i have an old frigidaire free standing freezer which was made in 1991. i want to get rid of. but i cant because i need to get rid of the R-12 gas in the compressor.

does anyone know if this gas is harmful to people, is it toxic? or flammable?
i plan on getting rid of it near an open window. should i wear a towel over my mouth, and gloves when i cut the line?