All salvage operations shall be performed in buildings or structures with facilities, equipment and procedures which meet the following requirements:

1. (1) The exterior shall be so designed, fabricated, and finished as to minimize the easy entrance of insects, birds, rodents, and other vermin.
2. (2) All necessary ventilation openings shall be effectively screened against insects, rodents, and birds.
3. (3) All service connections through the exterior wall including water, gas, electrical, and refrigerator connections, shall be grommeted or sealed to prevent the entrance of insects, birds, and rodents.