Your ircd needs to support a few channel modes. Such as +O (opers only) or +A (Admin only).
Without these modes you would need to either
1> turn on restricted (/cs set #Channel restricted on), then add only your staff to the op list and finally set the modelock to +pnt
or
2> modelock the channel to +ipnt and add your staff to the op list and to get in the staff member will have to invite themselves with ChanServ.