NYC-WTC_000229818

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan December 7, 2001 Indoor Air Quality Assessment Page 3 P.S. 234 (Manhattan) ATC Project No. 15-19125-0279

Table 2 shows the ranges for the lAQ parameters measured on all four days.

TABLE 2 REAL-TIME ENVIRONMENTAL MEASUREMENTS (INDOOR RANGE'OUTDOOR MAXIMUM)

miete. -W I I'M5Y30i ®ec.:2. ? .t. 'L.. .x f

iatuna 65.2-72.1/55.6 65.0-73.2/ 67.1 69.2 - 77.4/ 69.4 67.0-72.8/59.4

n 47.9-55.6/88.1 51.1 - 64.7/76.4 42.8-58.3/38.7 37.5-54.2/ 47.0

m 380-500/395 394-480/430 385 -480/390 370-460/368

1-2/3 1-2/2 0-2/1 0-2/2

32 - 59/65 48-110/104 24-38/18 33 -65/ 57

TWCsBI 0.0-0.9*/0.0 0.0-8.6*/ 0.0 0.0-21.0*/0.0 .0.0-2.4*/0.0

* Strong paint odor

DISCUSSION

Measurements of temperature, relative humidity, CO2, CO and respirable particulates were generally within the guideline ranges (Table 1). The particulate (PM2.5) readings indoors reflected the conditions outdoors. Some respirable particulate readings were above the EPA standard of 65 ug/mY This standard is a 24-hour average and ATC collected only instantaneous real-time readings. Elevated TVOC readings resulted directly from painting activity in the building on the days the readings were made. The odor had dissipated considerably by the last day of measurements.

It must be noted that all of these measurements were made m an unoccupied building. Only ATC personnel and custodial staff were present. Levels would be expected to be different in a fully occupied building. Temperature, relative humidity, CO2 and respirable particulates may all be expected to increase to varying degrees when the school is occupied.

CONFIDENTIAL, CITY_2IMCl0 0_0 01897990 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008 NYC-WTC_000229820