NYC 9/11 Public Portal Document
300 pg/m^.
Fifth Floor Hallway - The fifth floor hallway is an area with plywood floors and walls made of
sheet rock covered with wallpaper glue. The ceiling is also made of sheet rock, and is painted.
Cleaning Method - This area was cleaned twice using Test 4A and Test 4B. Test 4A used an
industrial HEPA-filtered vacuum and an AFD, while Test 4B consisted of a soap and water wet
wipe of only the ceiling.
Cleaning Results - This unit met the clearance criteria listed in Table 1.0 for each compound after
being cleaned twice.
Asbestos
Before Cleaning Samples - There were no samples collected before cleaning.
Post P‘ Cleaning Samples - Two air samples were collected. The air samples were
analyzed using PCM. The PCM results were below the secondary numeric criterion of
0.01 f7cc. The samples could not be analyzed for PCMe, due to overloading of particulate
matter on the filters.
Post 2^ Cleaning Samples - Two air samples were collected. The air samples were
analyzed using TEM AHERA, and PCMe. The samples could not be analyzed for PCM,
due to overloading of particulate matter on the filters. The TEM AHERA results were
below the secondary numeric criterion of 0.022 S/cc, with the samples being below the
detection limit. Similarly, the PCMe results were below the primary clearance criterion of
0.0009 S/cc with the samples likewise below the detection limit.
Dioxin
Before Cleaning Samples - There were no samples collected before cleaning.
Post Cleaning Samples - There were no post-first cleaning samples collected.
Post 2'“' Cleaning Samples - There were no post-second cleaning samples collected.
Gypsum
Before Cleaning Samples - There were no samples collected before cleaning.
Post P‘ Cleaning Samples - One air sample was collected after the first cleaning. Gypsum
was not detected. Since gypsum was below the detection for the sample collected, no
additional gypsum samples were collected.
Lead
Before Cleaning Samples - There were no samples collected before cleaning.
Post f Cleaning Samples - One air sample was collected after the first cleaning. The air
sample was below the primary clearance criterion of 1.0 pg/m’. Since the primary
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