§ 6819. Regulations making exceptions. The board shall promulgate regulations exempting from any labeling requirement of this article drugs, devices and cosmetics which are, in accordance with the practice of the trade, to be processed, labeled, or repacked in substantial quantities at establishments other than those where originally processed or packed, on condition that such drugs, devices and cosmetics are not adulterated or misbranded under the provisions of this article upon removal from such processing, labeling, or repacking establishment.