After scenario:

The operating program was modified to ensure correct sequencing of the sterilant dosing pump and feed valve. During cleaning of pipe lines the sterilant pump is 'cycled' on/off although the feed valve remains open. This is to assist in the distribution of sterilant around the CIP circuit rather than inject a single 'slug' into the CIP stream.

Case Study No.2 Shows poor pump and valve sequencing resulting in no sterilant (biocide) being added to the CIP circuit.

Before scenario:

The upper green line represents the sterilant dosing pump, the lower green line shows the operation of the sterilant return valve (pressure-relief valve. The red line is the operation of the actual sterilant feed valve, permitting sanitiser to be injected into the CIP stream. In this example, pump and feed valve were not synchronized resulting in no sanitiser actually being added to the circuit.