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 concerning the following: Which software actually should be validated? If so, who should take care of it? Which requirements must be satisfied by validation? How can you do it efficiently and how could it be 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 things, from supporting the evaluation process, up to fully automated calibration. Regardless of the degree of automation of the software, 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 supply the required functionality with sufficient accuracy?
In order to do validation tests now, you should be aware of two basics of software testing:
Full testing is not possible.
Testing is always dependent on 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 which are not relevant for him.
Which decision is made, often depends on the next point ? the operating environment of the software. With Lying 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 the individual conditions in the laboratory environment, with an array of instruments, generate variance. Critical 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 check for all the needs of a specific customer.
Correspondingly, considering the aforementioned points, the validation falls onto an individual themself. In order to make this technique 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 can be compared with those from the previous version.
In the case of an initial validation, a cross-check, e.g. via MS Excel, may take place.
The validation evidence should be documented and archived.
WIKA provides 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.