Chain of custody form, Westchester County Labs

NYC 9/11 Public Portal Document

See LAB0060. 9.3.3.3 Record the date, analyst, preparation of the test culture, results of the testing, and final conclusions (i.e. the cleaner is inhibitory, but is rinsed off well enough by routine procedures). 9.3.3.4 If the test indicates that routine procedures are not adequate to eliminate the effects of the cleaner, procedures are to be bolstered to include more rinsing. 9.3.4 Verification of Colonies 9.3.4.1 Verification of colonies is required monthly. 9.3.4.2 Ten positive and ten negative colonies are selected from both total and fecal coliform plates. Colonies that are difficult to identify as having a sheen or blue color should be evaluated. 9.3.4.3 The colonies are verified using tube media as described within the total and fecal coliform SOPs. 9.3.4.4 Record the date, analyst, samples used to provide colonies, morphology of colonies selected, and results of LTB, BOB, and EC/mug testing. 9.3.4.5 If colonies are found to be responding differently than expected, they may be identified. Supervisors are to discuss the differentiation of colony morphology. 9.3.4.6 Sample counts are to be reported in the verified results fields. 9.3.4.7 At all times, pinpoint fecal colonies are to be verified. These colonies are not to be counted unless they have been verified. 9.3.5 Cultures of known organisms 9.3.5.1 Reference cultures 9.3.5.1.1 Reference cultures are to be purchased from ATCC certified stocks. Certificates are to be retained for each reference culture. 9.3.5.1.2 Reference cultures are to be reconstituted and grown to provide viable organisms. The resulting culture shall be referred to as a stock culture. 9.3.5.2 Stock cultures 9.3.5.2.1 Stock cultures are assumed to have the appropriate biochemical responses, since they are only obtained from certified stocks. 9.3.5.2.2 Stock cultures are to be kept in the refrigerator and may be used to grow working cultures until the culture begins to show signs of degradation, including media breakdown or dehydration, or inappropriate test results. 9.3.5.2.3 Stock cultures are not to be held for more than three months. 9.3.5.2.4 Stock cultures are not to be sub-cultured to create working cultures more than five times. 9.3.5.3 Working cultures 9.3.5.3.1 Working cultures are made from the stock cultures, and will be used to prepare daily QC checks. 9.3.5.3.2 Each working culture may be used for one week. 9.3.5.3.3 Working cultures are not to be used to re-supply the stock culture. 9.3.5.4 Daily cultures 9.3.5.4.1 Daily cultures are used to set up QC tests for many

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NYC-WTC_000072020