotive products, dry cleaning fluids, petroleum-based products)
The Air160’s Hospital Grade 3M High Air Flow Electrostatic (HAFE) Filter with Antimicrobial Coating allows for effective removal of airborne particles and pollutants. It also uses a Philips UV-C lamp to disinfect the air with Ultraviolet Radiation destroying viruses, bacteria, moulds and other micro-organisms. As the final step, the Air160 also uses a high-performance ioniser to purify and refresh the air.
To better support your ventilation and other efforts to improve indoor air quality, contact us today for more information.