Ambient Dust Sampling Protocol Near WTC, Oct 2001

NYC 9/11 Public Portal Document

****DRAFT Version 10, October 29, 2001****

At least two field blanks (or 10% of samples submitted, whichever is greater) per sample location will be submitted with the air samples. Blank cassettes should be opened at the same time as the sample cassettes are opened (just prior to sampling). Blank cassettes and their covers should be stored in a clean area (e.g., closed bag or box) with the covers from the sampling cassettes during the sampling period.

Each air sampling pump will be calibrated with a representative sampling device in-line before and after sample collection. Sample flow rates will be documented in the sampling log. The average of pre- and post-calibration flow rates will be used as the sample flow rate, for sample volume calculations.

Dust samples will be collected using the EPA Environmental Response Team (ERT) indoor dust sampling standard operating procedure (SOP). Duplicate samples are not feasible with indoor surface dust sample collection. Co-located samples (samples collected from adjacent areas of the floor) will be collected in 10% of the indoor surface dust sample locations. While not a true duplicate, evaluation of the results will provide some information on the variability of contaminants in the dust.

Samples should not be packaged in untreated polystyrene-electrostatic forces may cause fiber loss from some sample filters.

Chain of custody will be established and maintained throughout sample collection, transport, and analysis of the samples. Laboratory analysis shall follow all method-required quality assurance and quality control procedures.

All samples collected, unless analyzed with destructive methods, will be archived until further notice.

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