Validation of calibration software ? as required by ISO 17025, for example ? is a topic that people don?t prefer to talk about. Almost always there is uncertainty about the following: Which software actually must be validated? If so, who should look after it? Which requirements must be satisfied by validation? How does one take action efficiently and how is it documented? The following post explains the background and provides a recommendation for implementation in five steps.
In a calibration laboratory, software is used, among other activities, 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 that your program is integrated. Behind validation, therefore, is the fundamental question of if 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?
In order 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. Based on Enormous , the user must always decide which functionality, which configurations and quality features should be prioritised and that are not relevant for him.
Which decision is manufactured, often depends on the second point ? the operating environment of the software. Depending on the application, practically, there are always different requirements and priorities of software use. There are also customer-specific adjustments to the software, such as regarding the contents of the certificate. But additionally the individual conditions in the laboratory environment, with a wide range of instruments, generate variance. World of requirement perspectives and the sheer, endless complexity of the program configurations within the customer-specific application areas therefore make it impossible for a manufacturer to test for all the needs of a particular customer.
Correspondingly, taking into account the aforementioned points, the validation falls onto the user themself. To make this process as efficient as possible, a procedure fitting the following five points is preferred:
The data for typical calibration configurations should 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 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 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, go to the WIKA website.