6. Causes of problems and corrective actions

6.1 General rules

When a problem is detected, it is customary to apply the solution (table 5 ):

1. Precise location and identification of the problem by answering the questions: what, how, when, where (temporary, local).

2. On-site verification of parameters (avoid sending samples to the laboratory as much as possible).

3. Based on the results, compile a list of probable causes.

4. If necessary, conduct a thorough laboratory test to identify the cause(s).

5. Preparation of measures and implementation.

6. Validation of effectiveness....