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Scientists at University College London studying how the virus spreads have developed a robot which tracks how droplets move through the air.
In a world first, it's being used in a London hospital to track how Covid spreads.
It is hoped the robot can be used in theatres and tubes to discover how Covid spreads.
Using a super slo mo camera scientists will be able to monitor what difference things like ventilation, air conditioning and masks have.
Dr Andrea Ducci tells ITV News: "We create some droplets. The droplets getting out of the mouth of our android and then we look at this plume with a laser we can illuminate the droplets and we have a high speed camera which eventually will capture the position and then we can capture the images."
With a mask on "you don't see much" but remove the mask and it is a different story.
With the mask off, images capture a plume of the smallest droplets - potentially the most dangerous because they travel further and are more likely to be inhaled by other people.
Knowing how the droplets move in different settings is vital.
"The real beauty of this system is its controllable its measurable and its portable and because you can move the camera anywhere in whichever room you're in you can also see where the particles are going and measure things like what impact ventilation or air conditioning has on the spread."
In a world first, the android has been taken to University College Hospital. In the future there's scope to be used in theatres and on public transport.
Professor Laurence Lovat says: "We can take these androids into places we want to assess and assess how the droplets move around in real locations. We can then build computer simulations to ensure they match the experimental reality and then we can rapidly scale those up to understand how mitigation like face masks or fans or ventilation can impact on the risks of Covid transmission."
Whether for example opening the windows at the end of the carriages makes a difference or personal fan infront of patients.