Traces of the preceding products should be sought in these samples.
(For example, the adhesive used in swabs has been found to interfere with the analysis of samples.)9.2.2 The location from which the sample is taken should take into consideration the composition of the equipment (e.g. Rinse samples may give sufficient evidence of adequate cleaning where accessibility of equipment parts can preclude direct surface sampling, and may be useful for checking for residues of cleaning agents, e.g. Note: This method relies on the manufacture of a placebo batch which is then checked for carry-over of the previous product. It is difficult to provide assurance that the contaminants will be dislodged from the equipment surface uniformly.
Additionally, if the particles of the contaminant or residue are large enough, they may not be uniformly dispersed in the placebo batch.9.4.2 Samples should be taken throughout the process of manufacture.
Identical cleaning procedures should then be used for these products.4.2.1 The relevant cleaning records (signed by the operator, checked by production and reviewed by quality assurance) and source data (original results) should be kept.
The results of the cleaning validation should be presented in cleaning validation reports stating the outcome and conclusion.6.1 Normally only procedures for the cleaning of surfaces of the equipment that come into contact with the product need to be validated.
This will depend on the products being produced, whether the cleaning occurs between batches of the same product (as in a large campaign) or whether the cleaning occurs between batches of different products.6.4 The design of equipment may influence the effectiveness of the cleaning process.
Consideration should therefore be given to the design of the equipment when preparing the cleaning validation protocol, e.g.
Equipment sterilization processes may not be adequate to achieve significant inactivation or removal of pyrogens.9.1.1 Equipment should normally be cleaned as soon as possible after use.
This may be especially important for operations with topical products, suspensions and bulk drug or where the drying of residues will directly affect the efficiency of a cleaning procedure.9.1.3 The practice of resampling should not be used before or during cleaning and operations and is acceptable only in rare cases.
An acceptable strategy is to first manufacture the more dilute form (not necessarily the lowest dose) and then the most concentrated form.