Two humans go to the infirmary with hands covered in blisters. At first, the medic thinks they got heat-burned. But the tests show the blisters are from frostbite. When asked, the humans shrug and went "We wanted to see who could hold ice in our hands the longest, and to make it more fun, we added salt to our hands, first. We were just goofing off." -- Anon Guest
The leading cause of dangerous injury to Humans was Humans "just goofing off" as they put it. It was so widely known that the EMT's had a special scramble alert for any security pickup that caught the phrase, "Hey, watch this!" There was a bigger one for, "Hold my beer." Humans are notorious that way.
Medik Rentsh sighed and said, "If I wasn't devoted to my work, I'd let you two suffer your consequences." Ze got out the dermal regeneration gear and assessed who had the most damage for small triage.
"The salt was a mistake," admitted Human Kin. "I remembered what salt does five seconds after the ice stuck to my hand."
"That's generally when the science kicks in," contributed Human Jae. "Five seconds after the derp moment."