NYC 9/11 Public Portal Document
Post P‘ deeming Semtples - Two air samples were collected. The results for both samples
were below the primary clearance criterion of 10 SZL.
Mattress Store - This is a 968 sq. ft. open space facing the World Trade Center site. All front
windows were blown in. Significant amounts of dust were present on all horizontal surfaces.
Floor areas were covered with wall-to-wall carpeting. Approximately 25 display mattresses and
box springs were present. Ceiling tiles, mattresses, office equipment and flexible ventilation ducts
were removed and disposed of prior to cleaning. The space above the suspended ceiling exhibited
the same characteristics as in the Chiropractor’s Office.
deeming Method - This unit was the subject of separate tests to evaluate five different cleaning
techniques as described below;
Test 4A: Industrial HEPA-filtered vacuums and AFD
Test 4B: Wet wipe all walls
Test 4C: Hot water carpet shampoo
Test 4D: A/C duct cleaning
Test 4E: Cleaning of vinyl floor tile and wet wipe of window ledge using water only
deeming Results - This unit met the clearance criteria listed in Table 1.0 for each compound after
the Test 4E cleaning event except for one lead wipe which was collected from a window ledge.
Supplemental Seimpling Activities - Prior to initiating pre-cleaning sampling activities as
described below, EPA collected a bulk composite sample from the Mattress Store. The analytical
data obtained from the bulk composite was utilized in identifying COPC concentrations present in
settled dust, determining the applicability of regulatory standards, and identifying potential health
and safety concerns. The Mattress Store was selected, based upon visual observation, as being
representative of a “worst case scenario” in the study building.
Asbestos
Before deeming Seanples - Four air, seven micro vacuum, and three wipe samples were
collected for asbestos. The air samples were analyzed for PCM and PCMe. The PCM
results indicate that two of the samples were above and two of the samples were below
the secondary numeric criterion of 0.01 free. The PCMe results indicate that two of the
samples could not be analyzed due to overloading of particulate material. The remaining
two samples were below the detection limit and below the primary clearance criterion of
0.0009 S/cc. All seven of the micro vacuum samples and all three of the wipe samples
detected chrysotile.
Post Cleaning Samples (Test 4A) - Three air samples, seven micro vacuum samples
and four wipe samples were collected for asbestos. The air samples were analyzed for
PCM, TEM AHERA, and PCMe. The PCM results indicate that all three samples were
below the secondary numeric criterion of 0.01 free. The TEM AHERA results indicate
that two of the samples could not be analyzed due to overloading of particulate material.
The remaining sample was below the secondary numeric criterion of0.0022 S/cc. The
PCMe results indicate that two of the samples could not be analyzed due to overloading of
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