After meeting with the inspector in person, he has informed me that Air tight cans are required by the local building department, making it in effect a local energy code, which as we all know supercedes the NEC. It only applies to this village and two other small ones in my county.
I have found a source for air tite cans and they are not much more than IC rated cans. If they are really that much better I will install them everywhere.
