Co‑products and By‑products > Setting Up a Co/By-product Operation > Setting Up Item Status Codes for the Base Process
  
Setting Up Item Status Codes for the Base Process
Base process items are never stocked in inventory. As a result, although base processes are entered as regular items, they are not processed as inventory items. Use item status codes to prevent any inventory transactions related to base process items. Item status codes are created and maintained in Item Status Code Maintenance (1.1.5). Only two transactions should be allowed for the base item:
ADD-PS, which occurs when the item is added to a product structure.
ADD-WO, which occurs when the item is added to a work order.