(a)
General Requirements.
1.
Quality Assurance
Plan. Certified laboratories shall establish, maintain, and follow
a written Quality Assurance (QA) Plan acceptable to the Department. Each
laboratory's QA plan shall be made available to all analysts employed by the
laboratory. At a minimum, QA plans shall include:
a. QA organization and
responsibility;
b. QA objectives
for precision and accuracy;
c.
Standard operating procedures (SOPs) that accurately reflect all phases of
current laboratory activities. The standard operating procedures section of a
laboratory's QA plan shall include the following:
i. Sample receipt and handling procedures
including sample custody and storage procedures;
ii. Calibration procedures and
frequencies;
iii. Analytical
procedures, including any modifications to published procedures;
iv. Data reduction, validation and reporting
procedures;
v. Internal quality
control procedures (type and frequency);
vi. Provision for performance and system
audits, both internal and external, and schedules;
vii. Preventive maintenance procedures and
schedules;
viii. Specific
procedures for assessing data precision and accuracy;
ix. Procedures for taking corrective
actions;
x. Quality assurance
reporting procedures; and
xi.
Laboratory safety plans.
A standard operating procedure for an analytical method or
other laboratory procedure may be a separate document. The QA plan must include
a list of all such standard operating procedures. Only the laboratory director
or supervisor may make changes in standard operating procedures. Such changes
shall be effective only when put in writing.
d.
Record
Maintenance. The record maintenance procedures section of a
laboratory's QA plan shall include the procedures for creating, controlling,
and maintaining the following records:
i. Raw
data (including, but not limited to, laboratory notebooks, instrument
printouts, and electronic records);
ii. Chain-of-custody records;
iii. Calculations;
iv. Quality control data; and
v. Reports.
2.
Temperature
Records.
a. A laboratory shall
measure and record the temperature of each drying oven and hot-air sterilizing
oven for each day of use. The temperature measurement device must be immersed
in sand or other suitable material and placed on one of the shelves. A
laboratory may use a temperature-measuring device that can be read from outside
the oven without the need to open the door provided that it has verified the
accuracy of the device.
b. A
laboratory shall measure and record the temperature of each refrigerator and
incubator either continuously or each day of use. The thermometers must be
immersed in liquid and placed on one of the shelves. A laboratory may use a
temperature-measuring device that can be read from outside the refrigerator or
incubator without the need to open the door provided that it has verified the
accuracy of the device.
3.
Laboratory Chemicals and
Reagents. Analytical reagent (AR) grade or American Chemical
Society (ACS) grade chemicals or better are required for analyses, unless
otherwise required by the analytical method. In addition, laboratory chemicals
and reagents shall meet the following requirements:
a. All chemicals shall be labeled with the
date of receipt by the laboratory to prevent the use of outdated
reagents;
b. Stock and working
standard solutions shall be compared with check standards and inspected prior
to use for signs of decomposition, such as formation of precipitates,
evaporation, and/or discoloration;
c. All reagents and standards shall be
labeled with identification of the compound, concentration, solvent, date of
preparation, date of expiration, and the name of the analyst who prepared the
solution;
d. Preparation of all
stock standards and primary dilution standards shall be documented, and the
concentration of stock and working calibration standards shall be verified
against a primary dilution standard prepared from a source of reagents
different from those used to prepare the calibration standards; and
e. The use of the acceptable grade of
reagents and compressed gases required by the analytical procedure employed
shall be documented.
4.
Laboratory Glassware. The laboratory must follow
cleaning procedures for glassware and other labware that are specified in the
analytical methods. If no specifications are given in a method, then glassware
and sample containers must be cleaned prior to use by washing in a warm
detergent solution, followed by thorough rinsing with tap water and several
additional rinses using deionized or distilled water. The laboratory must use a
detergent designed for laboratory use. Commercially prepared glassware and
sample containers may be used provided the laboratory documents the source and
cleaning procedures utilized. Certain analytical methods may require additional
glassware preparation procedures or the maintenance of a separate dedicated set
of glassware.
5.
Maintenance of Laboratory Instrumentation and
Equipment. Analytical instrumentation and equipment shall be
maintained in accordance with the manufacturer's instructions, analytical
method requirements, and good laboratory practices. A secure record of
maintenance procedures shall be maintained for each instrument and piece of
equipment.
6.
Instrumentation Calibration Requirements.
a.
General
Requirements.
i. Unless directed
otherwise by the analytical method employed, all instruments shall be
calibrated immediately prior to analysis using a minimum of a blank and three
calibration standards that bracket the expected concentration range,
ii. Unless directed otherwise by the
analytical method employed, all instrument calibrations shall be verified
through the analysis of a calibration check sample that has been prepared using
a source of reagents different from that used to prepare the calibration
standards. Unless directed otherwise by the analytical method employed, the
calibration check sample shall be analyzed at the beginning and at the
conclusion of the analysis session and after every 20 or fewer samples. If the
result does not agree within 20% of the original value, corrective action shall
be taken.
iii. For instruments with
a calibration curve that has been set by the instrument manufacturer, the
laboratory shall verify the calibration curve using a minimum of three
calibration check standards that bracket the expected concentration range. The
check standards shall represent low, medium, and high concentrations and
include a standard at the minimum reporting level (MRL). If the result of the
calibration check does not agree within 10% of the assigned value of each check
standard, instrument recalibration must be performed.
iv. The laboratory shall keep a secure record
of instrument calibration procedures.
b.
Analytical
Balance. Each analytical balance shall be checked and adjusted
annually by a qualified service person. The accuracy of each analytical balance
shall be checked each day it is to be used using a minimum of two ASTM Class 1
weights, or equivalent, in ranges appropriate to the laboratory's weighing
needs. The laboratory shall keep a secure record of the results of accuracy
checks, the date performed, and the signature of the analyst who performed the
check. The non-reference weights used for this check must be calibrated
annually using reference weights and the results recorded. The accuracy of
reference weights must be certified every five years. The balance level shall
be checked prior to each use and adjusted if necessary.
c.
pH Meters. Each
pH meter shall be calibrated daily or prior to each use with pH 7.0 and pH 4.0
or 10.0 buffer standards that bracket the expected value of the sample, medium,
or reagent being tested. The buffers used shall be recorded, including the date
of calibration and the name of the analyst who performed the calibration.
i. The laboratory must use pH buffer aliquots
only once.
ii. The laboratory must
date commercial buffer solution containers upon receipt and when opened.
iii. The laboratory must record
the pH meter slope monthly after calibration and take corrective action if the
slope falls outside the range of 95% to 105%.
d.
Conductivity
Meters.
i. The conductivity
meter must be calibrated at least monthly using a certified and traceable
low-level standard. Alternatively, the laboratory must determine the cell
constant monthly.
ii. An in-line
meter may be used to check reagent-grade water provided that it is calibrated
annually.
e.
Thermometers. The accuracy of all temperature
measurement devices used to monitor temperatures shall be verified by comparing
the reading of each device with that of a certified reference thermometer that
is graduated in degree increments no larger than those of the device whose
accuracy is being verified. The laboratory must discontinue use of a
thermometer graduated in 0.5°C increments or less that differs from the
certified thermometer by more than 1°C. The accuracy of glass and
electronic thermometers must be verified annually; metal thermometers must be
verified quarterly; infrared detection devices must be verified every six
months; and the certified reference thermometer must be calibrated at least
once every five years. The correction factor and date of verification of
accuracy must be indicated on the thermometers. The laboratory shall maintain a
secure record that includes:
i. The
identification number of each thermometer;
ii. The temperatures displayed on both the
certified thermometer and the thermometer being verified;
iii. Any applicable correction
factor;
iv. The date each check was
performed; and
v. The signature of
the analyst who performed each check.
f.
On-line Monitors and Portable
Equipment. Continuous on-line monitors and portable equipment used
in obtaining on-site measurements must be calibrated in accordance with the
manufacturer's instructions. The calibration must be verified through analysis
of an independent check sample or use of an independent monitoring technique.
Verification shall be recorded.
g.
Spectrophotometer Wavelength Verification. The
wavelength setting of the spectrophotometer shall be checked annually by
comparing the wavelength setting to that of colored standards or filters, such
as didymium glass. The wavelength observed, date of performance, and the name
of the analyst or service person that performed the check shall be
recorded.
h.
Top-loader
Balance. Each top-loader balance must be checked for accuracy
monthly in its range of use with ASTM Class 1 weights or equivalent.
7.
Sample
Collection, Preservation and Handling.
a. Acceptable procedures, as referenced or
defined in current federal regulations shall be utilized for sample collection,
handling and preservation.
b. The
laboratory may reject the sample if it is not assured of the sample
identification or of the validity of the sample collection, handling and
preservation procedures. The laboratory must have a written policy listing its
criteria for rejection of samples. When rejecting a specific sample, the
laboratory must document the reason(s) for the rejection.
c. Samples shall be stored in such a way that
cross-contamination from other samples, standards or reagents is
avoided.
d. The laboratory shall
adhere to the sample and extract holding times prescribed in the analytical
methods.
e. Chain-of-custody
information must include:
i. Sample
number;
ii. Sample description
including any preservation (e.g., chemical, thermal,
etc.) used;
iii.
Date and time of sample collection;
iv. Specific location of sample
collection;
v. Name of sample
collector and intermediate custodians, if any;
vi. Date(s) and time(s) of custody transfer
to the laboratory; and
vii. Name(s)
and signature(s) of the individual(s) receiving the sample.
f. A chain-of-custody form must
accompany all samples including those shipped by mail or courier.
g. The laboratory shall maintain a system of
internal sample tracking that documents sample custody from the time of receipt
at the laboratory to the time of disposal.
8.
Analytical
Methodology. The laboratory shall utilize acceptable analytical
methods. The acceptable methods shall be those defined or referenced in 40 CFR
parts 136, 141 and 143, and
310 CMR
22.00: Drinking Water, for the
environmental matrix being tested.
(b)
Additional Requirements for
Chemical and Radiochemical Laboratories.
1.
Quality Control
Procedures.
a. Unless directed
otherwise by the analytical method or the Department standard employed, the
laboratory shall prepare and analyze a laboratory reagent blank, sample
duplicate, and laboratory fortified blank for every 20 or fewer samples
processed as an analytical batch. Duplicates of radiochemical samples must be
prepared and analyzed for every ten or fewer samples. In addition, a laboratory
fortified sample matrix shall be run if required by the Department. Corrective
action shall be taken if the results of these analyses do not meet acceptance
criteria developed within the laboratory according to accepted analytical
procedures. The preparation of blanks, laboratory fortified sample matrices,
and duplicates and the results of their analyses shall be recorded.
b. Each laboratory must establish acceptance
limits for precision and accuracy and maintain and use quality control charts
for each of the analytes in the matrices, disciplines, and categories in which
the laboratory is certified. These limits may not be less stringent than those
defined in approved analytical methods or approved by the Department.
c. Certified laboratories shall utilize
surrogate analytes as required by the analytical procedure employed. Acceptance
limits for surrogate analyte recoveries shall be established by the laboratory.
Quality control charts must be maintained and used for each
surrogate.
d. Certified
laboratories shall perform and document all quality control procedures in
established analytical protocols or the quality control procedures the
Department requires and specifies.
e. When integrating chromatography peaks,
either automatically or manually, each laboratory must ensure that integrations
are performed in a correct and consistent manner for standards and samples,
including quality control samples. Each laboratory must maintain documentation
of manual integrations that includes the following:
i. The laboratory's written procedure for
manual integration;
ii. The
original chromatogram and the manually integrated chromatogram; and
iii. The analyst's initials, date of manual
integration, and the reason(s) for the manual integration.
2.
Determination of
Method Detection Limit.
a. Each
laboratory shall experimentally determine the method detection limit for
analysis of each analyte, except pH, for each matrix in which the laboratory is
certified.
b. The laboratory must
document its procedure for determining the method detection limit. The
laboratory must use the procedure for determining the method detection limit
that is described in the analytical method being used. If the analytical method
does not include a procedure for the determination of method detection limits,
then the laboratory must determine the method detection limit using the
procedure described in 40 CFR Part 136: Appendix B or other
Department- or EPA-approved procedure. For those analytes requiring pattern
recognition for identification (e.g., chlordane, toxaphene),
the method detection limit is defined as the lowest concentration at which
pattern recognition is possible.
c.
Calculations and supporting documentation used in determining limits must be
available for inspection.
d.
Detection limits shall be expressed in appropriate units.
e. The laboratory must achieve the method
detection limits required by the applicable regulations.
f. Sample preparation and analyses for the
method detection limit calculation must be made over a period of at least three
days.
g. Method detection limits
must be determined as part of a laboratory's initial demonstration of
capability to perform an analysis, when any change occurs in the laboratory
that could affect the method detection limits, and as required by an analytical
method.
h. Method detection limits
must be determined using analysts and instruments that are representative of
those used in the performance of analyses,
i. The laboratory must verify its capability
to analyze low level samples on an ongoing basis through the analysis of low
level standards or through a method detection limit determination.
j. The laboratory shall determine the minimum
reporting level for analysis of each analyte, except pH, for each matrix in
which the laboratory is certified. The laboratory shall document the procedure
used to determine the minimum reporting level. The laboratory shall verify the
minimum reporting level on an ongoing basis.
3.
Laboratory Reagent
Water. The laboratory must demonstrate that its reagent water
meets the specifications required by the analytical methods it uses including
that it is free of analytes of interest above their method detection limits.
When the method specifies the resistance or conductivity of the source of
reagent water, verification of such quality shall be made and documented each
day the water is used.
(c)
Additional Requirements for
Microbiology Laboratories.
1.
Autoclaves.
a. For
each sterilization cycle, the signature of the analyst, date, sterilization
time and temperature, the materials being autoclaved and their total time in
the autoclave shall be recorded.
b.
A maximum-temperature-registering thermometer, electronic temperature readout
device, or continuous recording device must be used during each autoclave
cycle. The temperature must be recorded.
c. Automatic timing mechanisms must be
checked quarterly with an accurate timepiece, such as a stopwatch, and the
results recorded.
d. The laboratory
must check the performance of the autoclave each week during which the
autoclave is used with Geobacillus stearothermophilus spore
strips, suspensions, or capsules and record the results.
e. Biological waste must be autoclaved for at
least 30 minutes followed by proper disposal.
2.
Hot Air Sterilizing
Ovens. The laboratory must check the performance of the hot air
sterilizing oven each week during which the oven is used with Bacillus
subtilis or Bacillus atrophaeus spore strips and
record the results.
3.
Incubators.
a.
Incubators, both air-type and water bath, must maintain the temperature
specified by the method. On days when the incubator is in use, the temperature
of each incubator must be recorded continuously or at least twice per day, with
each reading separated by at least four hours and the times of each reading
recorded. For air-type incubators, the thermometer shall be immersed in liquid
and placed on one of the shelves in use.
b. If an aluminum block incubator is used,
culture dishes and tubes must fit snugly.
c. Water bath incubators must be cleaned at
least monthly.
d. The laboratory
must record the date and time at the beginning and at the end of sample
incubation.
4.
Germicidal Ultraviolet Lamps. Germicidal ultraviolet
lamps shall be tested quarterly by exposing agar spread plates containing 200
to 250 microorganisms to the light for two minutes. If such irradiation does
not reduce the count of control plates by 99%, the lamps shall be replaced.
Alternatively, the laboratory shall use an ultraviolet light meter to ensure
that the lamp emits at least 70% of its initial output. Cleaning of germicidal
ultraviolet lamps shall be done at least monthly by disconnecting the unit and
cleaning the lamps with a soft cloth moistened with ethanol.
5.
Microscopes. The
optics and stage of microscopes shall be cleaned with lens paper prior to each
use.
6.
Sterility of
Rinse/Dilution Water and Sample Bottles.
a. Each batch or lot of dilution/rinse water
must be checked for sterility by adding 50 mL of the water to a 50 mL volume of
a double strength non-selective broth (e.g., tryptic soy
broth, trypticase soy broth, or tryptose broth), which is then incubated at
35°C ± 0.5°C and checked for turbidity signifying growth at 24
and 48 hours and the results recorded.
b. After sterilization, at least one bottle
per batch of sterilized sample bottles or per lot of commercially prepared
sample containers shall be checked for sterility by adding approximately 25 mL
of sterile non-selective broth medium to each bottle. The bottle shall be
capped and rotated so that the broth comes in contact with all surfaces and
shall be incubated at 35°C ± 0.5°C and checked for growth at 24
and 48 hours and the results recorded. Prepared sample bottles from each batch
or lot shall not be used unless satisfactory results are obtained from the
tested bottle.
7.
Residue Testing of Glassware.
a.
Inhibitory Residue
Test. With the initial use of each lot of a detergent or washing
product, the rinsing process using distilled or deionized water shall be
demonstrated to provide glassware that is free from toxic material based on the
use of the Inhibitory Residue Test, as specified in the most recent edition of
Standard Methods for the Examination of Water and Wastewater,
American Public Health Association, American Water Works Association,
Water Environment Federation, Washington D.C. The results of the test must be
recorded. Alternatively, the laboratory may obtain written, traceable
certification from the product manufacturer that the inhibitory residue test
has been performed on the lot of detergent or washing product according to the
Standard Methods procedure. The actual test results must be
included with the certification.
b.
Bromthymol Blue Test. Each batch of clean, dry
glassware or plasticware shall be tested for residual alkaline or acid residue
using bromthymol blue indicator and the results recorded. If the results of the
indicator test are not within the desired color range of light green to dark
blue, corrective action shall be taken by re-rinsing, air drying and
retesting.
8.
Microbiological Media - Quality Control Measures.
a. The laboratory shall keep records that
indicate the kind, amount, date received, lot number, expiration date, and date
of opening of bottles of media. Media shall be stored in a desiccator or cool,
dry location. If caking or discoloration of media occurs, media shall be
discarded.
b. Records shall be
available for inspection on all batches of laboratory-prepared media showing
lot numbers, date prepared, details of preparation, total volume prepared,
sterilization time and temperatures, final pH, and the name of the individual
who performed the work.
c. Prior to
first use of media, the laboratory shall test each batch of medium prepared in
the laboratory and each lot of pre-prepared, ready-to-use medium with at least
one pure culture of a known positive reaction.
d. Prior to first use of media, the
laboratory shall test each batch of medium prepared in the laboratory and each
lot of pre-prepared, ready-to-use medium with one or more negative culture
controls, i.e., non-target organisms, as appropriate to the
method.
e. Prepared plates shall be
refrigerated in sealed containers with a label containing the date of
preparation or expiration and the name of the medium. Plates may be kept no
more than two weeks following preparation. Broth media in loose-capped test
tubes may be kept no more than two weeks following preparation. Broth media in
tightly capped tubes may be kept three months from the date of
preparation.
9.
Dechlorination Sufficiency. If chlorinated water is to
be analyzed, sufficient sodium thiosulfate must be added to the sample bottle
before sterilization to neutralize any residual chlorine in the water sample.
The laboratory may also use commercially prepared, pre-sterilized bags or
bottles containing sodium thiosulfate.
10.
Membrane Filter Procedure
Quality Control Specifics.
a.
Only membrane filters recommended for water analysis by the manufacturer shall
be used.
b. Lot numbers of membrane
filters and date of receipt shall be recorded.
c.
Procedural
Contamination. A start and finish membrane filtration control test
of rinse water, medium, and supplies shall be conducted for each filtration
series. If sterile controls indicate contamination, all data on samples
affected shall be rejected and a request made for immediate resampling of those
waters affected.
d.
Verification of Membrane Filter Colonies on m-Endo
medium.
Total Coliform Procedure. All sheen or
borderline colonies up to ten on each membrane shall be verified in accordance
with the accepted standard procedure contained in the latest edition of
Standard Methods for the Examination of Water and Wastewater (Standard
Methods).
11.
Quality Control.
a. When quality control samples are
available, each analyst shall analyze at least one quality control sample per
year for the categories to be certified.
b. During the initial training of an analyst
in a method requiring the identification and enumeration of colonies, the new
analyst must count plates from at least ten positive samples having varying
colony counts within the ideal counting range for the method. The laboratory
supervisor must count the same plates. The replicate counts between the
analysts must agree within 10%.
c.
For methods used for the enumeration of colonies, 10% of routine samples must
be analyzed in duplicate and the range of logs determined. Corrective action
shall be taken if the results of these analyses do not meet acceptance criteria
developed within the laboratory according to accepted analytical
procedures.
12.
Laboratory Reagent Water. The laboratory shall use
satisfactorily tested reagent water from a water purification system
(e.g., still, deionization unit, or a reverse-osmosis unit) to
prepare media, reagents, and dilution/rinse water for performing microbial
analyses.
a. If the source water is
chlorinated, the laboratory reagent water must be tested monthly for total
chlorine residual and found to contain less than 0.1 mg/L of chlorine
residual.
b. The laboratory reagent
water must be analyzed annually for the presence of lead, cadmium, chromium,
copper, nickel, and zinc. The concentration of each metal must be no greater
than 0.05 mg/L. The concentration of the metals collectively must be no greater
than 0.1 mg/L.
c. The conductivity
of the laboratory reagent water must be monitored each day that the water is
used and found to be less than 2 µS/cm at 25°C or greater than 0.5
megohms-cm resistance at 25°C.
d. A heterotrophic plate count must be
performed on the laboratory reagent water monthly. The laboratory may use the
reagent water only if the heterotrophic plate count is less than 500
CFU/mL.
e. The test of the
bacteriological quality of the laboratory reagent water must be performed
annually. The ratio of the growth rate must be between 0.8 and 3.0. The test is
described in Section 9020B of the 18th and
19th editions of Standard Methods for the
Examination of Water and Wastewater. The bacteriological quality test
is not required of laboratories that document that their laboratory reagent
water meets the criteria for Type II water or better, as defined in
Standard Methods (18th and
19th editions), Section 1080C or Medium quality
water or better as defined in Standard Methods
(20th edition), Section 1080C.