I don't own any powder actuated tools myself and I usually use tapcons or some kind of anchor for something like that. But I can remember very specifically holding a board for an old boss of mine while he shot it on about 7 or 8 years ago. The way we were standing, the gun was right next to my ear and it really got me good. I was an idiot, and my boss was a jackass for allowing me to be an idiot, but that was one of the incidents that led to me getting serious about hearing protection while I still have a little left. By the way, I probably flinched enough that I wasn't a real reliable way of holding the board on the straight and level anyhow.