Chain of custody form, Westchester County Labs

NYC 9/11 Public Portal Document

9.3 Other Procedures 9.3.1 Air Monitoring 9.3.1.1 Air monitoring is to be conducted monthly. 9.3.1.2 Air monitoring plates (using HPC media) are to be exposed for at least 15 minutes on microbiological work spaces, and one hour in microbiological hoods, during regular work hours. 9.3.1.3 The results must indicate that <1 CFU/min has grown. If that limit has been violated, the effected area must be wiped down with alcohol. If, upon re-testing, the result does not meet the criteria, refrigerator drip-trays and air-conditioning filters are to be cleaned or replaced. 9.3.1.4 Microbiological work is to be performed in an area where activities will not promote contamination. These include the following. 9.3.1.4.1 in a separate laboratory room, 9.3.1.4.2 In a laminar flow hood, or 9.3.1.4.3 In a work area that is at least ten feet away from the chemical analyses work area within the same room. 9.3.1.5 If the microbiology section is not isolated from other work by the preceding criteria, air monitoring must be performed during regular microbiological activities including the following. 9.3.1.5.1 The preparation and dispensing of media 9.3.1.5.2 The inoculation of tubes 9.3.1.5.3 During membrane filtrations and transfers. 9.3.1.6 Record the date, analyst, procedure being performed, and results. 9.3.1.7 If the results of the air monitoring testing indicate that the acceptance criteria has been violated, the specific work being performed is to be commented in the dataset. 9.3.2 Bacteriological Glassware Check 9.3.2.1 Bacteriological glassware is to be cleaned with soap. Alternately, glassware can be washed with citric acid. The following procedures are used to ensure that either soap or acid is rinsed from the glassware during normal rinsing procedures. 9.3.2.2 One item from each batch is to be checked for detergent residue with bromthymol blue using the following procedure. See EPA600/8-78-017, p. 199. 9.3.2.2.1 Add 4 drops of 0.04% bromthymol blue solution to 4ml of final rinse water. 9.3.2.2.2 0.04% bromthymol blue solution is prepared by adding 16ml of 0.01 N NaOH to 0.1g of bromthymol blue, followed by diluting to 250ml with distilled water. 9.3.22.3 A neutral reaction is indicated by a green color. An acid reaction is indicated by a yellow color. A basic reaction is indicated by a blue color. 9.3.2.3 Record the date, analyst, batch identification, and color results. 9.3.2.4 If the results indicate that soap is still present, the glassware is to be rinsed again and re-tested before use. If the test fails frequently, rinsing procedures are to be made more rigorous. 9.3.3 Soap Inhibitory Test 9.3.3.1 The soap used to wash bacteriological glassware is to be tested for inhibitory (or promoting) effects annually. 9.3.3.2 The test is also to be performed prior to the use of a new brand of cleaner.

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NYC-WTC_000071993