Electrical interfaces are specified based on serial protocols, such as RS232 or RS485, or based on the Ethernet/TCP/IP protocol.
These interfaces allow a data transfer, or even a remote control of the integrity tester, by a PLC or MES software.
Data handling involved in integrating an integrity tester into a filtration process can generally be accomplished in one of
two ways: electronic data storage in a 21 CFR Part 11 environment or hard copy printouts where no data are stored. Hard copy is not covered under 21 CFR Part 11.9,10
In addition to deciding on the method of data storage, the integrity tester needs to be qualified before it can be used in
the production environment. Qualification is typically divided into three steps, namely Installation Qualification (IQ), Operational
Qualification (OQ) and a Performance Qualification (PQ). We cover this later.
When working with electronic data storage, many factors must be considered to properly integrate the integrity tester into
the IT process. Not only must the integrity tester fit into the 21 CFR Part 11 environment, but also all other equipment (PLCs, computers, SCADA systems) involved in the data transfer must fit.
Also, one must consider the method of data transfer. There are many standards in industry for equipment communication. Some
of the more common ones found on integrity testers are Ethernet and OPC servers for communication to computers and RS-232
and Profibus DP for communication to PLCs.
Pay attention to when and how often data are to be transferred from the integrity tester. Integrity testers usually have the
ability to transfer data automatically (as it is being created or time based) and manually. It is important that the data
be transferred in a timely fashion to a designated computer where the data can be properly archived and backed up. While
integrity testers may have the memory to store large amounts of data, they are not intended as the sole data storage location
for integrity test data (transient data).
In principle, two strategies for electronic data handling are common. First a strategy described as the "stand alone" setup
is based on the capability of the state-of-the-art devices to process and store data. The device is only connected from time
to time to the process network containing the archive servers or MES systems. This device needs to have the capability to
store data (integrity test parameters as well as test results) since GMP-relevant data are being stored. An audit trail, or
user access management, is required since all 21CFR Part 11 requirements have to be met in the device.
In the second setup, the devices are permanently connected to the process network. Due to this permanent connection, in most
cases all relevant GMP data are not stored on the device, but directly received from or sent to the MES or PLC system ("unique
source principle"). The supervising network can handle the start of integrity tests and running the complete test procedure.
Since GMP data are not stored on the integrity test device, it is only a part of a 21 CFR Part 11 system.