NYC-WTC_000195194

NYC 9/11 Public Portal Document

........................................... AFDUsed NumberafUnltswitharwithout Number ofUnits with w A}U>s for the First cleaning One &r Nlore Oiierloads witkOverM w Yes 18 38.9% No Illi 4 57,1%

AFO Used Number of Units with or without A hOs Number of Units with at Percentage of Units with Jor the Second Cleaning Least One Overload Overloads

w iiiBiii iiiiiiiiiiiiB 0.05 No 40,0%

Number of Urttfs With or without AFDs Number ofumtsw/at Pefceniage of Units mtk for the Third Cieaning Least One Overioad Ovarloac/s Yes 2 0 0.0% No 0 NZA

5.10 HVAC System

The HVAC system was cleaned in two of the commercial units. The system was cleaned by professionals using equipment and techniques common to the industry that included HEPA- filtered vacuums, air whips, air washing and soap and water washes. Wipe samples were I* collected prior to cleaning and after cleaning for comparison. The results indicate that overall there was a reduction of an order of magnitude for the compounds which were detected. In The Food Exchange, lead was reduced from 1,310 pg/m’ to 159 pg/m^ (average), MMVF was reduced from 11,732 S/cm^ to<57.3 S/cm^. In the Lemongrass Grill, there was a reduction in w lead concentrations from 10,700 pg/m’ to 95.95 pg/m’ (average). This indicates that standard HVAC cleaning methods and equipment reduced the concentrations of WTC-related contaminants by an order of magnitude.

W w

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CITY_21MC100_011105347

NYC-WTC_000195313