Is your CO2 indoor air quality safe?

Is your CO2 indoor air quality safe?

Dr. Koz was interviewed by cleveland.com regarding CO2 monitors and sensors for indoor air quality testing. See article here.

CLEVELAND, Ohio — Carbon dioxide sensors can’t tell whether COVID-19 is present indoors, but they can show if a space needs fresh air and more circulation.

The coronavirus is primarily transmitted through respiratory droplets, produced from actions like breathing, speaking or coughing. But the disease can also be airborne, according to the U.S. Centers for Disease Control and Prevention.

The more people speak and exhale, the more carbon dioxide is produced. Poor ventilation or air handling means fresh air isn’t being circulated, to spread out all that exhalation.

Hence, the CO2 meter.

Sensors measure the parts per million of carbon dioxide in the air, so if 1,000 PPM is the reading, that means 1,000 particles out of one million are carbon dioxide. The lower the number, and the closer the it is to outside air, the better. The global average in the atmosphere for 2019 was 409.8 ppm, according to climate.gov.

One of the most popular sensors on the market is the Aranet4 Home, priced at $250 and currently out of stock on Amazon, though production is ramping up. North America Aranet sales manager Matt Drinker thinks with new coronavirus variants coming into the fold, carbon dioxide monitoring will be “widely adopted” as the pandemic continues.

“It is an industrial tool, but it doesn’t cost industrial prices, and it doesn’t need industrial technicians to operate it and to set it up,” Drinker said.

Search #COVIDCO2 on Twitter, and you’ll find people around the world using carbon dioxide monitors in university classrooms, restaurants and anywhere else they spend time indoors.

California has even passed a law mandating CO2 indoor air quality monitoring to reduce COVID-19 transmission and infection risk in classrooms.

Here’s how it works: The Aranet4 Home is small enough to hold in your hand and uses a non-dispersive infrared sensor. The sensor has a gas chamber with an infrared light source, where carbon dioxide absorbs the light. An optical filter filters the light, except for the wavelength the carbon dioxide molecules can absorb to produce accurate carbon dioxide levels.

With green, yellow and red light indicators, customers can detect whether a room’s carbon dioxide levels are too high. If it’s red, you need more fresh air. The sensor can also be calibrated with what the outdoor air is.

“The easiest way is you open a window, or you know to turn on the fan or the ventilator,” said Peter D’Carlo, North America vice president of Aranet’s parent company, SAF Tehnika.

In Cleveland, where high temperatures are hovering in the 20s, opening windows isn’t ideal. For cities bearing the cold, building owners could improve the HVAC system instead.

Related: During 1918 pandemic, people opened windows. Now, HVAC experts suggest adding filters, purifiers instead

Another way to bring levels down would be to reduce the number of people in the room, said Dr. Koz Galatsis, founder of Forensics Detectors. The fewer number of people, the less exhalation there is in the room. Forensics Detectors makes a monitor that is priced at $125 on its website and $119.00 at Walmart.

The carbon dioxide monitor from Forensics Detectors uses an NDIR sensor, and it can be rested on a table or mounted onto a wall. The monitor can measure 0-5000 ppm and has an accuracy of plus or minus 50 ppm.