NYC-WTC_000196414

NYC 9/11 Public Portal Document P.C7 Pug 2 2QC0 00 atr-eo-duUl FKi 12:45 NIOSH/R-II FAX NC. 5134537147 P. 04

Centers for Disease Control and Prevention NationaS institute for Occupational Safety and Health interim Air Sampling Report Friday, September 21, 2001

Investigators from the National losUeute for Occupationtd Safety and Health (NlOSH) collected air samples in areas inunediatcly adjacent to the debris pDe and on personnel actively involved in rescue efforts in the vicinity of the debris pile to characterize potential exposures. Below are the intsrim sampling; results for Friday, September 21,2001.

Air Samples

• 4,5 persona! and 6 area air samples were coHeOed by NYDOH contractors 0 Personal sample 8-hour tune-weighied average concentrations were below 0.04 fibersZee as determined by PCM o AU area sample results were below 0.0i fibers/cc as determined by PCM

/ 'oSal Dvi't • 1S personal air samples were collected for total dust o Personal saaqjU 8-hour time-weighted average cancentrations were below 1,0 mg/xn"

o 7 personal and 4 area air samples were collected for metals , o Nothing of concern wa^ found regarding metal analysis

CiystatiiM al/cet » 2 personal air samples were collected for CtystalUns silica o Mo crystaUsne silica was detected on any of the air samples Carboit Manure • 5 rcal'timft personal breathing zone samples were collected for carbon monoxide o Most g4tour time-weighted average concentrattons were below 2 ppm (one was 32 ppm) o A single peak of §23 ppm was observed on a torch cutter

SEP. 2® '01 (KS:) 13 = 43 COMKONI CaT! ON M»: 58 PAC-K. 4

CITY_21MC100_008979143

NYC-WTC_OOO196414