Worked in construction for many years prior to SSNHL, as a General Labourer, right up to Contracts Manager, and all points in between, suffice to say, I know my hard hats …. I am just saying, as a one off, a hard hat cradle could be adjusted to incorporate a BAHA, without compromising the overall integrity of the hat itself, and therefore not infringing on it’s protective element. Thinking about the actual problem, I would imagine the actual cradle could quite easily be adapted to suit the BAHA, perhaps by raising the cradle headband slightly, and anchoring the BAHA as low as practically possible, I have 3 close friends with BAHA’s, although you would never know they wore them, I can’t spot them, because of their hair, and I have looked for them on many occasions. But, you would need to speak to the ENT surgeon, to see what is possible, maybe take the hard hat in at the appointment, the surgeon might be able to site the BAHA, slightly lower than normal? BAHA’s are wonderful hearing instruments for conductive hearing loss, my 3 friends are in the severe or profound threshold unaided, but with the BAHA’s you would never know they had a hearing loss at all, they are excellent aids…. Good luck on whatever route you choose, cheers Kev