419. Where the analysis result indicates a Legionella pneumophila concentration of 1,000,000 CFU/L or more, the owner of the water cooling tower facility must(1) implement measures that will eliminate any water dispersion by aerosol, such as stopping the ventilators;
(2) immediately apply the decontamination procedure;
(3) identify the causes of the concentration above 1,000,000 CFU/L with the member or members of a professional order who drew up the maintenance program;
(4) apply corrective measures;
(5) verify the effectiveness of the corrective measures; and
(6) take a new sample in accordance with the paragraph 3 of section 407 and send it to the accredited laboratory for a new analysis of the Legionella pneumophila concentration.