Funny thing haha...well not really but kinda... my chem sub the other day told us a story about HF and said that once in New York since there isnt much space to do work and stuff in apartments people go to these warehouse places that are cleaned out and then rented out to people in small sections so you can build yourself a table or w/e and then leave, so this guy was took old bath tubs and used HF to clean them and then sold them as antiques, next to him was a lady that was painting on a huge canvas and one day after the man had left the lady couldnt find a ladder to get to the top of her canvas and so she went nearby and borrowed some buckets of the HF not knowing it was HF and used them to stand on.... as you can guess she fell in and began to melt away into a puddle of nothing.. just kidding, but yes she fell in and after about two weeks the HF reacted with the Ca in her bones and so she was eaten inside out with HF.... the guy went to jail for two years (manslaughter) for not labeling the chemicals and i think not having a license for the HF...
moral of the story.... Dont use HF.