From Nedly's post:
Just a few things you need to know and rememeber for this weekend.

Weigh-in procedures
"You will pick up your weigh-in card from your district table and then proceed to the weigh-in area. You will go thru hair, nail and skin check. The ref will then sign your card and you procced to any scale. ""If you have special equipment or a skin release form you must have it at weigh-ins""

This would include the hair cover. Just show it to the officials.