Regulation 3 Compliance with relevant requirements
Subject to paragraphs (2) and (3) below, any waters classified under these Regulations shall be treated in relation to any period of twelve months as complying with the requirements specified in the Schedule to these Regulations for waters of the relevant class for any parameter if in that period in relation to those waters—
in the case of the parameter for pH, non-ionised ammonia, total ammonium, total residual chlorine or total zinc, 95 per cent of the samples taken for that parameter in accordance with regulation 4 below comply with the requirements;
in the case of the parameter for temperature or dissolved oxygen, the percentage specified in that Schedule of samples taken for that parameter in accordance with regulation 4 below comply with the requirements.
When the frequency of sampling is lower than one sample per month for any parameter mentioned in sub-paragraph (1)(a) above in relation to any waters classified under these Regulations, 100 per cent of samples taken for that parameter in accordance with regulation 4 in relation to those waters must comply with the requirements for that parameter specified in the Schedule to these Regulations for waters of the relevant class.
Non-compliant samples shall be ignored for the purposes of paragraphs (1) and (2) above if they are the result of a flood or any other natural disaster.