Counting Covid in the air you breathe
Durban - Green Flag inspectors have tested the air in two open spaces in uMhlanga and found the levels of carbon dioxide ‒ which can carry Covid-19 from infected people exhaling and indicate airflow ‒ are fairly low.
Durban University Technology environmental science students who will become inspectors in the Green Flag initiative that certifies restaurants and other businesses as meeting standards to reduce the chances of spreading Covid-19, this week took the project outdoors.
Strolling the new uMhlanga Lagoon Nature Reserve Boardwalk, they measured the density of carbon dioxide and found it to be about 523 particles per million.
“These readings indicate a 99% reduction of risk,” said inspector Yagna Hariparsad.
“You never say there is no risk. There is always a risk.”
On the beach, the device recorded 515, helped by the sea breeze. A smoke tube showed where the air was moving.
The beach and the boardwalk were closed to the public during stricter stages of lockdown.
“Where fresh air is concerned, we need to elevate air quality to a level similar to that of the ocean and climate change,” said Green Flag scientist Robert Randolph, warning that Covid-19 might not be the last pandemic.
The journey by minibus taxi to the beach and the forest was an opportunity for another reading. Before boarding, the device revealed 521 particles per million outside. On boarding, with 50% occupancy and closing the windows, it took two minutes to reach 1100 and then after two minutes of the windows being opened again, the measure was down to 800.
“At 800 it’s definitely time to mask up and start producing more air flow,” said chief Green Flag inspector Keegan Seeran.
Readings of 400 to 500 are considered low, 600 is safe, 800 requires mask cover and at 1 500 the carbon dioxide content in the air reduces people’s focus by 20%.
Similar to Blue Flag status awarded to beaches, Green Flag Certification of public spaces offers reassurance that a venue provides a safe public space, with adequate ventilation.
To acquire Green Flag Certification, an inspector assesses the air quality of the venue using a set of scientific criteria. Should the establishment meet the criteria, it will be issued with Green Flag Certification. The certification will specify the number of people that can safely occupy the space, without compromising the safety of patrons, as well as indicate optimal airflow configurations necessary to prevent an accumulation of airborne viral particles.
For further information, visit www.greenflagassociation.co.za
The Independent on Saturday