
Article 1 
This Directive lays down technical specifications for chemical analysis and monitoring of water status in accordance with Article 8(3) of Directive 2000/60/EC. It establishes minimum performance criteria for methods of analysis to be applied by Member States when monitoring water status, sediment and biota, as well as rules for demonstrating the quality of analytical results.
Article 2 
For the purpose of this Directive, the following definitions shall apply:

1.. ‘limit of detection’ means the output signal or concentration value above which it can be affirmed, with a stated level of confidence that a sample is different from a blank sample containing no determinand of interest;
2.. ‘limit of quantification’ means a stated multiple of the limit of detection at a concentration of the determinand that can reasonably be determined with an acceptable level of accuracy and precision. The limit of quantification can be calculated using an appropriate standard or sample, and may be obtained from the lowest calibration point on the calibration curve, excluding the blank;
3.. ‘uncertainty of measurement’ means a non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, based on the information used.
Article 3 
Member States shall ensure that all methods of analysis, including laboratory, field and on-line methods, used for the purposes of chemical monitoring programmes carried out under Directive 2000/60/EC are validated and documented in accordance with EN ISO/IEC-17025 standard or other equivalent standards accepted at international level.
Article 4 

1. Member States shall ensure that the minimum performance criteria for all methods of analysis applied are based on an uncertainty of measurement of 50 % or below (k = 2) estimated at the level of relevant environmental quality standards and a limit of quantification equal or below a value of 30 % of the relevant environmental quality standards.
2. In the absence of relevant environmental quality standard for a given parameter, or in the absence of method of analysis meeting the minimum performance criteria set out in paragraph 1, Member States shall ensure that monitoring is carried out using best available techniques not entailing excessive costs.
Article 5 

1. Where the amounts of physico-chemical or chemical measurands in a given sample are below the limit of quantification, the measurement results shall be set to half of the value of the limit of quantification concerned for the calculation of mean values.
2. Where a calculated mean value of the measurement results referred to paragraph 1 is below the limits of quantification, the value shall be referred to as ‘less than limit of quantification’.
3. Paragraph 1 shall not apply to measurands that are total sums of a given group of physico-chemical parameters or chemical measurands, including their relevant metabolites, degradation and reaction products. In those cases, results below the limit of quantification of the individual substances shall be set to zero.
Article 6 

1. 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.
2. Member States shall ensure that laboratories or parties contracted by laboratories demonstrate their competences in analysing relevant physico-chemical or chemical measurands by:
(a) participation in proficiency testing programmes covering the methods of analysis referred to in Article 3 of this Directive of measurands at levels of concentrations that are representative of chemical monitoring programmes carried out under Directive 2000/60/EC, and
(b) analysis of available reference materials that are representative of collected samples which contain appropriate levels of concentrations in relation to relevant environmental quality standards referred to in Article 4(1).
3. The proficiency testing programmes referred to in paragraph 2(a) shall be organised by accredited organisations or internationally or nationally recognised organisations which meet the requirements of ISO/IEC guide 43-1 or of other equivalent standards accepted at international level.The results of participation in those programmes shall be evaluated on the basis of the scoring systems set out in ISO/IEC guide 43-1 or in the ISO-13528 standard or in other equivalent standards accepted at international level.
Article 7 

1. Member States shall bring into force the laws, regulations and administrative provisions necessary to comply with this Directive at the latest two years after its entry into force. They shall forthwith communicate to the Commission the text of those provisions.When Member States adopt those provisions, they shall contain a reference to this Directive or be accompanied by such a reference on the occasion of their official publication. Member States shall determine how such reference is to be made.
2. Member States shall communicate to the Commission the text of the main provisions of national law which they adopt in the field covered by this Directive.
Article 8 
This Directive shall enter into force on the 20th day following its publication in the Official Journal of the European Union.
Article 9 
This Directive is addressed to the Member States.
Done at Brussels, 31 July 2009.
For the Commission
Stavros DIMAS
Member of the Commission