This water is considered to comply with the quality limits set by the order mentioned in the first paragraph of article R. 1321-38 when the following rules are complied with:
1° The water samples are taken, before treatment, at regular intervals in the same place;
2° Parameter values are below the mandatory limit values for 95% of samples and comply with the guide values for 90% of samples;
3° For the other 5% or 10% of samples, as appropriate :
a) The values of the parameters do not differ by more than 50% from those set, with the exception of temperature, pH, dissolved oxygen and microbiological parameters;
b) There can be no danger to public health;
c) consecutive samples of water taken at a statistically appropriate frequency do not deviate from the relevant values.
Exceedances of the quality limits set by the order mentioned in the first paragraph of article R. 1321-38 are not taken into account when they are the result of floods, natural disasters or exceptional meteorological circumstances.