re: #732 Teukka

Rockwool and glass fiber wool aren’t that harmful provided you use them properly and in a way which contains the fibers if there is a hole in the wall etc. Post-construction cleaning is also key.

As to plaster, NOPE!, I would go with 2 layers of drywall, one of the fire rated variety. On each side of the rockwool.

Drywall here is extremely uncommon. The vast majority of residential apartment buildings here are either masonry or interlocking concrete panels. Family homes are usually masonry.