During the processing of seafood, what specific, actionable protocol must be rigorously enforced to prevent the transfer of 'najis' contaminants, particularly from non-halal or impure sources, to otherwise permissible products?

The specific, actionable protocol that must be rigorously enforced to prevent the transfer of 'najis' contaminants, which are ritually impure substances under Islamic law such as pork, blood, or alcohol, from non-halal or impure sources to otherwise permissible seafood products, centers on a comprehensive system of absolute segregation and meticulous purification. This begins with the physical separation of all non-halal raw materials, processing areas, and finished products from halal seafood operations. Dedicated processing lines, storage facilities, and equipment must be exclusively used for halal seafood. For instance, knives, cutting boards, conveyor belts, and containers that have contacted 'najis' substances must never be used for permissible seafood products. If, under highly exceptional circumstances, shared equipment becomes unavoidable, it must undergo a rigorous purification process known as 'taharah' immediately after contact with 'najis' and before touching any halal product. This purification involves a specific method of washing, typically multiple times with water, and for severe 'najis' like swine or canine contaminants, one of these washes must incorporate a cleansing agent such as earth or a specific detergent equivalent to thoroughly remove the impurity. All personnel involved in handling halal seafood must be meticulously trained on these 'najis' principles and must maintain strict personal hygiene, ensuring their hands, clothing, and footwear are free from any 'najis' contamination before commencing work on halal lines. Furthermore, dedicated receiving areas and distinct transportation vehicles are essential to prevent cross-contamination from non-halal shipments upon arrival at the facility. This holistic approach ensures that throughout every stage, from raw material receipt to final packaging, the integrity and 'halal' status of the seafood are maintained, preventing any 'najis' transfer.