Aerosols sprayed from flushing a public urinal can spread COVID-19, a new study found

A new Chinese study of the COVID-19 coronavirus has found that it can potentially be transmitted by the cloud of aerosol triggered when a public urinal is flushed.The study, published in the journal Physics of Fluids, says wearing a mask should be mandatory even in public washrooms.Earlier studies have shown that the COVID-19 virus can be transmitted by faeces and urine.Scientists from Yangzhou University in China simulated and tracked virus-laden particle movements when urinals are flushed. "We used a method of computational fluid dynamics to model the particle movement that occurs with the act of flushing," said the study's co-author Xiangdong Liu.According to the researchers, flushing a urinal involves an interaction between gas and liquid interfaces, resulting in a large spread of aerosol particles released from the urinal.The simulations performed by the scientists revealed that the trajectory of the tiny particles ejected by flushing a urinal "manifests an external spread type, with more than 57 per cent of the particles travelling away from the urinal."They said when men use urinals within a public restroom, these tiny particles can reach their thigh within 5.5 seconds when compared to the toilet flush, which takes 35 seconds to reach slightly higher.However, according to Liu, particles from urinals "show a more violent climbing tendency. The climbing speed is much faster than toilet flushing."Since urinals are used more frequently within densely populated areas, the researchers pointed out that particles will travel faster and farther, posing a serious public health challenge.The study underscored the importance of wearing a mask in public places, especially in restrooms."From our work, it can be inferred that urinal flushing indeed promotes the spread of bacteria and viruses," Liu said."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," he added.