I'm with Terry556 here. A PUWER assessment is a detailed equipment assessment, going through the PUWER regs form Reg 4 to Reg24, can be done on a new machine or an existing.
I expect my assessment documentation is very like Terry's, much of it is a checklist to ensure nothing is missed, so start by looking at the location of the machine, is that suitable, then maintenance, are ergonomic problems avoided, training, dangerous parts, guards and other protection, noise, vibration, controls, isolation, lighting, labels, signs, PPE etc etc., you see all these items if you go through the PUWER ACoP.
The findings of the PUWER assessment can then aid a fuller Risk Assessment which will put additional consideration into the machine's operation, e.g. materials used, making different products, cleaning the machine, manual handling, housekeeping etc.
JohnW