Yes knee pads for sure especially for those that are learning, we weren't allowed to use safety clothing or accessories as we worked in the 1860's context. We had to work carefully and as safely as possible, but even then accidents can happen.
All the working historic mills contained many questionable safety areas, but we did try and work in safety as much as possible using training and other methods.
That is why as you travel around the country many of the historic sites have only static displays whereas UCV was a completely operational site from one end to the other with around 125 costumed interpreters.