• A new report says airlines' pandemic boarding processes may actually have increased the risk of Covid-19 exposure.
  • Back-to-front boarding is "substantially worse" than random boarding, the scientists found.
  • The researchers also said banning the use of overhead luggage bins significantly reduces exposure.
  • For more stories visit Business Insider.

Airlines including Delta, JetBlue, Southwest, and United temporarily switched to back-to-front plane boarding during the pandemic to cut down on unnecessary close contact between passengers. But a new study says this method - filling aisles one-by-one from the back - could actually double your chance of being exposed to Covid-19 compared to random boarding.

Using middle seats and letting passengers stow luggage in overhead bins also increases the risks of Covid-19 exposure, according to the study published in the Royal Society Open Science journal Wednesday.

Scientists from US colleges including West Florida and Arizona State simulated various boarding processes and looked at how often people came into close contact with other passengers. Bloomberg first reported on the study.

The scientists said that airlines introduced back-to-front boarding so that people could avoid passing by people sat in other rows when they took their seats.

But the research found that back-to-front boarding increased the amount of contact between pairs of seated passengers, and between pairs of passengers in the aisle.

The scientists said airlines could have had a roughly 50% lower risk of infection if they stuck to their pre-Covid-19 boarding process, where they typically let the business class boards first, followed by the economy class, with passengers sorted into various zones.

"Our results suggest that the new boarding procedures increase the risk of exposure to Covid-19 compared with prior ones and are substantially worse than a random boarding process," the scientists wrote.

JetBlue, Southwest, and United have all dropped the policy, and Delta is reverting to its pre-pandemic boarding from May 1.

The researchers also said banning the use of overhead bins to stow luggage "significantly" reduces exposure. This is because passengers often cluster in the aisles while they wait for other people to stow their luggage.

The report added that keeping middle seats empty reduced the risk of exposure, too, echoing a recent CDC report that said that middle-seat blocking may reduce Covid-19 spread on airplanes by up to 57%.

Delta is the only major US airline still blocking middle seats, but has said it would stop doing so May 1. The Trade organisation Airlines for America indicated to Insider's Thomas Pallini that it wouldn't recommend any changes following the CDC's report.

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