B-1.1, r. 3 - Safety Code
417. Where the analysis result indicates a Legionella pneumophila concentration equal to or greater than 10,000 CFU/L but below 1,000,000 CFU/L, the owner of the water cooling tower facility must
(1) identify the causes of the increase in the Legionella pneumophila concentration;
(2) apply corrective measures; and
(3) verify the effectiveness of the corrective measures.