Validation of calibration software ? as required by ISO 17025, for example ? is Courage that folks don?t prefer to talk about. Almost always there is uncertainty concerning the following: Which software actually should be validated? If that’s the case, who should look after it? Which requirements must be satisfied by validation? How would you do it efficiently and how is it documented? The following 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. Regardless of the degree of automation of the program, validation always refers to the entire processes into which the 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, in other words, does it supply the required functionality with sufficient accuracy?
In order to do validation tests now, you ought to know of two basics 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 because of the large numbers of possible combinations. Based on the application, the user should always decide which functionality, which configurations and quality features should be prioritised and that are not relevant for him.
Which decision is made, often depends on the second point ? the operating environment of the program. According to the application, practically, you can find 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 also the individual conditions in the laboratory environment, with an array of instruments, generate variance. The wide selection of requirement perspectives and the sheer, endless complexity of the program 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, considering the aforementioned points, the validation falls onto the user themself. In order to make this technique as efficient as you possibly can, a procedure fitting the next five points is recommended:
The info for typical calibration configurations should be thought as ?test sets?.
At regular intervals, typically once a year, but at the very least after any software update, these test sets should be entered into the software.
The resulting certificates could be compared with those from the previous version.
In the case of 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 completed in the software.
Note
For further information on our calibration software and calibration laboratories, go to the WIKA website.