As part of ongoing efforts to further help reduce the spread of COVID-19, United Airlines today announced the implementation of a new protocol that maximizes airflow volume through HEPA (high-efficiency particulate air) filtration systems throughout the boarding and deplaning processes. United staff and pilots are working to prepare all mainline aircraft to implement the new procedure starting on July 27.
Onboard air-conditioning and pressurization systems replace the entire volume of cabin air every two to three minutes and, in combination with HEPA filters, remove 99.97 percent of airborne particles, (including bacteria and viruses) during the entire time they’re in operation, both on the ground and in the air.
That means the air inside a United mainline aircraft’s cabin while boarding or deplaning is considerably cleaner than what you’re likely breathing during visits to the grocery store, restaurants and even some hospitals.
“The quality of the air, combined with a strict mask policy and regularly disinfected surfaces, are the building blocks towards preventing the spread of COVID-19 on an airplane,” United Airlines CEO, Scott Kirby, said in a statement.
Onboard United’s commercial aircraft, fresh air is directed downward from the ceiling vents and exits the cabin through vents in the floor and sidewalls. It then passes through HEPA filters and is mixed half-and-half with fresh air from the outside before being recirculated, providing a constant flow of clean air into the cabin.
Boeing’s studies suggest that the incorporation of this frequent air exchange and top-to-bottom flow pattern works to minimize the front-to-back migration of contaminants or aerosolized particles from other passengers (e.g., through sneezing or coughing). United has also partnered with the Defense Advanced Research Projects Agency’s (DARPA) to research the efficacy of onboard airflow configurations in stopping the spread of airborne particles.
“HEPA filters are an effective way to ensure clean air on an aircraft,” said Dr. James Merlino of The Cleveland Clinic, which partnered to develop the United CleanPlus initiative. “United’s new strategy of running the air filtration and circulation systems at maximum volume well before passengers board and until they deplane, adds one more layer of protection. In addition to air filtration, we have worked with the airline to enact measures such as mandatory masking, health screenings, disinfection, and touchless systems, as we believe layering on precautions, more than any one strategy alone, helps create the safest environment possible.”
