Milestone DMA-80 evo - 8.4 QUALITY CONTROL

Milestone Srl MA213-003 – DMA-80 EVO – User Manual
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boat holder. Then run Boat holder cleaning
method. Repeat the test if necessary.
Contamination of sample boats Clean the boats as explained in the dedicated
chapter of this manual. If the contamination grade
is very high and it can not be removed, then replace
the boats.
Measurement of critical or unknow samples with
very high Hg content or generating big black fumes
Clean catalyst and amalgamator tube using Clean
water or Initialization method. Several runs could
be necessary.
If the blanks are still high, then replace catalyst and
amalgamator.
If after that the contamination is still present, then
it could have involved the cuvette: In this case
contact Milestone technician for a cleaning of the
cells.
Contamination from environment or gas carrier Move the machine in another room or eliminate the
cause of contamination (if possible).
Change gas bottle or in case of air compressor
check the filters.
8.4 QUALITY CONTROL
8.4.1 How to set up a QC program
The QC program is prepared and overseen by the Laboratory Manager, the QC Chemist, and the Scientific
Advisor.
QC protocol
Procedure
Frequency
Control Standards
The stability of the instrument calibration
is checked during the run by analysis of
the control standards.
Checked every 10 samples
Blanks
Method blanks are analyzed to confirm
the absence of contamination.
With each sample batch or one per 20
samples(5%) for each matrix
Duplicates
Duplicates are analyzed to check
method and stability and performance
With each sample batch or one per 20
samples(5%) for each matrix
Matrix Spikes
Sample matrix effects are checked by
spiking samples with a known amount of
standard and subsequently measuring
the recovery of the analyte in the
sample.
With each sample batch or one per 20
samples(5%) for each matrix
Standard Reference
Materials
Certified standards are used as control
samples to check the method
performance in the matrix.
For each matrix
All values shall be documented, maintained, and available for easy reference and inspection.
8.4.2 Acceptance Criteria for QC Samples
For more details refer to EPA method 7473.