Good indoor air quality (IAQ) is not just a COVID-19 issue, however the pandemic has shed significant light on potential airborne transmission of viruses and prevention practices businesses and schools need to implement.
IAQ is impacted by aerosols, which are tiny particles or droplets suspended in the air.
These particles exist everywhere and can be from natural or man-made sources.
Some aerosols are detrimental to human health, especially when inhaled and deposited in the respiratory system.
While more research is underway to understand the aerosol transmission of respiratory viruses like SARS-CoV-2, many in the science community believe these viruses are spread when aerosols are released into the air from an infected person as they speak, cough, sneeze or simply breathe.
Aerosols can be deposited on surfaces and spread through physical transport, such as when an individual touches a contaminated surface and then touches their eyes, nose or mouth.
The advice given around protecting yourself and others from COVID-19 is just as relevant to protecting against all other infectious aerosols and droplets:
Let’s talk about disinfectants in more detail. Yes, disinfectants are a great way to prevent the physical transmission of deposited aerosols and projected droplets, but many disinfectants contain harmful volatile organic compounds (VOCs), depending on exposure.
VOCs are volatile organic compounds that evaporate into the air – like alcohols, phenols, formaldehyde – that may create short-term health effects including eye, ear, nose and throat irritation, headaches and nausea.
Chronic or long-term exposure may lead to liver, kidney and central nervous system damage.
When using disinfectants, only use those approved by the United States Environmental Protection Agency (US EPA).
Disinfectants should only be used in well-ventilated spaces and if possible, where windows can be opened to dissipate the vapors.
Standalone air cleaners containing carbon bed filters can help reduce VOCs in small spaces, but they will need frequent filter changes when high levels of VOCs are present.
Aside from proper personal hygiene, social distancing and disinfectant usage, those individuals in charge of managing offices, schools and other public buildings must implement effective ventilation and air purification tactics.
To improve IAQ to mitigate the risk of hazardous aerosol and VOC transmission:
Keep the ventilation system running and open windows to provide as much outdoor air dilution as possible
If possible, use single pass ventilation so that building air is not recirculated
If some air must be recirculated, filter it using the highest possible minimum efficiency reporting value (MERV) rated filter to deter re-entry of particles
Control humidity to within 40-60% relative humidity (RH)
Use HEPA-filtered air cleaners in designated personal areas
Use only low-emitting materials, furnishings and office equipment
Of course, good IAQ is not just about preventing the transmission of viruses that cause disease like COVID-19. It is also about limiting indoor air pollution to reduce respiratory and cardiovascular related health problems like chronic obstructive pulmonary disease (COPD) and asthma.
people affected by COPD. 3 million die from it each year. This makes it the third leading cause of death worldwide.
people affected by asthma, making it the most common chronic disease of childhood. It affects 14% of children globally – and rising.
And as we now know, viruses like SARS-CoV-2 are particularly problematic for people with chronic respiratory and other pre-existing health issues, like those caused by poor IAQ.
If we all do our part to enhance the quality of our indoor air, we can decrease the spread of disease and ensure a safer, healthier tomorrow.
For more information, please visit chemicalinsights.org.
All numbers presented in this diagram are approximate.
Technical Brief by Underwriters Laboratories - Coronavirus Aerosol
Global Initiative for Chronic Obstructive Lung Disease – World Lung Day 2019
American Lung Association – Volatile Organic Compounds
USEPA - Disinfectants for Use Against SARS-CoV-2 (COVID-19)
For more information on indoor air pollution visit www.chemicalinsights.org