I will throw in my two cents. I have never used gloves or any sort of protection apart from eye protection, although now I am moved i am going to get some cheap nitrile gloves.
Also, Metol Developers in particular are known to cause dermatitis. For B/W, I presume if one used no protection, using a Phenidone / Sodium Ascorbate film developer, and a PQ developer might be the way to go for prints, although hydroquione can be carcinogenic as well. I use my fixer for film 1 + 14 for 15 minutes for film, one-shot, so any contact i have had with fixer is dilute. Thiosulphates are not too bad, but the other things in it might not be pleasent, unless one used straight hypo?
I have done RA4 developing in a cupboard under the stairs last year when i lived in my home town but the chemical fumes gave me so much of a headache so i gave it a pass. I now do it in a large open room with ventilation, in this new flat the same will apply. I find RA4 chemicals worse than E6 and C41 in general handling and how irritant they are to my skin.