Validation of calibration software ? as required by ISO 17025, for instance ? is a topic that folks don?t like to talk about. Almost always there is uncertainty concerning the following: Which software actually must be validated? If so, who should look after it? Which requirements should be satisfied by validation? How can you do it efficiently and how is it documented? The following blog post explains the background and gives a recommendation for implementation in five steps.
In a calibration laboratory, software can be used, among other things, from supporting the evaluation process, around fully automated calibration. Regardless of the amount of automation of the program, validation always identifies the entire processes into that your program is integrated. Behind validation, therefore, is the fundamental question of whether the process of calibration fulfills its purpose and whether it achieves all its intended goals, that is to say, does it provide the required functionality with sufficient accuracy?
If you need to do validation tests now, you should be aware of two basic principles of software testing:
Full testing is not possible.
Testing is always dependent on the environment.
The former states that the test of most possible inputs and configurations of a program cannot be performed due to the large number of possible combinations. According to the application, the user should always decide which functionality, which configurations and quality features must be prioritised and that are not relevant for him.
Which decision is made, often depends on the next point ? the operating environment of the software. Depending on the application, practically, there are always different requirements and priorities of software use. Additionally, there are customer-specific adjustments to the software, such as regarding the contents of the certificate. But also the individual conditions in the laboratory environment, with an array of instruments, generate variance. The wide variety of requirement perspectives and the sheer, endless complexity of the software configurations within the customer-specific application areas therefore ensure it is impossible for a manufacturer to check for all the needs of a particular customer.
Correspondingly, taking into account the above points, the validation falls onto an individual themself. In Failure to make this process as efficient as you possibly can, a procedure fitting the following five points is recommended:
The data for typical calibration configurations ought to be thought as ?test sets?.
At regular intervals, typically one per year, but at the very least after any software update, these test sets ought to be entered into the software.
The resulting certificates can be compared with those from the prior version.
Regarding a first validation, a cross-check, e.g. via MS Excel, may take place.
The validation evidence ought to be documented and archived.
WIKA offers a PDF documentation of the calculations carried out in the software.
Note
For Assault on our calibration software and calibration laboratories, visit the WIKA website.g