If electronic data files of test results are stored on the integrity tester, the 21 CFR Part 11 requirements have to be fulfilled as mentioned above. But because the software capabilities of such a system are
much less than that of a common PC, smart solutions have to be found. For instance, electronic data should be stored in separate
files. By adding a checksum to each file and naming it with a unique non-reproducible name, it will have the required 21 CFR Part 11 features. Then, the computer or data historian (audit trail) can link the data file to the proper filter and product
batch records. This is commonly described as traceability and the file content can be checked for integrity based on the specific
checksum. The data file includes all test parameters as well as the actual integrity test value with a definitive pass or
fail result. Typically, additional information is also included in the integrity test result file such as product, product
lot, filter part number, and filter lot or serial number.
A large majority of existing processes do not have electronic data transfer capability and are organized by a paper-based
documentation system. Most integrity testers on the market will have an onboard printer, or a serial port for an external
printer. A printout is the only record of the integrity test and it is essential to make a photocopy. Typically, one copy
is stored in a safe location while another is incorporated into the batch records for each process run.
Qualification of an integrity tester is an important part of the process integration. Suppliers of integrity testers support
customers with the device, and with qualification protocols that are optimized for an efficient and secure qualification process
based on the supplier's know-how. Qualification support is typically available from the supplier and ensures that the qualification
can be performed in a professional manner. The documentation used, whether the integrity test results are electronic records
or hardcopy printouts, is very similar. Additional protocols are used when data transfer is involved.
Installation qualification. A qualification generally starts with the IQ. The purpose of the IQ is to provide documented verification that the integrity
tester complies with approved design intentions and the manufacturer's recommendations or requirements. Verification that
the proper documentation has been supplied with the unit, a physical inspection of the equipment, and a facility requirements
check are common items included in the IQ.
Operational qualification. The purpose of an OQ is to provide documented verification that the equipment performs as intended. There are many items
verified during an OQ, with some of the more difficult tests confirming that the actual integrity test result is within specification.
Typically, for bubble point, diffusion (forward flow), and water intrusion, the integrity test result will be compared with
a measured reference. For example, when testing for diffusion, it is common for the integrity result to be verified using
a mass-flow meter. IQ and OQ can be performed by the manufacturer of the integrity tester, or by the end user. Similarly,
the IQ and OQ protocols will typically originate from the manufacturer, with the end user using them as is, or modifying them
to their validation standards.
Performance qualification. The last part of a validation is the PQ. The purpose of a PQ is to provide documented verification that the equipment can
perform effectively and reproducibly based on approved standard operating procedures (SOPs). Typically, actual process filters
in the production environment are used during this testing. The end user's SOPs, as well as personnel, are used to perform
the PQ. The integrity tester manufacturer may be consulted during the PQ, but typically will not perform the protocols.
The integration of filter integrity testers impacts the filtration process, as well as the IT environment. Available integrity
testers offer a wide variety of integration options to perform in a laboratory and also in the process environment. Because
the integration concept is based on a standard device, which only has to be configured in an appropriate way, qualifying the
device within the customer's validation process can be done by using the integrity tester manufacturer's documentation. This
possibility leads to dramatically reduced efforts in the qualification procedure and should therefore result in a preferred
choice of standard integrity testers to carry out a filter integrity test step in a filtration process.