IMPROVING ventilation and limiting carbon dioxide emissions in indoor settings can help reduce the transmission of viruses, including Covid-19 virus.
This was the focus of the discussion of the Zoom meeting on Monday, September 20, 2021, organized by the IATF-Visayas and the Office of the Presidential Assistant for the Visayas (OPAV).
IATF-Visayas and OPAV have organized several meetings with various concerned sectors to identify measures that could help in the safe reopening of the Cebu economy.
During the Monday meeting, Dr. Antonio "Tony" Dans and Dr. Leonila Dans of the Healthcare Professionals Alliance Against Covid-19 (HPAAC) spoke on how to mitigate the transmission of the Covid-19 virus by reducing carbon dioxide emissions in an indoor setting through proper ventilation.
A CO2 emission of 400 parts per million (ppm) is considered safe, while a CO2 emission of 400 ppm to 500 ppm is acceptable. An 800 CO2 emission is risky and a 4,400 ppm is dangerous, Dr. Antonio Dans explained.
He noted that the efficacy of masks diminishes in an indoor setting, so there’s a need to improve ventilation and reduce CO2 emissions.
"The higher the CO2 level, the more of the air your breathing comes from other people," he pointed out. A person inhales and exhales 10 liters of air per minute.
On the other hand, Dr. Leonila Dans stressed the importance of having good ventilation in combination with wearing of face masks, physical distancing and limited time of exposure as a way to reduce transmission.
They explained that indoor ventilation can be improved by exchanging indoor air with outdoor air, which is the inexpensive way of reducing CO2. This can be done by keeping the windows open and through the use of exhaust fans.
For windowless areas, high efficiency particulate air (hepa) filter devices can be used. Hepa filters trap the droplets of respiratory infections (or other particles) that viruses have attached to and prevent them from remaining in an indoor environment.
Both doctors also noted that measuring air quality could be helpful in coming up with measures to reduce transmission.
"We should start monitoring air quality if you want to make sure that schools and workplaces are safe," Dr. Leonila said.
On Monday, Malacañang announced that President Rodrigo Duterte has approved the holding of pilot face-to-face classes in areas with minimal risk for Covid-19.
The pilot face-to-face classes, which will be half-days every other week, will be allowed in 100 public schools and 20 private schools.
Implementing proper ventilation would help the pilot schools reduce transmission risks.
Dr. Tony explained that there are several CO2 monitoring devices available in the market which can be used to determine the CO2 emission levels in an indoor setting. However, there are devices that are more accurate than others available in the market.
An article on the research from the Cooperative Institute for Research in Environmental Sciences (CIRES) and the University of Colorado Boulder noted the "tracking CO2 levels indoors is an inexpensive and powerful way to monitor the risk of people getting Covid-19." The article was published on Science Daily on April 7, 2021.
The research was based on the fact that CO2 can serve as a "proxy" for a number of viruses in the air.
Edmun Liu of Project Balik Buhay suggested that guidelines focus only on air quality standards requirement and allow businesses to determine how to achieve the set standard.
Meanwhile, Department of Health Region 7 chief pathologist Dr. Mary Jean Loreche suggested that the approach to the safe reopening of the economy should also include small businesses such as the carenderias, barber shops and beauty salons.
The meeting participants include IATF-Visayas chief implementer retired M/Gen. Melquiades Feliciano, infectious disease specialist Brian Lim, Dr. Helen Madamba of Vicente Sotto Memorial Medical Center and other Cebu-based physicians, among others. (PR)