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New research finds the cabin environment minimizes the spread of particles from coughing and breathing

What happens when someone coughs next to other passengers on an airplane? New Boeing research shows the cabin environment significantly reduces and removes those cough particles from the air.

In fact, Boeing researchers say the design of the cabin and the airflow system create the equivalent of more than 7 feet (2 meters) of physical distance between every passenger—even on a full flight. The findings, along with the use of face coverings, enhanced cleaning and other safeguards lower the risk of passengers contracting COVID-19 during air travel.

“We found people seated next to each other on an airplane are protected from aerosol cough particles in the same way as when standing more than 7 feet apart in a typical building environment.”

Dan Freeman
Chief Engineer, Boeing Confident Travel Initiative

"Boeing modeled a passenger's cough in different seated locations to determine the number of cough particles that entered the breathing space of the other passengers," said Dan Freeman, the chief engineer for Boeing's Confident Travel Initiative . "We found people seated next to each other on an airplane are protected from aerosol cough particles in the same way as when standing more than 7 feet apart in a typical building environment."

Using a method of mathematical modeling known as computational fluid dynamics (CFD), Boeing researchers tracked particle movement inside the cabin. They then developed a separate CFD model of an office environment to compare with the airplane results. Based on the airborne particle count, the study found passengers sitting next to one another on an airplane is the equivalent of people maintaining physical distance in an office or building.

"Our team approached this from an engineering perspective and conducted data-driven analysis, simulations, modelling and testing, which have revealed very promising findings," said Vishwa Uddanwadiker, CTI probabilistic analytics leader. "The CFD models are now being validated through live cough particle testing conducted onboard an airplane, both on the ground and in flight."

Boeing shared the findings during an International Air Transport Association (IATA) press conference October 8, 2020. Both Airbus and Embraer presented independent research studies that also reached similar conclusions.

The findings followed the release of new air travel numbers for 2020. Based on the best available data, IATA reported more than 1.2 billion passengers have flown on more than 16 million flights, but there are fewer than 50 cases of suspected passenger-to-passenger transmissions onboard airplanes.

New research shows the cabin design and airflow (in blue) significantly reduces and removes cough particles (in pink).

In addition to screening and preventative protocols at the airport, as well as actions that passengers themselves can take, researchers say there are several reasons the cabin reduces passenger exposure to particles:

  • High air exchange rate (cabin air is completely refreshed every 2-3 minutes; normal buildings have between 2-5 air exchanges per hour)
  • Airflow from ceiling to floor in a circular pattern
  • High efficiency particulate air (HEPA) filters that trap 99.9%+ of particulates
  • Airplane seat configurations act as barriers (forward facing, high-back seating)

The research effort is part of Boeing's Confident Travel Initiative, working with airlines, global regulators, industry stakeholders, and others throughout the air travel industry to enhance existing safeguards and develop new solutions to ensure the health and safety of the air travel experience.


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