Someone should point out that forging is not necessarily deafening. The best way to work iron or steel with a hammer is when it's soft, so when it's hot. In such a state, it doesn't ring. The anvil itself can have a ring to it, which could be damped in the period with mounting it ( though modern tricks often involve wrapping with rubber) or wrapping it with chain. But it's more of a problem with modern anvils: an iron anvil or steel-faced iron anvil has a lot more internal friction and is not as bright.
But crappercreeper is not wrong. Just because making a forge weld is not that loud doesn't mean a blacksmith would not be working in a loud shop and going deaf from it. Several smiths in a small space can still make a racket, and when blacksmiths often are found in larger metalworking and machine shops in the 19th c., there are plenty of other things to make them deaf.