The defect of the product which it follows in the PL(Product Liability) enforcement or is forecast with the fact that in the PL due to a flaw the social loss of the enterprise will increase with application, will be the actual condition where the countermeasure against here upon is urgent. It changes from the next product production and there is to a countermeasure of percentage enterprise and it approaches the PL which leads the objection where is also the preservation with the place where it establishes the PL countermeasure of advance prevention dimension it presents a direction and the plan which are appropriate. The research which it sees the product liability with plant maintenance has a what kind of relationship, there probably is a maintenance what kind of the plan process of plant from the product liability to examine, will reach and the confrontation plan which leads researches it isn`t against.