NYC-WTC_000189316

NYC 9/11 Public Portal Document

Mr Bernard P Orlan March 22 2002 Indoor Air Quality Assessment Page 4 H S for Leadership & Public Service (M894) ATC Project No 15 19125 0290 recommended concentration for sensitive individuals such as asthmatic people and children of 40

* The measurements made during this assessment were instantaneous readings the NPAAQS is a 24 hour average

TVOC Concentration

The TVOCs concentrations were 0 ppm inside the building These concentrations were below the AIHA guideline for odor control of 1 ppm The outdoor TVOC concentration was also 0 ppm

OBSERVATIONS

During this assessment ATC noted the following • The interior of the building appeared clean and free of dust and debris • The building was occupied at the time of the assessment • No smoke odor was detected in the building

FINDINGS

Based on the real time measurements the following fmdmgs are presented

1 Concentrations of CO and TVOCs were below applicable standards and guidelines 2 Ninety six (96) indoor measurement for temperature were above and thirty one (31) measurements were within the range of 68 to 75°F (at 50 percent relative humidity) recommended by ASHRAE Standard 55 1992 during the heatmg season (wintertime conditions) 3 Ninety nine (99) of the indoor measurements for relative humidity were below and twenty nine (29) were within the ASHRAE recommended range of 30 to 60 percent for occupant comfort 4 One of the indoor measurements for CO2 was above the ASHRAE Standard 62 1999 recommended maximum concentration of <700 ppm above the background level The highest reading (1233 ppm) was measured in room 815 at 2 42 PM with 38 occupants Levels above the recommended maximum do not indicate a health risk Carbon dioxide measurements are used as an indicator of available outdoor air The pnmary source of CO2 indoors is occupant respiration 5 All of the indoor measurements for PM2 5 were below the NPAAQS of 65 pg/m^ 24 hour average concentration of particulate matter 2 5 micrometers or less in aerodynamic diameter One (1) of the one hundred thirty seven (137) instantaneous indoor readings was above the USEPA recommended concentration of 40 pg/m^ for sensitive individuals such as asthmatic people and children All of the outdoor measurements were above the NPAAQS of 65 pg/m^ 24 hour average concentration of particulate matter 2 5 micrometers or less in aerodynamic diameter and the USEPA recommended concentration for sensitive individuals such as asthmatic people and children of 40 pg/m^

CITY_21MC100_003085552

NYC-WTC_000189319