NYC-WTC_000232959

NYC 9/11 Public Portal Document

Table 11 Summary of Minerals in Indoor and Outdoor Air From Lower Manhattan and Comparison Buildings Above 59th Street *** Air Samples from Lower Manhattan Air Samples From Comparison Buildings Number Number of Quartz Calcite Portlandite Gypsum Mica Halite of Quartz Calcite Portlandite Gypsum Mica Halite Samples Samples PM 100 Number (Frequency 14 (14%/ 9 (9%) 8(8%) 24 (24%) 2 (2%) 4(4%) Nl/ ND ND 1 (14%) ND ND detected %) 101 7

Air Concentration 3-13? 3-141 16-951 3-141 9-131 4-141 31 (ttg/m’) PM 10 Number (Frequency 11 (10%) 10 (10%) 10(10%) 33(31%) 1 (1%) 5 (5%) ND ND ND 3 (30%) ND ND detected %) 105 10

Air Concentration 3-121' 3-51 14-251 3-141 81 4-51 31 (itg/m’) PM 4 Number (Frequency 13 (11%) 13(11%) 12(11%) 40 (35%) 4 (4%) 3 (3%) 11 ND ND ND 3 (27%) ND ND detected %) 114

Air Concentration 4-191 4-101 21-841 4-151 14-431 7-191 51 (ttg/mO PM 2.5 Number (Frequency 1 (3%) ND ND 1 (3%) ND ND ND ND ND 1 (17%) ND ND detected %) 34 6

Air Concentration 31 31 31 (itg/rn^) Range of Detection Limits (tig/m’) PM 100 I 2-51 2-51 12-261 2-51 7-151 4-81 2-51 2-51 12-261 2-51 7-151 4-81 PM 10 2-51 2-51 12-261 2-51 7-151 4-81 2-51 12-261 7-151 4-81 PM 4 4-61 4-61 20-301 4-61 11-171 6-91 4-61 4-61 20-301 4-61 11-171 6-91 PM25 2-41 2-41 13-201 2-41 7-111 4-61 2-41 2-41 13-201 2-41 7-111 4-61 O H a. Where two samples were co-located—the greatest value of the two was included in this summary. Each location is only represented once in this table. b. Concentrations shown are estimated values, indicated by “1.” c. Air samples from all locations, indoor and outdoor, are pooled in this table due to uncertainties in the data. S d. Cristobalite, a different crystalline form of silica, was found in one Lower Manhattan air sample at 15 micrograms per cubic meter of air fttg/iii') 1 in the PM 100 fraction. O e. .1 = estimated. O f. ND = not detected. O I o

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