a) la méthode applicable énoncée aux sous-sections 2540A à 2540E du document intitulé Standard Methods for the Examination of Water and Wastewater, 20 édition, 1998, publié conjointement par l’American Public Health Association, l’American Water Works Association et la Water Environment Federation, avec ses modifications successives;
(a) the applicable method described in subsections 2540A to 2540E of Standard Methods for the Examination of Water and Wastewater, 20th Edition, 1998, published jointly by the American Public Health Association, the American Water Works Association and the Water Environment Federation, as amended from time to time;