Annex III to Directive 98/83/EC is amended as follows:

1. (1)

   the introductory paragraph is replaced by the following:

   Member States shall ensure that the methods of analysis used for the purposes of monitoring and demonstrating compliance with this Directive are validated and documented in accordance with EN ISO/IEC 17025 or other equivalent standards accepted at international level. Member States shall ensure that laboratories or parties contracted by laboratories apply quality management system practices in accordance with EN ISO/IEC 17025 or other equivalent standards accepted at international level.

   In the absence of an analytical method meeting the minimum performance criteria set out in Part B, Member States shall ensure that monitoring is carried out using best available techniques not entailing excessive costs.

2. (2)

   point 1 is amended as follows:

   1. (a)

      the heading of point 1 is replaced by the following:

      PART AMicrobiological parameters for which methods of analysis are specified

   2. (b)

      the third to the ninth paragraphs, including Note 1, are replaced by the following:

      The methods for microbiological parameters are:

      1. (a)

         Escherichia coli (E. coli) and coliform bacteria (EN ISO 9308-1 or EN ISO 9308-2)

      2. (b)

         Enterococci (EN ISO 7899-2)

      3. (c)

         Pseudomonas aeruginosa (EN ISO 16266)

      4. (d)

         enumeration of culturable microorganisms — colony count 22 °C (EN ISO 6222)

      5. (e)

         enumeration of culturable microorganisms — colony count 36 °C (EN ISO 6222)

      6. (f)

         Clostridium perfringens including spores (EN ISO 14189)

3. (3)

   point 2 is amended as follows:

   1. (a)

      the heading of point 2 is replaced by the following:

      PART BChemical and indicator parameters for which performance characteristics are specified

   2. (b)

      point 2.1 is replaced by the following:

      1.Chemical and indicator parameters

      For the parameters set out in Table 1, the specified performance characteristics are that the method of analysis used must, as a minimum, be capable of measuring concentrations equal to the parametric value with a limit of quantification, as defined in Article 2(2) of Commission Directive 2009/90/EC17, of 30 % or less of the relevant parametric value and an uncertainty of measurement as specified in Table 1. The result shall be expressed using at least the same number of significant figures as for the parametric value considered in Parts B and C of Annex I.

      Until 31 December 2019 Member States may allow for the use of “trueness”, “precision” and “limit of detection” as specified in Table 2, as an alternative set of performance characteristics to “limit of quantification” and “uncertainty of measurement” as specified respectively in the first paragraph and Table 1.

      The uncertainty of measurement laid down in Table 1 shall not be used as an additional tolerance to the parametric values set out in Annex I.

      Table 1Minimum performance characteristic “Uncertainty of measurement”

      Parameters	Uncertainty of measurement(See Note 1)% of the parametric value (except for pH)	Notes
      Aluminium	25
      Ammonium	40
      Antimony	40
      Arsenic	30
      Benzo(a)pyrene	50	See Note 5
      Benzene	40
      Boron	25
      Bromate	40
      Cadmium	25
      Chloride	15
      Chromium	30
      Conductivity	20
      Copper	25
      Cyanide	30	See Note 6
      1,2-dichloroethane	40
      Fluoride	20
      Hydrogen ion concentration pH (expressed in pH units)	0,2	See Note 7
      Iron	30
      Lead	25
      Manganese	30
      Mercury	30
      Nickel	25
      Nitrate	15
      Nitrite	20
      Oxidisability	50	See Note 8
      Pesticides	30	See Note 9
      Polycyclic aromatic hydrocarbons	50	See Note 10
      Selenium	40
      Sodium	15
      Sulphate	15
      Tetrachloroethene	30	See Note 11
      Trichloroethene	40	See Note 11
      Trihalomethanes — total	40	See Note 10
      Total organic carbon (TOC)	30	See Note 12
      Turbidity	30	See Note 13
      Acrylamide, epichlorohydrin and vinyl chloride to be controlled by product specification.

      Table 2Minimum performance characteristics “Trueness”, “precision” and “limit of detection” — may be used until 31 December 2019

      Parameters	Trueness(See Note 2)% of the parametric value (except for pH)	Precision(See Note 3)% of the parametric value (except for pH)	Limit of detection(See Note 4)% of the parametric value (except for pH)	Notes
      Aluminium	10	10	10
      Ammonium	10	10	10
      Antimony	25	25	25
      Arsenic	10	10	10
      Benzo(a)pyrene	25	25	25
      Benzene	25	25	25
      Boron	10	10	10
      Bromate	25	25	25
      Cadmium	10	10	10
      Chloride	10	10	10
      Chromium	10	10	10
      Conductivity	10	10	10
      Copper	10	10	10
      Cyanide	10	10	10	See Note 6
      1,2-dichloroethane	25	25	10
      Fluoride	10	10	10
      Hydrogen ion concentration pH (expressed in pH units)	0,2	0,2		See Note 7
      Iron	10	10	10
      Lead	10	10	10
      Manganese	10	10	10
      Mercury	20	10	20
      Nickel	10	10	10
      Nitrate	10	10	10
      Nitrite	10	10	10
      Oxidisability	25	25	10	See Note 8
      Pesticides	25	25	25	See Note 9
      Polycyclic aromatic hydrocarbons	25	25	25	See Note 10
      Selenium	10	10	10
      Sodium	10	10	10
      Sulphate	10	10	10
      Tetrachloroethene	25	25	10	See Note 11
      Trichloroethene	25	25	10	See Note 11
      Trihalomethanes — total	25	25	10	See Note 10
      Turbidity	25	25	25
      Acrylamide, epichlorohydrin and vinyl chloride to be controlled by product specification.

   3. (c)

      point 2.2 is replaced by the following:

      2.Notes to Tables 1 and 2

      Note 1	Uncertainty of measurement is a non-negative parameter characterising the dispersion of the quantity values being attributed to a measurand, based on the information used. The performance criterion for measurement uncertainty (k = 2) is the percentage of the parametric value stated in the table or better. Measurement uncertainty shall be estimated at the level of the parametric value, unless otherwise specified.
      Note 2	Trueness is a measure of systematic error, i.e. the difference between the mean value of the large number of repeated measurements and the true value. Further specifications are those set out in ISO 5725.
      Note 3	Precision is a measure of random error and is usually expressed as the standard deviation (within and between batches) of the spread of results from the mean. Acceptable precision is twice the relative standard deviation. This term is further specified in ISO 5725.
      Note 4	Limit of detection is either: three times the standard deviation within a batch of a natural sample containing a low concentration of the parameter, or five times the standard deviation of a blank sample (within a batch).
      Note 5	If the value of uncertainty of measurement cannot be met, the best available technique should be selected (up to 60 %).
      Note 6	The method determines total cyanide in all forms.
      Note 7	Values for trueness, precision and uncertainty of measurement are expressed in pH units.
      Note 8	Reference method: EN ISO 8467
      Note 9	The performance characteristics for individual pesticides are given as an indication. Values for the uncertainty of measurement as low as 30 % can be achieved for several pesticides, higher values up to 80 % may be allowed for a number of pesticides.
      Note 10	The performance characteristics apply to individual substances, specified at 25 % of the parametric value in Part B of Annex I.
      Note 11	The performance characteristics apply to individual substances, specified at 50 % of the parametric value in Part B of Annex I.
      Note 12	The uncertainty of measurement should be estimated at the level of 3 mg/l of the total organic carbon (TOC). CEN 1484 Guidelines for the determination of TOC and dissolved organic carbon (DOC) shall be used.
      Note 13	The uncertainty of measurement should be estimated at the level of 1,0 NTU (nephelometric turbidity units) in accordance with EN ISO 7027.

4. (4)

   point 3 is deleted.