One of my colleagues from years ago did something similar
They picked up a sack of dye powder and put it on the laboratory bench a bit heavily, only to have a large blue cloud greet them when he opened the sack. The dye was rapidly dispersed by being sucked into the ventilation system which did a good job of spreading it around the building, meaning that pretty much everyone had blue eyes and teeth for a couple of days.
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tarka_dall Like normal dall, only a bit more spicy, Sat 2 Feb 2019, 9:04,
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