Horror Box,
Thankyou for the links. I have seen the Norwegian text before, but never translated it although was aware of the increased noise levels experienced by S92 Pilots.
Correct me if I am wrong though, that report doesn't look at noise levels experienced by S92 Pilots (or indeed their simulator) wearing helmets. I think what is needed here is a similar report being conducted with the pilots and the HATS dummy wearing helmets. I suspect that my hearing has been damaged whilst wearing a helmet, I would only wear one again (and gladly) if it is proven to be better than alternatives (or there is an increased risk of crashing!).