Code of Maine Rules
10 - DEPARTMENT OF HEALTH AND HUMAN SERVICES
144 - DEPARTMENT OF HEALTH AND HUMAN SERVICES - GENERAL
Chapter 263 - MAINE COMPREHENSIVE AND LIMITED ENVIRONMENTAL LABORATORY ACCREDITATION RULE
Section 144-263-11 - QUALITY CONTROL CRITERIA
Universal Citation: 10 ME Code Rules ยง 144-263-11
Current through 2024-38, September 18, 2024
A. Quality control criteria for chemistry
1.
Scope
a. This section applies to laboratories
performing testing under the inorganic chemistry, metals, volatile organic
compounds and other organic compounds test categories unless otherwise
indicated.
b. All requirements in
this Section must be incorporated into the laboratory's procedures, unless
otherwise directed by the approved method. The quality control requirements
specified by the laboratory's standard operating procedures must be
followed.
c. All quality control
measures must be assessed and evaluated on an ongoing basis and quality control
acceptance criteria must be used to determine the validity of the
data.
2. Method blanks
a. A method blank must be processed along
with and under the same conditions as the associated samples to include all
steps of the analytical procedure.
b. The method blank must be analyzed at a
minimum of one per batch.
c.
Procedures must be in place to determine whether a method blank is
contaminated. Any affected samples associated with a contaminated method blank
must be reprocessed for analysis or the results must be reported with
appropriate data qualifying codes.
d. Each contaminated method blank must be
critically evaluated as to the nature of the interference and the effect on the
analysis of each sample within the batch. The source of contamination must be
investigated, and measures taken to minimize or eliminate the problem. Affected
samples must be reprocessed or data must be appropriately qualified if:
(i) The concentration of a target analyte in
the blank is at or above the reporting limit as established by the test method
or by regulation and is greater than one-tenth of the amount measured in any
sample; or
(ii) The blank
contamination otherwise affects the sample results according to test method
requirements or the individual project data quality objectives.
3. Laboratory control
sample (LCS)
a. An LCS must be used to
evaluate the performance of the total analytical system, including all
preparation and analysis steps. Results of the LCS must be compared to
established criteria and, if found to be outside of established criteria, must
indicate that the analytical system is "out of control." Any affected samples
associated with an out of control LCS must be reprocessed for reanalysis or the
results must be reported with appropriate data qualifying codes.
b. An LCS must be analyzed at a minimum of
one per preparation batch, except for:
(i)
Analytes for which no spiking solutions are available; or
(ii) When the method specifically states that
the LCS is not necessary.
c. All analyte concentrations must be within
the calibration range of the instrument calibration. The components to be
spiked must be as specified by the permit, program or rule requirement. In the
absence of permit, program, rule or method requirements, the laboratory must
spike as follows:
(i) For those components
that interfere with an accurate assessment, such as spiking simultaneously with
technical chlordane, toxaphene and PCBs, the spike must be chosen that
represents the chemistries and elution patterns of the components to be
reported.
(ii) The number of
analytes selected is dependent on the number of analytes reported. The analytes
selected for the spiking solution must be representative of all analytes
reported. The following criteria must be used for determining the minimum
number of analytes to be spiked:
(1) For
methods that include one to ten analytes, spike all components.
(2) For methods that include 11 to 20
analytes, spike at least ten components or 80 percent of the analytes,
whichever is greater.
(3) For
methods with more than 20 analytes, spike at least 16 components.
d. The results of the
analytes included in the LCS are calculated in percent recovery or a measure
that allows comparison to established acceptance criteria. The laboratory must
document the calculation. The individual LCS is compared to the acceptance
criteria as published in the approved method or as specified in
client-specified assessment criteria within a permit, program or rule
requirement. When there are no established criteria, the laboratory must
determine its own criteria and document the method used to establish the limits
or utilize client-specified assessment criteria within a permit, program or
rule requirement.
e. An LCS that is
determined to be within the criteria effectively establishes that the
analytical system is in control and validates system performance for the
samples in the associated batch. Samples analyzed along with an LCS determined
to be "out of control" must be considered suspect. The samples must be
reprocessed and reanalyzed or the data must be reported with appropriate data
qualifying codes.
4.
Matrix spike and matrix spike duplicates
a.
The frequency of the analysis of matrix spikes and matrix spike duplicates must
be determined as part of a systematic planning process or as specified by the
required approved method, when applicable. Where no requirement is stated, the
laboratory must prepare and analyze at least one matrix spike and one matrix
spike duplicate with each batch, unless the lab has not been provided a
sufficient sample amount. The matrix spikes must be prepared from samples
contained in the batch.
b. For a
matrix spike, the components to be spiked must be as specified by the approved
method or permit, program or rule requirement. In the absence of specified
spiking components, the laboratory may follow client instructions and then must
document its criteria for quality control. In the absence of client
instruction, the laboratory must spike as follows:
(i) For those components that interfere with
an accurate assessment, such as spiking simultaneously with technical
chlordane, toxaphene and PCBs, the spike must be chosen that represents the
chemistries and elution patterns of the components to be reported.
(ii) The number of analytes selected is
dependent on the number of analytes reported. The analytes selected for the
spiking solution must be representative of all analytes reported. The following
criteria must be used for determining the minimum number of analytes to be
spiked:
(1) For methods that include one to
ten analytes, spike all components.
(2) For methods that include 11 to 20
analytes, spike at least ten components or 80 percent of the analytes,
whichever is greater.
(3) For
methods with more than 20 analytes, spike at least 16 components.
c. The results from
matrix spikes and matrix spike duplicates must be expressed as percent
recovery, relative percent difference, absolute difference or other appropriate
measure. Results of matrix spikes and matrix spike duplicates must be compared
to the acceptance criteria as published in the approved method or as specified
in client-specified assessment criteria within a permit, program or rule
requirement. When there are no established criteria, the laboratory must
determine its own criteria and document the procedure used to establish the
limits or utilize client-specified assessment criteria within a permit, program
or rule requirement.
5.
Surrogate spikes
a. This sub-section applies
to the analysis of organic compounds.
b. Except when the matrix precludes their use
or when not available, surrogate compounds must be added to all samples,
standards and blanks for all appropriate test methods before sample preparation
or extraction.
c. Surrogate
compounds must be chosen to represent the various chemistries of the analytes
in the method. When specified, the surrogates mandated in the method must be
used.
d. The results from surrogate
spikes must be expressed as percent recovery. Results of surrogate spikes must
be compared to the acceptance criteria as published in the approved method.
When there are no established criteria, the laboratory must determine its own
criteria and document the method used to establish the limits or utilize
client-specified assessment criteria within a permit, program or
rule.
6. Internal
standards
a. This sub-section applies to the
analysis of organic compounds.
b.
When internal standards are recommended or required by the test method, such as
mass spectrometry techniques, a laboratory must add the internal standards to
all samples, standards, blanks and QC samples before analysis.
c. When specified in the test method, a
laboratory must use the internal standards mandated in the test method. If
internal standards are not recommended in the method, then the analyst must
select one or more internal standards that are similar in analytical behavior
to the compounds of interest and not expected to be found in the samples
otherwise.
d. A laboratory must
monitor and document the results from analysis of internal standards.
e. Results of internal standards must be
compared to the acceptance criteria as published in the approved method. When
there are no established criteria, the laboratory must determine its own
criteria and document the procedure used to establish the limits or utilize
client-specified assessment criteria within a permit, program or rule
requirement.
7. Method
detection limits (MDL)
a. Each laboratory must
experimentally determine the MDL for analysis of each analyte, if applicable,
for each matrix in which the laboratory is accredited.
b. The laboratory must document its procedure
for determining the MDL.
c. MDL
procedures must be conducted as follows:
(i)
Drinking Water Program methods: The laboratory must use the procedure for
determining the MDL that is described in the analytical method being used. If
the analytical method does not include a procedure for the determination of
MDLs, then the laboratory must determine the MDL using the procedure described
in 40 CFR Part 136 , Appendix B, updated in the Annual Edition of July 1,
2022.
(ii) Wastewater Program
methods: The laboratory must use the procedure for determining the MDL using
the procedure described in 40 CFR Part 136 , Appendix B, updated in the Annual
Edition of July 1, 2022.
d. Calculations and supporting documentation
used in determining limits must be available for inspection.
e. MDLs must be expressed in appropriate
method reporting units.
f. The
laboratory must achieve the MDLs required by the applicable regulations or
program.
g. Sample preparation and
analysis for the MDL calculation must be made over a period of at least three
days.
h. MDLs must be determined as
part of a laboratory's initial demonstration of capability to perform an
analysis, when there is a change in the test method that may affect how the
test is performed, when a change in instrumentation occurs that affects the
sensitivity of the analysis, and as required by an analytical method.
i. MDLs must be determined using analysts and
instruments that are representative of those used in the performance of
analyses.
j. The laboratory must
verify its capability to analyze reporting level standards on an ongoing basis
through the analysis of reporting level verification standards that utilize all
preparation and analytical steps as required for samples.
k. The accreditation officer must not require
a detection limit study for any component for which spiking solutions or
quality control samples are not available.
8. Reporting limits (RL)
a. The laboratory must determine the minimum
RL for analysis of each analyte for each matrix in which the laboratory is
accredited. The laboratory must document the procedure used to determine the
minimum reporting level. The laboratory must verify the minimum reporting level
on an ongoing basis.
b. The RLs
must be greater than the MDLs.
c. A
laboratory must verify the RL each time the instrument is calibrated or monthly
at a minimum. The laboratory must analyze a verification standard prepared at a
concentration equal to or below the RL, prepared using all the steps of the
procedure. The percent recovery of the standard must fall within plus or minus
40 percent of the true value, unless otherwise stated in the method.
d. If the percent recovery of the RL
verification standard is outside the acceptance criteria, a laboratory must
elevate the reporting limit for the associated samples to the concentration of
the lowest point, above the zero blank, that meets the criteria in Section
8. The laboratory must report all
samples analyzed after the failed RL check using the elevated RL until a new
calibration curve and RL verification standard meet the acceptance
criteria.
9. Selectivity
a. This sub-Section applies to organic
compounds.
b. Absolute retention
time and relative retention time aid in identifying components in
chromatographic analyses and evaluating the effectiveness of a chromatographic
medium to separate constituents. A laboratory must develop and document
acceptance criteria for retention time windows if the acceptance criteria are
not specified in the approved method.
c. A confirmation must be performed to verify
the compound identification when positive results are detected in drinking
water. The confirmations must be performed on organic tests, such as
pesticides, herbicides or acid-extractable compounds or when recommended by the
analytical test method, except when the analysis involves the use of a mass
spectrometer or Fourier transform infrared spectrometer (FTIR). All
confirmations must be documented.
d. A confirmation must be performed to verify
the compound identification when positive results are detected in a sample from
a location that has not been previously tested. The confirmations must be
performed on organic tests, such as pesticides, herbicides or acid-extractable
compounds, or when recommended by the analytical test method, except when the
analysis involves the use of a mass spectrometer or FTIR. A confirmation is not
required on positive results for samples analyzed for diesel range organics and
gasoline range organics, Extractable Petroleum Hydrocarbons (EPH), Volatile
Petroleum Hydrocarbons (VPH) or Total Extractable Petroleum Hydrocarbons (TEPH)
under the Underground Storage Tank Program. All confirmations must be
documented.
e. A laboratory must
document acceptance criteria for mass spectral tuning. The laboratory must
ensure that the tuning criteria meet the specifications in the approved method
or as established by the client, whichever is more stringent.
10. Manual integrations
a. If the integrations are not calculated
exclusively by the equipment's software, a laboratory must document acceptable
use of manual integrations and must have in place a system for review of manual
integrations performed to verify adherence to the policies and procedures of
the laboratory.
11.
Consistent test conditions
a. A laboratory
must ensure that the test instruments consistently operate within the
specifications required of the application for which the equipment is
used.
b. A laboratory must ensure
that glass and plastic containers are cleaned so that they meet the sensitivity
of the test method. Any cleaning and storage procedures that are not specified
by the test method must be documented in laboratory records and the laboratory
SOPs manual.
B. Quality control criteria for bacteriology
1. Scope This Section applies to laboratories
performing tests under the bacteriological test category unless otherwise
indicated. All requirements in this Section must be incorporated into the
laboratory's procedures unless otherwise directed by the approved method. The
QC requirements specified by the laboratory's SOPs must be followed. All QC
measures must be assessed and evaluated on an ongoing basis and QC acceptance
criteria must be used to determine the validity of the data.
2. Sterility and Autofluorescence Checks
a. Each lot of pre-prepared, ready-to-use
media, including chromofluorogenic reagent and each lot of media prepared in
the laboratory must be checked for sterility. Chromofluorogenic media must also
be checked for autofluorescence. The media check must be run using a container
and water that has passed a sterility check. The analysis must be done before
first use of each lot of media.
b.
For filtration technique:
(i) A laboratory
must conduct one beginning and one ending sterility check for each filtration
unit used in a filtration series. The filtration series may include single or
multiple filtration units that have been sterilized before beginning the
series.
(ii) For pre-sterilized,
single-use funnels purchased, a sterility check must be performed on one funnel
per lot before use.
(iii) The
filtration series is considered ended when more than 30 minutes elapse between
successive filtrations.
(iv) During
a filtration series, filter funnels must be rinsed with three 20 to 30
milliliter portions of sterile rinse water after each sample
filtration.
(v) Laboratories must
insert a sterility blank after every ten samples per filtration unit or
sanitize filtration units by ultraviolet light after each sample
filtration.
c. For
pour-plate technique, a sterility check of the media must be made by pouring,
at a minimum, one uninoculated plate for each lot of pre-prepared, ready-to-use
media and one for each lot of media prepared in the laboratory.
d. Sterility checks on sample containers and
Quanti-Trays® must be performed on at least one
container for each lot of purchased, pre-sterilized containers. For containers
sterilized in the laboratory, a sterility check must be performed on one
container per sterilized batch, using nonselective growth media. Sample
containers used for chromofluorogenic methods must also be checked for
autofluorescence. The analysis must be done before first use.
e. A sterility check must be performed on
each batch of dilution water prepared in the laboratory and on each batch of
pre-prepared, ready-to-use dilution water using nonselective growth media. The
analysis must be done before first use.
f. At least one filter from each new lot of
membrane filters must be checked for sterility by filtering 20 to 30
milliliters of sterile dilution water through the filter and testing for
growth. The analysis must be done before first use.
3. Positive controls
Each pre-prepared, ready-to-use lot of media, including chromofluorogenic reagent, and each lot of media prepared in the laboratory must be tested with at least one pure culture of a microorganism known to elicit a positive reaction. This must be done before first use of each lot of media.
4. Negative controls
Each pre-prepared, ready-to-use lot of selective media, including chromofluorogenic reagent and each lot of selective media prepared in the laboratory must be analyzed with one or more known negative culture controls (e.g., non-target microorganisms) that should not grow on the test media, as appropriate to the method. This analysis must be done before first use of each lot of media.
5.
Test variability
For test methods that specify colony counts, such as methods using membrane filters or plated media, duplicate counts must be performed and documented monthly on at least one positive sample for each month that the test is performed. With respect to this test for variability, if the laboratory has two or more analysts, each analyst must count typical colonies on the same plate and counts must be within a ten-percent difference between analysts to be acceptable. In a laboratory with only one bacteriology analyst, the same plate must be counted twice by the analyst, with no more than a five-percent difference between the counts.
6. Method evaluation
A laboratory must demonstrate proficiency with the test method before first use, by comparison to a method already approved for use in the laboratory, by analyzing a minimum of ten spiked samples with a matrix representative of those normally submitted to the laboratory or by analyzing and passing one proficiency test series provided by an approved proficiency sample provider. The laboratory must maintain documentation of the proficiency demonstration, as long as the method is in use and for at least five years after the date of last use.
7. Test performance
To ensure that analytical results are accurate, those laboratories using commercially prepared media with manufacturer shelf-lives of greater than 90 days must run positive and negative controls each quarter, in addition to running these controls and sterility checks on each new lot of media.
8. Quality of
standards, reagents and media
a. Culture
media may be prepared from commercial dehydrated powders or may be purchased
ready-to-use, unless otherwise indicated in the approved method. Media may be
prepared by the laboratory from basic ingredients when commercial media are not
available or when it can be demonstrated that commercial media do not provide
adequate results. Media prepared by the laboratory from basic ingredients must
be tested for performance, such as for selectivity, sensitivity, sterility,
growth promotion and growth inhibition, before first use. Detailed testing
criteria information must be defined in the laboratory's SOPs manual or QA
manual.
b. Reagents, commercial
dehydrated powders and media must be used within the shelf life of the product.
The specifications of the reagent, powder or media must be documented according
to the laboratory's QA manual.
c.
Distilled, deionized or reverse-osmosis produced water that is free from
bactericidal and inhibitory substances must be used in the preparation of
media, solutions and buffers. The quality of the water must meet the
requirements as listed in Section 8.
d. Media, solutions and reagents must be
prepared, used and stored according to a documented procedure following the
manufacturer's instructions or the test method. Documentation for media
prepared in the laboratory must include the:
(i) Date of preparation;
(ii) Preparer's initials;
(iii) Type and amount of media
prepared;
(iv) Manufacturer and lot
number;
(v) Final pH of the media
after sterilization; and
(vi)
Expiration date.
e.
Documentation for media purchased pre-prepared and ready-to-use must include
the:
(i) Manufacturer;
(ii) Lot number;
(iii) Type and amount of media
received;
(iv) Date of
receipt;
(v) Expiration date of the
media; and
(vi) Verification of the
pH of the liquid.
9. Selectivity
a. To ensure identity and traceability,
reference cultures used for positive and negative controls must be obtained
from a recognized national organization.
b. Microorganisms may be single-use
preparations or cultures maintained by documented procedures that demonstrate
the continued purity and viability of the organism.
c. Reference cultures may be revived, if
freeze-dried or transferred from slants and sub-cultured once to provide
reference stocks. The reference stocks must be preserved by a technique that
maintains the characteristics of the strains. Reference stocks must be used to
prepare working stocks for routine work. If reference stocks have been thawed,
they must not be refrozen and reused.
d. Working stocks must not be cultured
sequentially more than five times and must not be sub-cultured to replace
reference stocks.
10.
Temperature measuring devices
a. Temperature
measuring devices such as liquid-in-glass thermometers, thermocouples and
platinum resistance thermometers used in incubators, autoclaves and other
equipment must be of the appropriate quality to meet specifications in the test
method.
b. The temperature
measuring devices must be graduated in 0.5°C increments (or 0.2°C
increments for tests which are incubated at 44.5°C) or less, except as
noted for hot air ovens and refrigerators. These devices must be calibrated
against thermometers from an accredited third party or a National Metrology
Institute (e.g., NIST), traceable to the SI, International System of Units. All
measurements must be recorded.
11. Autoclaves
a. The performance of each autoclave must be
evaluated initially by establishing its functional properties and performance
(e.g., heat distribution characteristics with respect to typical uses).
Autoclaves must meet specified temperature tolerances. Pressure cookers must
not be used for sterilization of growth media.
b. Demonstration of sterilization temperature
must be provided by use of a continuous temperature recording device or by use
of a maximum registering thermometer with every cycle. Appropriate biological
indicators must be used once per month to determine effective sterilization.
Temperature-sensitive tape must be used with the contents of each autoclave run
to indicate that the autoclave contents have been processed.
c. Records of autoclave operations must be
maintained for every cycle. Records must include: date, contents, maximum
temperature reached, pressure, time in sterilization mode, total run time
(which may be recorded as time in and time out) and operator's
initials.
d. Autoclave maintenance,
either internally or by service contract, must be performed annually or must
include a pressure check and calibration of the temperature device. Records of
the maintenance must be maintained in equipment logs.
e. The autoclave's mechanical timing device
must be checked quarterly against a stopwatch and the actual time elapsed must
be documented.
12.
Ultraviolet instruments
a. Ultraviolet (UV)
instruments used for sterilization must be tested quarterly for effectiveness
with an appropriate UV light meter or by plate counts on agar spread
plates.
b. Bulbs must be replaced
if output is less than 70 percent of original for light tests or if count
reduction is less than 99 percent for a plate containing 200 to 300
organisms.
13.
Incubators, water baths and ovens
a. The
stability and uniformity of temperature distribution and the time required
after test sample addition to reestablish equilibrium conditions in incubators
and water baths must be documented. Calibration-corrected temperature of
incubators and water baths must be documented twice daily, at least four hours
apart, on each day of use.
b. Ovens
used for sterilization must be checked for sterilization effectiveness monthly
with appropriate biological indicators. Records must be maintained for each
cycle and include the date, cycle time, temperature, contents and analyst's
initials.
14. Labware,
glassware and plasticware
a. A laboratory must
have a documented procedure for washing labware, if applicable. Detergents
designed for laboratory use must be used.
b. Glassware must be made of borosilicate or
other noncorrosive material, free of chips and cracks and must have readable
measurement marks.
c. Labware that
is washed and reused must be tested for possible presence of residues that may
inhibit or promote growth of microorganisms by performing the inhibitory
residue test annually and each time the laboratory changes the lot of detergent
or washing procedures.
d. At a
minimum, one piece of washed labware must be tested daily, each day of washing,
for possible acid or alkaline residue. Labware must be tested with a suitable
pH indicator (e.g., Bromothymol blue). Records of tests must be
documented.
15.
Quanti-Tray® sealer When the
Quanti-Tray® or
Quanti-Tray® 2000 test is utilized, the sealer
must be checked monthly by adding a dye (e.g., Bromocresol purple) to the
water. If the dye is observed outside of the wells, maintenance must be
performed, or another sealer utilized.
C. Quality control criteria for radiochemistry
1. Scope
a. This Section applies to laboratories
performing radiochemistry testing on environmental samples. All requirements in
this Section must be incorporated into the laboratory's SOPs unless otherwise
directed by the approved method.
b.
The quality control requirements specified by the laboratory's SOPs must be
followed. All quality control measures must be assessed and evaluated on an
ongoing basis and quality control acceptance criteria must be used to determine
the validity of the data.
2. Method blanks
a. A laboratory must analyze at least one
method blank per batch. The method blank result must be evaluated according to
the acceptance criteria in the laboratory's standard operating
procedures.
b. When the method
blank acceptance criteria are not met, a laboratory must take corrective
action. The occurrence of a failed method blank and the actions taken must be
noted in the laboratory report.
c.
In the case of gamma spectrometry, where the sample matrix is simply aliquoted
into a calibrated counting geometry, the method blank must be of similar
counting geometry that is empty or filled to similar volume with ASTM Type II
water to partially simulate gamma attenuation due to the sample
matrix.
d. A laboratory must not
subtract results of method blank analysis from the sample results in the
associated batch, unless permitted by the approved method. This requirement
does not preclude the application of any correction factor, such as instrument
background, analyte presence in tracer, reagent impurities, peak overlap or
calibration blank, to all analyzed samples, both program- or project-submitted
and internal QC samples. The correction factors must not depend on the required
method blank result in the associated analytical batch.
e. The method blank sample must be prepared
with similar aliquot size to that of the routine samples for analysis whenever
possible.
3. Laboratory
control sample
a. Laboratory control samples
must be performed at a frequency of one per batch. The results of the analysis
must be one of the QC measures to be used to assess the batch.
b. The laboratory control sample result must
be assessed against the specific acceptance criteria specified in the
laboratory SOPs. When the specified laboratory control sample acceptance
criteria are not met, the specified corrective action and contingencies must be
followed.
c. The occurrence of a
failed laboratory control sample acceptance criterion and the actions taken
must be noted in the laboratory report.
d. The activity of the laboratory control
sample must be:
(i) Two to ten times the MDL;
or
(ii) At a level comparable to
that of routine samples, if the sample activities are expected to exceed ten
times the MDL.
e. The
laboratory standards used to prepare the laboratory control sample must be from
a source independent of the laboratory standards used for instrument
calibration, if available.
f. The
laboratory control sample must be prepared by adding a known activity of target
analyte. When a radiochemical method, other than gamma spectroscopy, has more
than one reportable analyte isotope, such as Plutonium, Pu-238 and Pu-239,
using alpha spectrometry, only one of the analyte isotopes need be included in
the laboratory control sample. When more than one analyte isotope is added to
the laboratory control sample, each isotope must be assessed against the
specified acceptance criteria.
4. Matrix spikes
a. Matrix spikes must be performed at a
frequency of one per batch for those methods that do not utilize an internal
standard or carrier, for which there is a chemical separation process and when
there is sufficient sample to do so.
b. Gross alpha, gross beta and tritium
require matrix spikes for aqueous samples. The result of the analysis must be
one of the QC measures used to assess sample acceptability. The matrix spike
result must be assessed against the specific acceptance criteria specified in
the laboratory SOPs.
c. When the
specified matrix spike acceptance criterion is not met, the corrective actions
specified in the laboratory's SOPs must be followed. The occurrence of a failed
matrix spike acceptance criterion and the actions taken must be noted in the
laboratory report. The lack of sufficient sample aliquot size to perform a
matrix spike must also be noted in the laboratory report.
d. The activity of the analytes in the matrix
spike must be greater than 10 times the MDL.
e. The laboratory standards used to prepare
the matrix spike must be from a source independent of the laboratory standards
used for instrument calibration, if available.
f. The matrix spike must be prepared by
adding a known activity of target analyte. When a radiochemical method, other
than gamma spectroscopy, has more than one reportable analyte isotope, such as
Plutonium, Pu 238 and Pu 239, using alpha spectrometry, only one of the analyte
isotopes needs to be included in the matrix spike sample. When more than one
analyte isotope is added to the matrix spike, each isotope must be assessed
against the specified acceptance criteria.
g. When gamma spectrometry is used to
identify and quantitate more than one analyte isotope, the laboratory control
sample and matrix spike must contain isotopes that represent the low
(Americium-241), medium (Cesium-137) and high (Cobalt-60) energy range of the
analyzed gamma spectra. As indicated by these examples, the isotopes need not
exactly bracket the calibrated energy range or the range over which isotopes
are identified and quantitated.
h.
The matrix spike sample must be prepared with similar aliquot size to that of
the routine samples of analyses.
5. Tracer
a.
For those approved methods that allow or require the use of a tracer (e.g.,
internal standard), each sample result must have an associated tracer recovery
calculated and reported. The tracer recovery for each sample result must be one
of the QC measures used to assess the associated sample result
acceptance.
b. The tracer recovery
must be assessed against the specific acceptance criteria specified in the
laboratory SOPs. When the specified tracer recovery acceptance criteria are not
met, corrective actions specified in the laboratory's SOPs must be followed.
The occurrence of a failed tracer recovery and the corrective actions taken
must be noted in the laboratory report.
6. Carrier
a. For those approved methods that allow or
require the use of a carrier, each sample must have an associated carrier
recovery calculated and reported. The carrier recovery for each sample must be
one of the QC measures used to assess the associated sample result
acceptance.
b. The carrier recovery
must be assessed against the specific acceptance criteria specified in the
laboratory SOPs. When the specified carrier recovery acceptance criteria are
not met, the corrective actions specified in the laboratory's QA manual must be
followed. The occurrence of failed carrier recovery acceptance criteria and the
actions taken must be noted in the laboratory report.
7. Analytical variability; reproducibility
for radiochemistry testing
a. A laboratory
must analyze replicate samples at least once per batch when there is sufficient
sample to do so. The results of the analysis must be one of the QC measures
used to assess sample results acceptance. The replicate result must be assessed
against the specific acceptance criteria specified in the laboratory's
SOPs.
b. When the specified
replicate acceptance criteria are not met, the corrective actions specified in
the laboratory's SOPs must be followed. The occurrence of failed replicate
acceptance criteria and the actions taken must be noted in the laboratory test
results.
c. If sample
concentrations are expected to contain analytes of interest below three times
the detection limit, a laboratory may substitute replicate laboratory control
samples or replicate matrix spiked samples for replicate samples in above. The
replicate result must be assessed against the specific acceptance criteria
specified in the laboratory's SOPs. When the specified replicate acceptance
criteria are not met, the corrective actions specified in the laboratory's SOPs
must be followed. The occurrence of failed replicate acceptance criteria and
the actions taken must be noted in the laboratory test results.
8. Instrument calibration
a. Radiochemistry analytical instruments must
be calibrated prior to first use in sample analysis.
b. Calibration must be verified when:
(i) The instrument is serviced;
(ii) The instrument is moved; and
(iii) The instrument settings have been
changed.
c. The standards
used for calibration must have the same general characteristics (e.g.,
geometry, homogeneity and density) as the associated samples.
d. The calibration must be described in the
laboratory's SOPs.
9.
Continuing calibration verification
a.
Calibration verification checks must be performed using appropriate check
standards and monitored with control charts or tolerance charts to ensure that
the instrument is operating properly and that the calibration has not
changed.
b. The same check
standards used in the preparation of the tolerance chart or control chart at
the time of calibration must be used in the calibration verification of the
instrument.
c. The check standards
must provide adequate counting statistics for a relatively short count time.
The sources must be sealed or encapsulated to prevent leakage and contamination
of the instrument and laboratory personnel.
d. For alpha and gamma spectroscopy systems,
the instrument calibration verification must include checks on the counting
efficiency and the relationship between channel number and alpha or gamma ray
energy.
e. For gamma spectroscopy
systems, the calibration verification checks for efficiency and energy must be
performed at least weekly along with performance checks on peak
resolution.
f. For alpha
spectroscopy systems, the calibration verification check for energy must be
performed at least weekly and the performance check for counting efficiency
must be performed at least monthly for each day the instrument is used for
sample analysis.
g. For
gas-proportional and scintillation counters, the calibration verification check
for counting efficiency must be performed each day of use.
10. Background radiation measurement
a. Background radiation measurements must be
performed on a regular basis and monitored using control charts or tolerance
charts to ensure that a laboratory maintains its capability to meet required
data quality objectives.
b.
Background radiation measurement values must be subtracted from the total
measured activity in the determination of the sample activity.
c. For gamma spectroscopy systems, background
radiation measurements must be performed at least monthly.
d. For alpha spectroscopy systems, background
radiation measurements must be performed at least monthly.
e. For gas-proportional counters, background
radiation measurements must be performed at least weekly.
f. For scintillation counters, background
radiation measurements must be performed each day of use.
11. Instrument contamination monitoring
A laboratory must have a written procedure for monitoring radiation measurement instrumentation for radioactive contamination. The procedure must indicate the frequency of the monitoring and must indicate criteria that initiate corrective action.
12. Method detection limits
a. Detection limits must be determined before
sample analysis and must be redetermined each time there is a significant
change in the test method or instrument type.
b. The procedures employed must be documented
and consistent with published references.
13. Quality of standards and reagents
a. The QA manual must describe the
procurement, use and storage of radioisotope standards.
b. Reference standards that are used in a
radiochemical laboratory must be obtained from an accredited third party or a
National Metrology Institute (e.g., NIST) and be traceable to the SI,
International System of Units.
c.
Reference standards must be accompanied with a certificate of calibration that
describes traceability to the SI, International System of Units, from an
accredited third party or a National Metrology Institute (e.g., NIST) when
appropriate.
d. Laboratories must
consult with the supplier if the laboratory's assessment of the activity of the
reference traceable standard indicates a noticeable deviation from the
certified value. The laboratory must not use a value other than the
decay-corrected certified value.
e.
All reagents used must be of analytical reagent grade or better.
Disclaimer: These regulations may not be the most recent version. Maine may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google
Privacy Policy and
Terms of Service apply.
