Distributors of medical devices intended for reuse must provide information or instructions for reprocessing their products to ensure a clean reprocessing result that is essential for patient safety. This also includes some single-use medical devices that are sold non-sterile but are intended to be used in a clean, disinfected and, if necessary, sterile condition.

As per DIN EN ISO 17664 at least one automated process must be described in these instructions, unless the medical device is not suitable for such a process. In this case a manual process must be described. These instructions must con­tain specifications for cleaning (with precleaning as applicable), disinfection and/or sterilization of the products. As per the specification in DIN EN ISO 17664 these instructions have to be validated, i.e. laboratory tests must be carried out to verify that the specifications in the instructions genuinely result in the product having a cleanliness condi­tion with which it can be safely re-used on patients.

The tests within the validation of the instructions is performed by applying a defined test contamination to the product (according to the intended use - typical: blood for cleaning, bacteria for disinfection), with areas of the product which are difficult to access being afforded particular attention, and subsequently cleaning and disinfecting the product follows exactly in accordance with the instructions. It is assumed that the specifications of the instructions are precise enough to minimize any influence of the person performing the test on the result.

The success of the cleaning step is tested by measuring the reduction of protein contamination on the product. The success of disinfection can be determined from the reduction of a test organism suitable for testing disinfection.