Validation of calibration software ? as required by ISO 17025, for example ? is a topic that people don?t like to talk about. Often there is uncertainty about the following: Which software actually should be validated? If that’s the case, who should take care of it? Which Dazzling should be satisfied by validation? How will you do it efficiently and how could it be documented? The following 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 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 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?
To be able to do validation tests now, you should be aware of two basic principles of software testing:
Full testing is not 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 number of possible combinations. With regards 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 manufactured, often depends on the next point ? the operating environment of the program. With respect to the application, practically, there are always different requirements and priorities of software use. There are also customer-specific adjustments to the software, such as concerning 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. To make this technique as efficient as you possibly can, a procedure fitting the following 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 least after any software update, these test sets should be entered into the software.
The resulting certificates can be weighed against 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 should 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.