a) la méthode énoncée aux sous-sections 5210A et 5210B 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 method described in subsections 5210A and 5210B 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;