NYC-WTC_000219925

NYC 9/11 Public Portal Document 1 Search -1 Result - APPENDIX A TO SUBPART E - INTERIM TRANSMISSION EL... Page 34 of 38

1876 and/or RM year Dev. 8410 (measure of accuracy and comparability) Data entry review Each sample 95% (data validation and measure of completeness) Record and verify 1 per 5 samples 80% accuracy ID electron dif­ fraction pattern of structure Calculations and Hand calculation of 1 per 100 samples 85% data reduction automated data reduction procedure or in­ dependent recal­ culation of hand- calculated data

1. When the samples arrive at the laboratory, check the samples and documentation for completeness and requirements before initiating the analysis.

2. Check all laboratory reagents and supplies for acceptable asbestos background levels.

3. Conduct all sample preparation in a clean room environment monitored by laboratory blanks and special testing after cleaning or servicing the room.

4. Prepare multiple grids of each sample.

5. Provide laboratory blanks with each sample batch. Maintain a cumulative average of these results. If this average is greater than 53 f/mm (2) per 10 200-mesh grid openings, check the system for possible sources of contamination.

6. Check for recovery of asbestos from cellulose ester filters submitted to plasma asher.

7. Check for asbestos carryover in the plasma asher by including a blank alongside the positive control sample.

8. Perform a systems check on the transmission electron microscope daily.

9. Make periodic performance checks of magnification, electron diffraction and energy dispersive X-ray systems as set forth in Table III of Unit III.K.

10. Ensure qualified operator performance by evaluation of replicate counting, duplicate analysis, and standard sample comparisons as set forth in Table III of Unit III.K.

11. Validate all data entries.

12. Recalculate a percentage of ail computations and automatic data reduction steps as specified in Table III.

http://lexis/research/retrieve?_m=el35f2ca3d266867e53d261dG205722&_fmtstr=FULU... 02/04/2002 CITY_21MC100_012558698

NYC-WTC_000219958