Carpet mastic asbestos analysis results letter, December 2002

NYC 9/11 Public Portal Document

EMSLNYCNOBCHTFIELDSOP 200,0 Revison 1 February, 2002

6.0 DEFINITIONS: Working Magnification: The magnification at which analysis should be performed

Fiber Criteria: The attributes, size and shape, that a'structure must display in • order to be counted.

Sizing of Fibers: How the size of a structure needs to be recorded on the worksheet. For AHERA, a check is placed in a column according to a structure being < or > 5µm length. For EPA Level II, the actual length and width will need to be recorded.

Required EDX: The frequency at which structures need to be analyzed by EDX. For AHERA, each structure, which will cause the sample to exceed 70str/mm2 will need. EDX analysis. In the case of AHERA samples, this usually equates to the first four structures. For the analysis of water under 100.2, The x-ray spectrum for each type of asbestos observed for each set of samples from the. same source or a minimum of every fifth sample analyzed must be recorded.

Required Diffraction Patterns: The frequency at which structures need to be analyzed by SAED. .

Stopping Rules: The criteria required before analysis can be suspended.

• Required Analytical Sensitivity: The criteria required for the number of grid openings to be analyzed. AHERA requires an A.S. of 0.005str/cc so a sample with 1200 liters being analyzed on 0.0129 mm2 grid opening will require 5 openings for analysis.

Laboratory Blanks: A blank filter supplied by the lab, which is prepped along side. of the samples to test for contamination. This section states if a laboratory blank is required and if the blank will need to. be analyzed at the time of sample analysis.

Required Filters: The type of filter that the sample is to be taken on or filtered through.

Pass / Fail Limit: The level or concentration at which a sample or set of samples is past acceptable limits. '

Quality Control: The steps 'to follow for QC. (S= Intra Analyst; D= Inter Analyst; SR=lntra Analyst Reprep, DRI=Inter Analyst Reprep, Inter Laboratory; V= Verified, B=Blanks).

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