Setting permissions for SH Clan Forums

Where to I go and how do I check the permissions set for the Clan forums? I have been advised that a non-clan member was able to access both the open thread forum and the Internal forum (clan members only). Since I have been dealing with RL for sometime now, I must have missed when our clan forum was changed from TSH to SH. Was there a reason for this? I was under the impression that unless a member is a clan member, they can't even see the forum.