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Appendix A
5/20/2009
6
7.3 Quality Control Sample (QCS) – For this procedure, the QCS can be any
certified dissolved sample which is obtained from an external source. If a
certified sample is not available, then use the standard material.
8.
SAMPLE COLLECTION, PRESERVATION, AND STORAGE
8.1
Water collected for TSS and/or TVS should be filtered through a
Whatman GF/F glass fiber filter (nominal pore size 0.7
µ
m), or
equivalent.
8.2
Samples should be placed into an aluminum foil pouch and should be
frozen at -20
°
C.
8.3
Frozen TSS/TVS samples may be stored longer than 28 days.
9.
QUALITY CONTROL
9.1
The laboratory is required to operate a formal quality control (QC)
program. The minimum requirements of this program consist of an
initial demonstration of laboratory capability and the continued analysis
of laboratory instrument blanks and calibration standard material,
analyzed as samples, as a continuing check on performance. The
laboratory is required to maintain performance records that define the
quality of data generated.
9.2
Initial Demonstration of Capability
9.2.1
The initial demonstration of capability (DOC) – is used to
characterize instrument performance (MDLs) and laboratory
performance (analysis of QC samples) prior to the analyses
conducted by this procedure.
9.2.2
Quality Control Sample (QCS/SRM) – When using this
procedure, a quality control sample is required to be analyzed
at the beginning and end of the run, to verify data quality and
acceptable instrument performance. If the determined
concentrations are not within
±
10% of the certified values,
performance of the determinative step of the method is
unacceptable. The source of the problem must be identified
and corrected before either proceeding with the initial
determination of MDLs or continuing with analyses.
9.2.3
Method Detection Limits (MDLs) – MDLs should be
established for TSS and TVS using a low level ambient water
sample. To determine the MDL values, analyzed seven
replicate aliquots of water. Perform all calculations defined in