| Organization
and Responsibility
Performance And Systems Audits
Corrective Action
QA/QC Reporting To Management
And Client
Quality Control Program
For The Analysis Of RCRA Samples
Other Quality Control Programs
At Consolidated Sciences
Definitions
QUALITY CONTROL
Analytical Quality Control
Spikes, Blanks and Duplicates
Field Duplicate Samples
Blanks
Surrogate Compounds
Quality Control Reference Sample
Check standard
Clean-Ups
Column Check Sample
Column Check Blank
Determinations of Instrument
Adjustment, Tuning, and Alignment
Calibration
Additional QC Requirements
for Inorganic Analysis
Additions Quality Control
Requirements for Organic Analysis
Identification of Compounds
Quantification of Compounds
Method Detection Limit
Data Reporting
Quality Control Documentation
Analytical Results
Calibration
Column Check
Extraction/Digestion
Surrogates
Matrix-Spiked Samples
Check Standard
Blank
Chromatograms
Quantitative Chromatogram Report
Mass Spectrum
Metal Interference Check
Sample Results and Detection Limit
QUALITY CONTROL REQUIREMENT
FOR EPA VOLATILE ORGANIC ANALYSIS METHODS AND REPORTING REQUIREMENTS
DEFINITIONS AND CALCULATIONS
GENERAL
ASPECTS OF QUALITY ASSURANCE AND QUALITY CONTROL
The
terms quality assurance and quality control are frequently
used interchangeably. In our context, quality control is used
specifically to refer to the routine laboratory application
of statistically based procedures to evaluate and control
the accuracy of results from analytical measurements. Quality
assurance refers to those activities necessary to generate
confidence in the results of sampling and measurement. In
general, this implies good laboratory practice. The implantation
of the quality assurance plan ensures the validity of the
data, which provides a reliable basis for decision-making.
A
comprehensive laboratory quality assurance program must be
based on careful attention to sample preservation techniques,
sample chain of custody, use and care of instruments, glassware,
chemicals data management, and laboratory personnel. Consolidated
Sciences follows the strict QA/QC guidelines discussed in
Test Methods for Evaluating Solid Waste Physical/Chemical
Methods, (proposed update) 1987, third edition, EPA, PB89-148076,
Washington, DC 20460 (SW 846) ; Methods for Chemical Analysis
of Water and Wastes, 1983, Environmental Monitoring and Support
Laboratory, Office of Research and Development, U.S. EPA,
Cincinnati, Ohio 45268 and referenced in:
- Guidelines
and Specification for Preparing Quality Assurance Program
Plans, September 20, 1980, Office of Monitoring Systems
and Quality Assurance, ORD, U.S. EPA, QAMS-004/80, Washington,
DC 20460.
- Interim
Guidelines and Specification for Preparing Quality Assurance
Project Plans, December 29, 1980, Office of Monitoring Systems
and Quality Assurance, ORD, U.S. EPA, QAMS-005/80, Washington,
DC 20460.
Organization
and Responsibility
As
part of the analytical program at Consolidated Sciences, activities
for the data generators data reviewers/approvers, and data
user/requesters must be clearly defined. The data generator
is typically the individual who carries out the analyses at
the direction of the data user/requestor or a designate within
or outside the laboratory. The reviewer/approver is responsible
for ensuring that the data produced by the data generator
meet agreed-upon specifications.
Responsibility
for data review is assigned to the Consolidated Sciences Quality
Assurance Officer or QA Manager. This individual has broad
authority has broad authority to approve or disapprove project
palns, specific analyses and final reports. The QA officer
is responsible for reviewing and advising on all aspects of
QA/QC, including:
Assisting
the data requester in specifying the QA/QC procedure to be
used during the program;
Making
laboratory evaluations and submitting audit samples to assist
in reviewing QA/QC procedures; and if problems are detected
taking corrective action. Consolidated Sciences primary mission
is laboratory analysis, however when large and complex amounts
of data are generated from both field and laboratory activities,
it is helpful to designate sampling monitors, analysis monitors,
and quality control/data monitors to assist in carrying out
the program or project: Consolidated Sciences can assist and
designate the sampling monitor who is responsible for field
activities. These duties include:
-
Determining (with the analysis monitor) appropriate sampling
equipment and sample containers to minimize contamination
-
Ensuring that sample are collected, preserved, and transported
as specified in the work plan
-
Checking that all sample documentation (labels, field notebooks,
chain-of-custody records, packing lists) is correct and
transmitting that information, along with the samples, to
the analytical laboratory.
The
analysis monitor is responsible for laboratory activities.
These include:
-
Training and qualifying personnel in specified laboratory
QC and analytical procedures, prior to receiving samples
-
Receiving samples from the field and verifying that incoming
samples correspond to the packing list or chain-of-custody
sheet; and verifying that laboratory QC and analytical procedures
are being followed as specified in the work plan, reviewing
sample and QC data during the course of analyses and, if
questionable data exist, determining which repeat samples
or analyses are needed.
The
quality control and data monitor is responsible for QC activities
and data management. These include:
Maintaining records of all incoming samples, tracking those
samples through subsequent processing and analysis, and ultimately,
appropriately disposing of those samples at the conclusion
of the program;
Preparing
quality control samples for analysis prior to and during program;
Preparing
QC and sample data for review by the analysis coordinator
and the program manager; and,
Preparing
QC and sample data for transmission and entry into a computer
database, if appropriate.
Performance
And Systems Audits
The
Consolidated Sciences QA/QC officer may carry out performance
and/or systems audits to ensure that data of known defensible
quality are produced.
Systems
audits are qualitative evaluations of all components of field
and laboratory quality control measurement system, and they
determine if the measurement systems are being used appropriately.
The audits may be carried out before all systems are operational,
during the program, or after the completion of the program.
Such audits typically involve a comparison of the activities
given in the QA/QC plan with those actually scheduled or performed.
A special type of systems audit is the data management audit.
This audit addresses only data collection and management activities.
The
performance audit is a quantitative evaluation of the measurement
systems of a program. It requires testing the measurement
systems of a program. It requires testing the measurement
systems with samples of known composition or behavior to evaluate
precision and accuracy. The performance audit is carried out
by or under the auspices of the QA office without the knowledge
of the analyst. Since this is seldom achievable, many variations
are used that increase the awareness of the analyst as to
the nature of the audit material.
Corrective
Action
Corrective
action procedures should be addressed in the program plan
project. These should include the following elements:
The
EPA predetermined limits for data acceptability beyond which
corrective action is required;
Procedures
for corrective action; and,
For
each measurement system, identification of the individual
responsible for approving the corrective action, if necessary.
The
need for corrective action may be identified by system or
performance audits or by standard QC procedures. The essential
steps in the corrective action system are:
-
Identification and definition of the problem
-
Assignment of responsibility for investigating the problem
-
Investigation and determination of the cause of the problem
-
Determination of the corrective action to eliminate the
problem
-
Assigning and accepting responsibility for implementing
the corrective action
-
Implementing the corrective action and evaluating its effectiveness
-
Verifying that the corrective action has eliminated the
problem
The
QA officer should ensure that these steps are taken and that
the problem that led to the corrective action has been resolved.
QA/QC
Reporting To Management And Client
QA
project program or plans should provide a mechanism for periodic
reporting to management (or to the data user) on the performance
of the measurement system and the data quality. Minimally,
these reports include:
-
Periodic assessment of measurement quality indicators, i.e.,
data accuracy, precision and completeness
-
Results of performance audits
-
Results of system audits
-
Significant QA problems and recommended solutions
The
final report for each project or data set includes a separate
QA section which summarize data quality information.
Quality
Control Program For The Analysis Of RCRA Samples
A
RCRA required analytical quality control program at Consolidated
Sciences supplies additional information that can be used
to:
-
Evaluate the accuracy and precision of analytical data in
order to establish the quality of the data
-
Provide an indication of the need for corrections to the
analytical system, when comparison with existing regulatory
of program criteria or data trends shows that activities
must be changed or monitored to a different degree
-
To determine the effect of corrections to the analytical
system
Other
Quality Control Programs At Consolidated Sciences
Other
guidance on Quality Assurance management and organization
is available from the Agency and professional organizations
such as ASTM, AOAC, APHA and FDA.
Definitions
ACCURACY:
Accuracy is the nearness of a measurement or the mean (x)
of a set of measurements to the true value. Accuracy is assessed
by means of reference samples and percent recoveries.
ANALYTICAL
BATCH: The basic unit for analytical quality control
is the analytical batch is defined as samples that are analyzed
together with the same method sequence and the same lots of
reagents and with the manipulations common to each sample
within the same time period or in continuous sequential time
periods. Samples in each batch should be of similar composition
(e.g. ground waste, sludge, ash, etc.)
BLANKS:
-
CALIBRATION BLANK: Usually an organic or
aqueous solution that is as free of the analyte as possible
and prepared with the same volume of chemical reagents used
in the preparation of the calibration standards and diluted
to the appropriate volume with the same solvent (water or
organic) used in the preparation of the calibration standard.
The calibration blank is used to give the null reading for
the instrument response versus concentration calibration
curve. One calibration blank should be analyzed with each
analytical batch, or every 20 samples, whichever is greater.
-
EQUIPMENT BLANK: usually an organic or
aqueous solution that is as free of analyte as possible
and is transported to the site, opened in the field, and
poured over or through the sample collection device, collected
in a sample container, and returned to the laboratory. This
serves as a check on sampling device cleanliness. One equipment
blank should be analyzed with each analytical batch, or
every 20 samples, whichever is greater.
-
FIELD BLANK: Usually an organic or aqueous
solution that is as free or analyte as possible and is transferred
from one vessel to another at the sampling site and preserved
with the appropriate reagents. This serves as a check on
reagent and environmental contamination. One field blank
should be analyzed with each analytical batch, or every
20 samples, whichever is greater.
-
REAGENT BLANK: Usually an organic or aqueous
solution that is as free of as possible and contains all
the reagents in the same volume as used in the processing
of the samples. The reagent blank must be carried through
the complete sample preparation procedure and contains the
same reagent concentrations in the final solution as in
the sample solution used for analysis. The reagent blank
is used to correct for possible contamination resulting
from the preparation or processing of the sample. One reagent
blank should be prepared for every analytical batch, or
for every 20 samples, whichever is greater.
-
TRIP BLANK: Usually an organic or aqueous
solution that is as free of analyte as possible and is transported
to the sampling site and returned to the laboratory without
being opened. This serves as a check on sample contamination
originating from sample transport, shipping, and from the
site conditions. One trip blank should be analyzed with
each analytical batch, or every 20 samples, whichever is
greater.
-
CHECK STANDARD: A material of known composition
that is analyzed concurrently with test samples to evaluate
a measurement process. An analytical standard that is analyzed
to verify a standard should be analyzed with each analytical
batch, or every 20 samples, whichever is greater.
MATRIX
SPIKE: A Matrix Spike is employed to provide a measure
of accuracy for the method used in a given matrix. A matrix
spike analysis is performed by adding a predetermined quantity
of stock solutions of certain analytes to a sample matrix
prior to sample extraction/digestion and analysis. The concentration
of the spike should be at the regulatory standard level or
the PQL for the method. When the concentration of the analyte
in the sample is greater than 0.1%, no spike of the analyte
is necessary.
MDL:
The method detection limit (MDL) is defined as the minimum
concentrating of a substance that can be measured and reported
with 99% confidence that the analyte concentration is greater
than zero and is determined from analysis of a sample in a
given matrix containing the analyte.
PRECISION:
Precision is the agreement between a set of replicate measurements
with out assumption or knowledge of the true value. Precision
is assessed by means of duplicate/replicate sample analysis.
RCRA:
The Resource Conservation And Recovery Act.
REAGENT
GRADE: Analytical reagent (AR) grade, ACS reagent
grade, and reagent grade are synonymous terms for reagents
that conform to the current specifications of the Committee
on Analytical Reagents of the American Chemical Society.
SAMPLES:
The following diagram illustrates the difference between duplicate
and replicate samples.
DUPLICATE
SAMPLES: Duplicate samples are two separate samples
taken from the same source (i.e. in separate containers and
analyzed independently).
ENVIRONMENTAL
SAMPLES: An environmental sample of field sample
is a representative sample of any material collected from
any source of which determination of composition or contamination
is requested or required.
Drinking Water: Delivered water (treated or untreated) designated
as potable water.
Water/Waste water: Raw source waters for public drinking water
supplies, ground waters, municipal influents/effluents, and
industrial influents/effluents.
Sludge:
Municipal sludges and industrial sludges.
Waste:
Aqueous and non-aqueous liquid wastes, chemical solids,
contaminated soils, and industrial liquid and solid wastes.
REFERENCE
SAMPLE: A Sample prepared from an independent standard
at a concentration other than that used for calibration, but
within the calibration range. An independent standard is defined
as a standard composed of the analyte (s) of interest from
a different source than that used in the preparation of standards
for use in the standard curve. A quality control reference
sample is intended as a independent check of technique, methodology,
and standards and should be run with every analytical batch
or every 20 samples, whichever is greater. This is applicable
to all organic and inorganic analyses.
REPLICATE
SAMPLES: Replicate samples are two aliquots taken
from the same sample container and analyzed independently.
In cases where aliquoting is impossible, as in the case of
volatiles, duplicate samples must be taken for the replicate
analysis.
STANDARD
CURVE: A standard curve is a curve that plots concentrations
of known analyte standards versus the instrument response
to the analyte. Calibration standards are prepared by diluting
the stock analyte solution in graduated amounts that cover
the expected range of the sample being analyzed. Standards
should be prepared at the frequency specified in the appropriate
section. The calibration solvent must be prepared using the
same type of acid or solvent and at the same concentration
as will result in the samples following sample preparation.
This is applicable to organic and inorganic chemical analyses.
SURROGATE:
Surrogates are organic compounds that are similar to analytes
of intereset in chemical composition, extraction, and chromatography,
but which are not normally found in environmental samples.
These compounds are spiked into all blanks, calibration and
check standard, samples (including duplicates and QC reference
samples) and spiked samples prior to analysis. Percent recoveries
are calculated for each surrogate.
WATER:
Any reference to water in a Chapter or Method refers to ASTM
Type II reagent water (unless otherwise specified) which is
free of contaminants that may interfere with the analytical
test in question.
QUALITY
CONTROL
The
procedures indicated below are to be performed for all analyses.
Specific instructions relevant to particular analyses are
given in the pertinent analytical procedures in SW846.
Field Quality Control (When requested of Consolidated Sciences
or to guide clients).
The sampling component of the Quality Assurance Program Plan
(QAPP) shall include as appropriate:
-
Reference to or incorporation of accepted sampling techniques
in the sampling plan
-
Procedures for documenting and justifying and field actions
contrary to the accepted techniques
-
Documentation of all pre-field activities such as equipment
check-out, calibrations, and container storage and preparation
-
Documentation of field measurement quality control data
(quality control procedures for such measurements shall
be equivalent or corresponding laboratory QC procedures)
-
Documentation of field activities
-
Documentation of post-field activities including sample
shipment and receipt, field team de-briefing and equipment
check-in
-
Generation of quality control samples including field duplicate
samples, gield blanks, equipment blanks and trip blanks
-
The use of these samples in the context of data evaluation,
with details of the methods employed (including statistical
methods) and of the criteria upon which the information
generated will be judged
Analytical
Quality Control
A
quality control operation or component is only useful if it
can be measured or documented. The following components of
analytical quality control are related to the analytical batch.
The procedures described are intended to be applied to chemical
analytical procedures.
Consolidated
Sciences shall retain all quality control data and records
required by these sections for three years from the time the
results are reported. The data is available to the client
or enforcement officials upon request.
Spikes,
Blanks and Duplicates
General
Requirements: These procedures shall be performed at
least once with each analytical batch with a minimum of once
per twenty samples.
Matrix-Spiked
Samples: A matrix-spiked sample shall be analyzed with
every analytical batch, or every 20 samples, whichever is
more frequent. The sample shall be spiked with the analyte
(s) of interest (see the appropriate SW 846 method). The sample
to be spiked should be typical or representative of the batch.
Ideally, it should be an intermediate between the cleanest
and the most contaminated sample based on the best information
available. It is recommended that the spike be made in a replicate
of one of the field duplicate samples. The procedure is applicable
to all organic or inorganic chemical analytes.
Field
Duplicate Samples
Field
Duplicate samples shall be analyzed with every analytical
batch, or every 20 samples, whichever is greater. This procedure
is applicable to all organic or inorganic chemical analytes.
Blanks
Each
batch shall be accompanied by the reagent blank. The reagent
blank shall be carried through the entire analytical procedure.
Surrogate
Compounds
Every
blank, standard, and environmental sample (including duplicates,
QC reference samples, and check standards) shall be spiked
with surrogate compounds prior to purging or extraction. Surrogates
shall be spiked into samples according to the appropriate
analytical methods. Surrogate spike recoveries shall fall
within the control limits set by the laboratory (in accordance
with procedures specified in the method or within + 20%) for
samples falling within the quantification limits without dilution.
Dilution of samples to bring the analyte concentration into
the linear range of calibration may dilute the surrogates
bellow the quantification limit; evaluation of analytical
quality then will rely on the quality control embodied in
the check, spiked and duplicate spiked samples. This is applicable
only to organic analyses.
Quality
Control Reference Sample
A
quality control reference sample is a sample prepared from
an independent standard at a concentration other than that
used for calibration, but within the calibration range. An
independent standard is defined as a standard composed of
the analytes of interest from a different source than that
used in the preparation of standards for use in the standard
curve. A quality control reference sample is intended as an
independent check of technique, methodology, and standards
and should be run with every analytical batch or every 20
samples, whichever is greater. This is applicable to all organic
and inorganic analyses.
Check
standard
A
standard of known concentration prepared by the analyst to
monitor and verify instrument performance on a daily basis.
Clean-Ups
Quality
control procedures described here are intended for absorbent
chromatography and back extractions applied to organic extracts.
All batches of adsorbents (Florisil, Alumina, Silica gel,
etc.)
Column
Check Sample
The
elution pattern shall be reconfirmed with a column check of
standard compounds after activation or deactivating a batch
of absorbent. These compounds after activating or deactivating
a batch of adsorbent. These compounds shall be representative
of each elution fraction. Recovery as specified in the methods
is considered an acceptable column check. A result lower than
specified indicates that the procedure is not acceptable or
has been misapplied. This is applicable to organic analyses
only.
Column
Check Blank
The
column check blank shall be run after activation or deactivating
a batch of adsorbent. This is applicable only to organic analyses.
Determinations
of Instrument Adjustment, Tuning, and Alignment
Requirements
and procedures are instrument and method specific. Analytical
instrumentation shall be tuned and aligned in accordance with
requirements specific to the instrumentation procedures employed.
Individual determinative procedures shall be consulted. Criteria
for initial conditions and for continuing confirmation conditions
for methods within this manual are found in the appropriate
procedures. This is applicable to all organic and inorganic
analyses.
Calibration
Analytical
instrumentation shall be calibrated in accordance with requirements
specific to the instrumentation and procedures employed. Methods
6010, 7000 and 8000 as well as the appropriate analytical
procedures shall be consulted for criteria for initial and
continuing calibration.
Additional
QC Requirements for Inorganic Analysis
Standard
curves used in the determination of inorganic analytes shall
be prepared as follows:
Standard
curves derived from data consisting of one calibration blank
and three concentrations shall be prepared for each analyte.
The response for each prepared standard shall be based upon
the average of three replicate readings of each standard.
The standard curve shall be used with each subsequent analysis
provided that the standard curve is verified by using at least
one reagent blank and one standard at a level normally encountered
or expected in such samples. The response for each standard
shall be based upon the average of three replicate readings
of the standard. If the results of the verification are not
within + 10% of the original standard curve, a reference standard
should be employed to determine if the discrepancy is with
the standard or with the instrument. New standards should
also be prepared on a quarterly basis at a minimum. All data
used in drawing or describing the curve shall be so indicated
on the curve or its description. A record shall be made of
the verification. Standard deviations and relative standard
deviations shall be calculated for the percent recovery of
analytes from the spiked sample duplicates and from the check
samples. These values shall be established for the twenty
most recent determinations in each category.
Additions
Quality Control Requirements for Organic Analysis
The
following requirements shall be applied to the analysis of
samples by gas chromatography, liquid chromatography and gas
chromatography/mass spectrometry. The calibration of each
instrument shall be verified at frequencies specified in the
methods. A new standard curve must be prepared as specified
in the methods.
The tune
of each GC/MS System used for the determination of organic
analytes shall be checked with 4-Bromofluorobenzene (BFB)
for determination of volitiles and with decafluorotriphenylphosphine
(DFTPP) for determinations of any analytes. If the system
does not meet the required specification for one or more of
the required ions, the instrument must be returned and rechecked
before proceeding with sample analysis. The tune performance
check criteria must be achieved daily or for each 12 hour
operating period, whichever is more frequent.
Background
subtraction should be straightforward and designed only to
eliminate column bleed or instrument background ions. Background
subtraction actions resulting in spectral distortions for
the sole purpose of meeting special requirements are contrary
to the objectives of Qual;ity Assurance and are unacceptable.
For determinations
by HPLC or GC, the instrument calibration shall be verified
as specified in the methods.
Identification
of Compounds
Identification
of all analytes must be accomplished with authentic standard
of the analyte. When authentic standards are not available,
identification is tentative.
For gas
chromatographic determinations of specific analytes, the relative
retention time of the unknown must be compared with that of
an authentic standard. For compound confirmation, a sample
and standard shall be re-analyzed on a column of different
selectivity to obtain a second characteristic relative retention
time. Peaks must elute within daily retention time windows
to be declared a tentative or confirmed identification.
For gas
chromatographic/mass spectrometric determinations of specific
analytes, the spectrum of the analyte should conform to a
literature representation of the spectrum or to a spectrum
of the authentic standards.
Quantification
of Compounds
The procedures
for quantification of analytes are discussed in the appropriate
general procedures (7000, 8000) and the specific analytical
methods.
In some
situation in the course of determining metal analytes, matrix-matched
calibration standards may be required. These standards shall
be composed of the pure reagent, approximation of the matrix,
and reagent addition of major interference in the samples.
This will be stipulated in the procedures.
Estimation
of the concentration of an organic compound not contained
within the calibration standard may be accomplished by comparing
mass spectral response of the compound with that of an internal
standard. The procedure is specified in the methods.
Method
Detection Limit
For operational
purposes, when it is necessary to determine the method detection
limit in the sample matrix, the MDL defined shall be determined
by multiplying by 7 the standard deviation obtained from the
triplicate analyses of a matrix spike containing the analyte
of interest at a concentration three to five times the estimated
MDL.
Determine
the estimated MDL as follows:
Obtain
the concentration value that corresponds to:
- An
instrument signal/noise ration within the range of 2.5 to
5.0, or
- The
region of the standard curve where there is a significant
change is sensitivity, i.e., a break in the slope of the
standard curve
Determine
the variance (S2) for each analyte as follows:
Determine
the standard deviation (S) for each analyte as follows:
S
= (S2) ½
Determine
the MDL for each analyte as follows:
MDL
= t(n-1, 1-a = 0.99) (S)
where
MDL = t(n-1, 1-a = 0.99) = 6.965 for three replicates
as determined from the table of student’s values at
the 99% level.
Data
Reporting
The requirement
of reporting analytical results on a wet-weight or a dry weight
basis is dictated by factors such as: sample matrix; program
or regulatory requirement; and objectives of the analysis.
Analytical
results shall be reported with the percent moisture or percent
solid content of the sample.
Quality
Control Documentation
The following
sections list the QC documentation that comprises the complete
analytical package; this package can be obtained from Consolidated
Sciences upon request.
Analytical
Results:
- Analyte
concentration
- Sample
weight
- Percent
water (for non-aqueous samples when specified)
- Final
volume of extract or diluted sample
- Holding
times
Calibration:
- Calibration
curve or coefficients of the linear equation that describes
the calibration curve
- Correlation
coefficients of the linear equation which describes the
calibration curve
- Concentration/response
data (or relative response data) of the calibration check
standards, along with dates on which they were analytically
determined
Column
Check:
Results
of column chromatography check, with the chromatogram
Extraction/Digestion:
Date of
the extraction for each sample
Surrogates:
Amount
of surrogate spiked, and percent recovery of each surrogate
Matrix-Spiked
Samples:
Amount
spiked, percent recovery, and relative percent difference
for each compound in the spiked samples for the analytical
batch
Check
Standard:
Amount
spiked, and percent recovery of each compound spiked
Blank:
Identity
and amount of each constituent
Chromatograms:
All chromatograms
for reported results, properly labeled with:
- Sample
Identification
- Method
Identification
- Identification
of retention time of analyte on the chromatograms
Quantitative
Chromatogram Report:
Retention
time on analyte
Amount
injected
Area
of appropriate calculation of detection response
Amount
of analyte found
Date
and time of injection
Mass
Spectrum:
Spectra
of standards generated from authentic standards (one for each
report for each compound detected)
Spectra of analytes from actual analyses
Spectrometer identifier
Metal
Interference Check Sample Results and Detection Limit:
Analyte
detection limits with methods of estimation
Results of standard additions
Results of serial dilutions
Instrument detection limits |
