Flushing a urinal may produce an “alarming upward flow” of inhalable coronavirus particles, increasing the need for a face mask when in a public restroom, according to a new study.

The study, from Yangzhou University in China, which was published in the Physics of Fluid journal on Monday, showed that when flushed, a urinal will allow coronavirus particles to “travel faster and fly father” than a traditional toilet flush.

"Urinal flushing indeed promotes the spread of bacteria and viruses," researcher Xiangdong Liu said in a press release (via USA Today). "Wearing a mask should be mandatory within public restrooms during the pandemic, and anti-diffusion improvements are urgently needed to prevent the spread of COVID-19."

For the study, researchers measured urinal flushing with computer models, which estimated that in just five seconds into a flush, virus particles could reach a height of more than 2 feet above the ground.

This not only suggests that these particles can present a health risk, as the coronavirus has been found to be present in urine and feces, but they may also be from the last person that used the urinal, USA Today reported. These contaminated aerosol particles could then enter the mouth and spread the coronavirus.

The urinal research follows another study from Yangzhou University that looked at toilet flushes and the transmission of the coronavirus. Using computer models, the same researchers found that thousands of particles come out of a toilet within 70 seconds of a flush, reaching higher than a foot above the toilet bowl in half that time.

"It is reasonable to assume that the high-speed airflow will expel aerosol particles from the bowl to regions high in the air above the toilet, allowing viruses to spread indoors, causing risks to human health," the researchers said about the toilet study.

The researchers from Yangzhou University also suggest that public bathroom transmission of the coronavirus has already occurred as they reportedly cited local news reports of a couple who contracted the virus at restroom located near a Beijing food market where they worked.

"What’s worse, two of COVID-19 reemerging confirmed cases in Beijing have been reported to be infected from a public toilet, which practically proves the danger from the public restroom," the researchers said (via USA Today).

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The FBI is investigating four Honolulu police officers who are accused of forcing a man to place his mouth on a urinal inside a public restroom, Feb.3, 2018. A representational image of a public urinal. Getty Images