S.L. 549.21 · Quality Required Of Surface Water (S.L. 549.21)
S.L. 549.21 Art. 3Values for sampling.
For the purpose of these regulations, surface water shall be divided according to limiting values into three categories, A1, A2 and A3, which correspond to the appropriate standard methods of treatment given in Annex I. These groups correspond to three different qualities of surface water, the respective physical, chemical and microbiological characteristics of which are set out in the table given in Annex II.