Forwarding WTC air monitoring scope for final review, Aug 2002

NYC 9/11 Public Portal Document

Environmental Protection Agency Pt. 763, Subpt. E, App. A

TABLE 1—NUMBER OF 200 MESH EM GRID OPENINGS (0.0057 mm2) that NEED TO BE ANALYZED TO MAINTAIN SENSITIVITY OF 0.005 STRUCTURES/CC BASED ON VOLUME AND EFFECTIVE FILTER AREA

Effective Filler Area Effective FBer Area 385 so mm 855 80 mm EwnaaiiaaimFigEg 24 S60 24 1.2S0 600 23 1,300 23 700 19 1,400 21 800 17 1,600 19 900 15 1,800 17 1,000 14 2.000 15 1,100 12 2.200 14 I 1,200 11 2.400 13 I 1,300 10 2.600 12 Recommended 1,400 10 2,800 11 1 Volume 1,800 9 3,000 10 I Range 1,800 8 3,200 9 Recommended I 1,700 0 3,400 9 Volume ____ 1,800 8 3,600 8 Range 1,900 7 3,800 8 I 2,000 7 4,000 8 I 2,100 6 4.200 7 2,200 6 4.400 7 2,300 8 4.600 7 2,400 6 4.800 6 2,500 5 5,000 6 2,600 5 5,200 6 2,700 5 5,400 6 2,800 5 5,600 5 2,900 5 5,800 5 3,000 8 6.000 5 3,100 6.200 5 3,200 4 6.400 5 3,300 4 6.600 5 3,400 4 6.800 4 3.500 4 7.000 4 3.600 4 7.200 4 3,700 4 7.400 4 3.800 4 7.600

Nate minimum volumes required: 25mm :560lilei8 37mm :1250Rere

FUer dameier o( 25 mm - effective area of 38$ sq mm Finer dameler ot 37 mm - effective area ol 8S5 sq mm

k. At the conclusion of sampling, turn the closed and appropriately Identified using a cassette upward before stopping the flow to waterproof label. Protect cassettes in indi­ minimize possible particle loss. If the sam­ vidual clean resealed polyethylene bags. pling is resumed, restart the flow before re­ Bags are to be used for storing cassette caps orienting the cassette downward. Note the when they are removed for sampling pur­ condition of the filter at the conclusion of poses. Caps and plugs should only be re­ sampling. moved or replaced using clean hands or clean 1. Double check to see that all information disposable plastic gloves. has been recorded on the data collection m. Do not change containers if portions of forms and that the cassette is securely these filters are taken for other purposes.

685

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