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 concerning the following: Which software actually must be validated? If so, who should look after it? Which requirements must be satisfied by validation? How would you take action 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 activities, from supporting the evaluation process, up to fully automated calibration. Whatever the amount of automation of the software, validation always identifies the complete processes into which the program is integrated. Behind validation, therefore, may be the fundamental question of if 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?
In order to do validation tests now, you ought to know 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. Based on 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 program. With respect to the application, practically, you can find always different requirements and priorities of software use. There are also Sturdy -specific adjustments to the program, 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 variety 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 specific customer.
Correspondingly, considering the aforementioned points, the validation falls onto an individual themself. To make this process as efficient as possible, a procedure fitting the next five points is recommended:
The data 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 ought to be entered in to the software.
The resulting certificates could be weighed against those from the previous version.
Regarding an initial 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, visit the WIKA website.