Friday 13th risk model of clean-in-place (CIP) in a milk plant

Abstract

The food industries are generally the world's largest manufacturing sector, and importantly one of the most stable. Clean-In-Place (CIP) is globally used as a standard unit-operation in these industries in which cleaning is achieved solely by circulating detergent solutions and water rinses for mechanical effect over targeted surfaces. CIP failure can have enduring adverse effects on plant viability and the general public health. Friday 13th failure modelling is a means of quantitative assessing unexpected failure in unit-operations processing. In this paper a novel Friday 13th failure analysis of a simplified CIP cleaning of a typical milk process plant is presented for the first time. Failure is defined as less than a 98 % removal of deposit thickness of proteinaceous material from wet surfaces. Results show that failure occurs from random within-system changes not attributable to human error or plant item failure. This case study illustrates the potential application of extended and refined Friday 13th failure modelling technology to evaluate more complex CIP cleaning. Refined Friday 13th failure modelling could be used also to assess the success of potential intervention strategies to reduce operational risk in both design and operation of CIP systems.