I agree that NO HAIR should be below the helmet. I have hair down to my waist-it all goes on top of my head before the helmet goes on. I didn’t wear a sock while racing, but had a good way of securing it and it never came down.
Even 6 inches in a sit up-what happens if a seat strut breaks or because of accident head gets thrown too far back. I just wouldn’t take the chance even if a scenario is far fetched. Heck I put it up when playing on indoor karts where I am way above the axels.