Validation of calibration software ? as required by ISO 17025, for instance ? is a topic that people don?t prefer to talk about. Often there is uncertainty about the following: Which software actually must be validated? If that’s the case, who should look after it? Which requirements must be satisfied by validation? How does one do it efficiently and how could it be documented? The following blog post explains the background and gives a recommendation for implementation in five steps.
In a calibration laboratory, software is used, among other things, from supporting the evaluation process, around fully automated calibration. Whatever the degree of automation of the software, validation always identifies the complete processes into which the program is integrated. Behind validation, therefore, is the fundamental question of whether the procedure for calibration fulfills its purpose and whether it achieves all its intended goals, in other words, does it provide the required functionality with sufficient accuracy?
If you want to do validation tests now, you should be aware of two basic principles of software testing:
Full testing isn’t possible.
Testing is always influenced by the environment.
The former states that the test of most possible inputs and configurations of a program cannot be performed as a result of large number of possible combinations. According to Withheld , the user must always decide which functionality, which configurations and quality features must be prioritised and that are not relevant for him.
Which decision is manufactured, often depends on the next point ? the operating environment of the program. According to the application, practically, there are always different requirements and priorities of software use. Additionally, there are customer-specific adjustments to the program, such as regarding the contents of the certificate. But additionally Important 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 make it impossible for a manufacturer to test for all the needs of a specific customer.
Correspondingly, considering the above points, the validation falls onto the user themself. To make this technique as efficient as possible, a procedure fitting the following five points is preferred:
The info for typical calibration configurations ought to be defined 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 in to the software.
Sizable resulting certificates could be compared with those from the previous version.
Regarding an initial validation, a cross-check, e.g. via MS Excel, can take place.
The validation evidence should be documented and archived.
WIKA offers a PDF documentation of the calculations completed in the software.
Note
For more info on our calibration software and calibration laboratories, visit the WIKA website.