United States
Environmental Protection
Agency •
Office of Water
Engineering and Analysis Division (43O3) December 1996
Washington, DC 20460
SEPA Methods for Organic Chemical
Analysis of Municipal and industrial
Wastewater
52-001-1-
Printed on Recycled Pap
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Methods for Organic Chemical Analysis
of Municipal and Industrial Wastewater
Prepared by
Analytical Methods Staff
Engineering and Analysis Division (4303)
Office of Science and Technology
Office of Water
U. S. Environmental Protection Agency
Washington, DC
December 1996
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Foreword
Ibis document contains a compilation of the test procedures approved for the analysis of
municipal and industrial wastewater under the Clean Water Act and listed at Appendix A to 40 CFR part
136. The compilation includes EPA 600- and 1600- series methods for the analysis of organic compounds.
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Environmental Protection Agency
Pt. 136, App. A, Moth. 601
form any analysis necessary to deter-
mine whether the alternate method
satisfies the applicable requirements of
this parti; and the Director of EMSL-CI
shall recommend to the Administrator
that he/she approve or reject the appli-
cation and shall also notify the appli-
cant of such recommendation.
(3) As expeditiouBly as practicable,
an alternate method determined by the
Administrator to satisfy the applicable
requirements of this part shall be pro-
posed by EPA for incorporation in sub-
section 136.3 of 40 CFR part 136. EPA
shall make available for review all the
factual bases for its proposal, including
any performance data submitted by the
applicant and any available EPA anal-
ysis of those data.
(4) Following: a period of public com-
ment. EPA shall, as expedittpusly as
practicable, publish in the FEDERAL
REGISTER a final decision to approve or
reject the alternate method.
[38 FR 28760. Oct. 16. 1913. as amended at 41
PR 52785. Dec. 1. 1976; 55 FR 33440. Aug. 15.
1990]
APPENDIX A TO PART 136—METHODS FOR
ORGANIC CHEMICAL ANALYSIS OF
MUNICIPAL AND INDUSTRIAL
WASTEWATER
METHOD 601—PDBOBABLB HALOCABBONS
1. Scope and Application
1.1 This method coven the determination
of29purgeablehalocarbons. .
The following parameters may be deter-
mined by this method:
rifchto
CMoroetham
ChtoftrfofRi •
CMOfOflMttllM '.
pfcfonxKShtaroflM'thftnft
1.2-Ok
1.3
1,4-Ofchtorotoenzane
DfchtorodMu
Bthara
1.1-OicMoRMthane
I.HJichtororttwne
trara-1 ^Oiehtoroethane
d»-1,3-0ichloropcop.
trara-l^Oichla
STORET
No.
32101
32104
34413
32102
34301
34311
34576
32106
34418
34586
34571
4JMKI
wWHJD
34496
34531
34501
34546
34541
34704
34899
34423
CAS No.
75-27-4
75-25-2
74-83-9
58-23-5
108-90-7
75-00-3
100-75-8
67-66-3
74-87-3
95-60-1
541-73-1
106^46-7
75-71-8
75-34-3
107-06-2
75-35-4
158-60-6
78-87-5
10061-01-6
10061-02-8
75-09-2
•PM*
1,1.22-TtfrHMaroadMM .
vinyl eMnrkft ' < .
tilUHbl'
No.
34516
34475
34508
34511
38180
344S3
39715
CAS No.
79-34=5
127-18-4
71-66-8
79-00-5
79-01-4
75-80-4
75-01-4
1.2 This is a purge and trap gas chroma-
tographic (GC) method applicable to the de-
termination of the compounds listed above
In municipal and industrial discharges as
provided under 40 CFR 136.1. When this meth-
od is used to analyze linfttrqWM' samples for
'any or all of the compounds above.
compound identifications should be sup-
ported by at least one additional qualitative
technique. This method describes analytical
conditions for a second gas chromatographic
column that can be used to confirm measure-
ments made with the primary column. Meth-
od 624 provides gas chromatograph/mass
spectrometer (OC/MS) conditions appro-
priate for the qualitative and quantitative
confirmation of results for most of the pa-
rameters listed above.
14 The method detection limit (MDL. de-
fined in Section 12.1)« for each parameter is
listed in Table 1. The MDL for & specific
wastewater may differ from those listed, de-
pending upon the nature of interferences in
the sample matrix.
1.4 Any modification of this method, be-
yond those expressly permitted, shall be con-
sidered as a major modification subject to
application and approval of alternate test
procedures under 40 CFR 138.4 and 138.5.
1.5 This method is restricted to use by or
under the supervision of analysts experi-
enced in the operation of a purge and trap
system and a gas chromatogFaph and in the
interpretation of gas chromatograms. Each
analyst must demonstrate the ability to gen-
erate acceptable results with this method
using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL
water sample contained in a specially-de-
signed purging chamber at ambient tempera-
ture. The halocarbons are efficiently trans-
ferred from the aqueous phase to the vapor
phase. The vapor is swept through a sorbent
trap where the halocarbons are trapped.
After purging is completed, the trap is heat-
ed and backflnshed with the inert gas to
desorb the halbcarbons onto a gas
chromatographic column. The gas chro-
matograph is temperature programmed to
separate the halocarbons which are then de-
tected with a hallde-specific detector.*-3
2.2 The method provides an optional gas
chromatographic column that may be help-
ful in resolving the compounds of interest
from interferences that may occur.
647
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W..136, App. A, M«itl. 601
* •
••3. Interferences
3.1 Imparities in the purge gas and or-
ganic compounds outgassing from the plumb-
• ing ahead of the trap account for the major-
ity of contamination problems. The analyt-
ical system must be' demonstrated to be free
from contamination under the conditions of
the analysis by running laboratory reagent
blanks as described in Section 8.13. The use
of non-Tenon plastic tubing. non-Tenon
thread sealants, or now controllers withrub-
ber components in the purge and trap system
should be avoided, •
3£ Samples can be contaminated by diffu-
sion of volatile organics (particularly nuoro-
oarbons and methylene chloride) through the
septum seal ilto the sample during shipment
and storage. A field reagent blank prepared
from reagent water and carried through the
sampling and handling protocol can serve as
a check on such contamination.
33 Contamination by carry-over can
oocur whenever high level and low level sam-
ple* are sequentially analysed. To reduce
carry-over, the purging device and sample
syringe must be rinsed with reagent water
between sample analyses. Whenever an un-
usually concentrated sample is encountered.
it should be followed by an analysis of rea-
gent water to check for cross contamination.
For samples containing large amounts of
water-soluble materials, suspended solids.
high boiling compounds or high organohalide
levels, it may be necessary to wash out the
purging device with a detergent solution,
rinse it with distilled water, and then dry it
in a 105*O oven between analyses. The trap
and other parts of the system are also sub-
•jftot to contamination; therefore, frequent
bakeout and purging of the entire system
may be required. ' .
4:Safetu
4.1 The toxicity or cardnogenlcity of
each reagent used in this method has not
been precisely defined; however, each chemi-
cal compound should be treated as a poten-
tial health haxard. From this viewpoint, ex-
posure to these chemicals must be reduced to
the lowest possible level by whatever means
available. The laboratory is responsible for
- - - a current awareness file of
. ,
OSHA regulations regarding the safe han
dling of the ohftml
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Envifonmontat Protection Aojoncy
carder. A data system is rTtfmmmf"**'* tar
measuring peak areas.
5.3.1 Column 1—8 ft Icmg x OJL in. ID stain-
less steel or glass, packed with 1% 8P-1000
on Carbopaok B (60/80 mesh) or equivalent.
This column was used to develop the method
performance statements in Section 12.
Guidelines for the use of alternate column
packings are provided in Section 10.L
5.3.2 Column 2—« ft long x 0.1 in. ID stain-
less steel or glass, packed with chemically
bonded n-octane on Porasil-C (100/120 mesh)
or equivalent.
6&3 Detector—Electrolytic conductivity
or microeoulometric detector. These types Of
detectors have proven effective in the analy-
sis of wastewaters for the parameters listed
in the scope (Section 1.1). The electrolytic
conductivity detector was used to develop
the method performance statements in Sec-
tion 12. Guidelines for the use of alternate
detectors are provided in Section UU.
5.4 Syringes—6-mL glass hypodermic with
Luerlok tip (two each), if applicable to the
purging device.
5.6 Micro syringes—25-)iL. 0.006 in, ID nee-
dle.
5.6 Syringe valve—2-way. with Luer ends
(three each).
5.7 Syringe—6-mL, gas-tight with shut-off
valve.
54 Bottle—15-mL, screw-cap, with Teflon
cap liner.
5J Balance—Analytical, capable of accu-
rately weighing 0.0001 g..
6. Reagents
6.1 Reagent water—Reagent water is de-
fined as a water in which an interferent is
not observed at the MDL of the parameters
of interest.
6.1.1 Reagent water can be generated by
imitirtng tap water through a carbon filter bed
containing about 1 Ib of activated carbon
(Flltrasorb-aoo. Calgon Corp.. or equivalent).
6.1.2 A water purification system
(Mlllipore Snper-Q or equivalent) may be
used to generate reagent water.
6.1.3 Reagent water may also be prepared
by boiling water for 15 min. Subsequently.
while maintaining the temperature at 90 *C,
bubble a contaminant-free inert gas through
the water for 1 h. While still hot. transfer
the water to a narrow month screw-cap bot-
tle and seal with a Teflon-lined septum and
cap.
&2 Sodium thloBulfate—(ACS) Orannlar.
6.3 Trap Materials:
6.3.1 Coconut charcoal—6/10 mesh sieved
to 26 mesh, Barnabey Cheney. CA-590-26 lot #
M-2649 or equivalent.
6.3.2 2.6-Diphenylene oxide polymer—
Tenax, (60/80 mesh), chromatographic grade
or equivalent.
6.35 Methyl silicone packing—8% OV-1 on
Chromosorb-W (60/80 mesh) or equivalent.
Pt. 13A. App. A, Moth. 601
6.3.4 Silica gel-=35/30 mesh; Dayison.
grade-15 or equivalent.
6.4 Methanol—Pesticide quality or equiv-
alent. , .
6.5 Stock standard solutions—Stock
standard solutions may be prepared from
pure standard m*«»rt>iM or purchased as cer-
tified solutions. Prepare stock standard solu-
tions in methanol using assayed liquids or
gases as appropriate. Because of the toxidty
of some of the brganohalides, primary dilu-
tions of these materials should be prepared
in a hood. A NIOSE/MESA approved toxic
gas respirator should be used when the ana-
lyst handles high concentrations of such ma-
terials.
6.5.1 Place about 9.8 mL of met&anol into
a 10-mL ground glass stoppered volumetric
flask. Allow the flask to stand, uhstoppsfad,
for about 10 min or until all alcohol wetted
surfaces have dried. Weigh the flask to the
Iearest0.1mg. . ,
6J^2 Add the assayed reference material:
6.5.2.1 Liquid—Data? a 100 |iL syringe. Im-
mediately add two or more drops of assayed
reference material to the flask, then re-
weigh. Be sure that the drops fall directly
into the alcohol without contacting the neck
of the flask.
6.5^2 Oases—To prepare standards for
any of the six halocarbons that boil below
30* C (bromometfaaae, cbloroethftse. chloro-
methane, dicMorodifluoromethame.
trichloroflnoromethaae, vinyl chloride). Oil
a 5-mL valved gas-tight syringe with the ref-
erence standard to the 5.0-mL mark. Lower
the needle to 5 mm above the methanol me-
niscus. Slowly introduce the reference stand-
ard above the surface of the liquid (the heavy
gas will rapidly dissolve into the methanol).
6££ Reweigh, dilute to volume, stopper.
then T"«» by inverting the flask several
times. Calculate the concentration in |ig/|iL
from the net gain in weight. When compound
purity is assayed to be 98% or greater, the
weight can be used without correction to cal-
culate the concentration of the stock stand-
ard. Commercially prepared stock standards
cftT» be used at any concentration if they are
certified by the malufecturer or by an inde-
pendent source. •• ' "
&S.4 Transfer the stock standard solution
into a Teflon-sealed screw-cap bottle. Store,
with T"^"*I headspaee, at -10 to -20 *C
and protect from light.
6.5£ Prepare fresh standards weekly for
the six gases and 2-chloroethylvlnyl ether.
All other standards must be replaced after
one month, or sooner if comparison with
check standards indicates a problem.
6.6 Secondary dilution standards—Using
stock standard solutions, prepare secondary
dilution standards in methanol that contain
the compounds of interest, either singly or
mixed together. The secondary dilution
standards should be prepared at concentra-
tions such that the aqueous calibration
649
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rt* »«x»,
standards prepared In Section 7.3.1 or 7.4.1
will bracket the working range of the ana-
lytic*! system. Secondary dilation standards
should be stored with T»<«1in^-l headapace and
should be checked frequently for signs of
degradation or evaporation, especially just
• prior to preparing calibration standards from
them.
6.7 Quality control check sample con-
centrate—See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that
meets the specifications in Section 5.2. Con-
dition the trap overnight at 180 *C by
backflnshlng with an inert gas flow of at
least 20 *r>Tifrn1lTir Condition the trap for 10
min onoe daily prior to use.
7.2 Connect the purge and trap system to
a gas chromatograph. The gas chro-
matograph must be operated using tempera-
tare and flow rate conditions equivalent to
thoee given in Table 1. Calibrate the purge
and trap-gas chromatographlc system using
either the external standard technique (Sec-
tion US) or the internal standard technique
(Section 7.4).
7.3- External standard calibration proce-
dure:
7.3.1 Prepare calibration standards at a
tniminnm of three concentration levels for'
each parameter by carefully adding 20.0 |iL of
one or more secondary dilution standards to
100. £00. or 1000 |iL of reagent water. A 25-nL
syringe with a 0.006- in. ID needle should be
used for this operation. One of the external
standards should be at a concentration near.
but above, the HDL (Table 1) and the other
•concentrations should correspond to the ex-
pected range of concentrations found in real
samples or should define the working range '
of the detector. These aqueous standards can
be stored up to 24 h. If held In sealed vials
with zero headspace as described in Section
9.2. If not so stored, they must be discarded
after ih.
7.3.2 Analyze each calibration standard
according, to Section 10. and tabulate peak
height or area responses versus the con-
centration in the standard. The. results can
be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of
response to concentration (calibration fac-
tor) is a constant over the working range
(<10% relative standard deviation. USD), lin-
earity through the origin can be assumed
and the average ratio or calibration factor
can be used in place of a calibration curve.
7.4 Internal standard calibration proce-
dure—To use this approach, the analyst must
select one or more internal standards that
are similar in analytical behavior to the
compounds of interest. The analyst must fur-
ther demonstrate that the measurement of
the internal standard is not affected by
method or matrix interferences. Because of
these limitations, no internal standard can
be suggested that is applicable to all sam-
ples. The compounds recommended for use as
surrogate spikes in Section 8.7 have been
used successfully as internal standards, be-
cause of their generally unique retention
times.
7.4.1 Prepare calibration standards at a
minimum of three concentration levels for
each parameter of Interest as described In
Section 7.3.1:
7.4.2 Prepare a spiking solution contain-
ing each of the Internal standards using the
procedures described In Sections 6.5 and 6.6.
It is recommended that the secondary dilur
tion standard be prepared at a concentration
of 15 \iglmL of each Internal standard
compound. The addition of 10 |iL of this
standard to 5.0 mL of sample or calibration
standard would be equivalent to 30 jig/L.
7.4.3 Analyze each calibration standard
according to Section 10. adding 10 |iL of in-
ternal standard spiking solution directly to
the syringe (Section 10.4). Tabulate peak
height or area responses against concentra-
tion for each compound and Internal stand-
ard. and calculate response factors (RF) for
each compound using Equation 1.
(A.XC*)
RF= — — — —
(AuKC.)
Equation 1
where:
A.=Reaponse for the parameter to be meas-
ured.
for the internal standard.
Ci.=Concentration of the internal standard.
. -C,=Concentration of 'the parameter to be
measured.
If the RF value over the working range is. a
constant (<10%'BSD). the RF can be assumed
to be invariant and the average RF can be
used for calculations. Alternatively, the re-
sults can be used to plot a calibration curve
of response ratios, AJAi.. vs. RF.
7.5 The working calibration curve, cali-
bration factor, or RF must be verified on
each. working day by the measurement of a
QC check sample.
7.5.1 Prepare the QC check sample as de-
scribed in Section B.2J2.
7.5.2 Analyze the QC check sample accord-
ing to Section 10.
7.5.3 For each parameter, compare the re-
sponse (Q) with the corresponding calibra-
tion acceptance .criteria found in Table 2. If
the responses for all parameters of Interest
fall within the designated ranges, analysis of
actual samples can begin, If any individual Q
falls outside the range, proceed according to
Section 7.5.4.
NOTE: The large number of parameters in
Table 2 present a substantial probability
that one or more will not meet the calibra-
tion acceptance criteria when all parameters
are analyzed.
650
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Environmental Protection Agency
7.5.4 Repeat the test only for those pa-
rameters that failed to meet the calibration •
acceptance criteria. If the response for a par
rameter does not' fall within the range in
this second test, a new calibration curve.
calibration factor, or RF must be prepared
for that parameter according* to Section 7.3
or 7.4. .
t. Quality Control
8.1 Bach laboratory that uses this method
is required to operate a formal quality con-
trol in*"K'*™- The »»ntritmm> requirements of
this program consist of an initial demonstra-
tion of laboratory capability and an ongoing
analysis of spiked samples to evaluate and
document data quality. The laboratory must
i records to document the quality, of
Pt. 1*6, App. A» Mefti. dOI
data that is generated. Ongoing data quality
checks are compared, with established per-
formance criteria to determine if the results
of analyses meet the performance character-
istics of the method. When results of sample
spikes Indicate atypical method perform-
ance, a quality control cheek standard must
be analyzed to confirm that the measure-
ments were performed in an In-control mode
of operation.
8.1.1 The analyst must make an initial.
one-time, demonstration 'of the ability to
generate acceptable accuracy and precision
with *h<" method. This ability is established
as described in Section 8.2.
8.1.2 In recognition of advances that are
occurring in chromatography. the analyst is
permitted certain options (detailed in Sec-
tion 10.1) to improve the separations or lower
the cost of measurements. Bach time such a
modification is made to the method, the ana-
lyst is required to repeat the procedure in
Section 8 A. •
8.1.3 Bach day. the analyst must analyse a
reagent water, blank to demonstrate that
Interferences from the analytical system are
under control.
8.1.4 The laboratory must, on an ongoing
basis, spike and analyze a «*»j««<««n«n of 10%
of all samples to monitor and evaluate lab-
oratory data quality. This procedure is. de-
scribed In Section 8.3.
8.1.5 The laboratory must, on an ongoing
basis, demonstrate through the analyses of
quality control check standards that the op-
eration of the measurement system is in con-
trol. This procedure is described in Section
8.4. The frequency of the check standard
analyses is equivalent to 10% of all samples
analyzed but may be reduced if spike recov-
eries from samples (Section 8.3) meet all
specified quality control criteria.
8.1.6 The laboratory must maintain per-
formance records to document the quality of
data that is generated. This procedure is de-
scribed in Section 8.5.
8.2 To establish the ability to generate
acceptable accuracy and precision, the ana-
lyst must perform the following operations.
8.2.1 A quality control (QO check sample
concentrate is required containing each pa-
rameter of interest at a concentration of 10
lig/mL in methanol. The QC check sample
concentrate must be obtained from the U.S.
Environmental Protection Agency. Environ-
mental Monitoring and Support Laboratory
in Cincinnati, Ohio, if available. If not avail-
able from that source, the QC check sample
concentrate must be obtained from another
external source. If not available from either
source above, the QC check sample con-
centrate must be prepared by the laboratory
using stock standards prepared independ-
ently from those used for calibration.
8^2 Prepare a QC check sample to con- •
tain 20 |ig/L of each parameter by adding 209
tiL of QC check sample concentrate to 100 mL
of reagent water.
8.241 Analyze four 5-mL allqnots of the
well-mixed QC check sample according to
flection 10.
8.2.4 Calculate the average recovery (X) in
lig/L, and the standard deviation of the re-
covery (s) in pg/L, for each parameter of in-
terest using the four results.
8££ For each parameter compare s and X
with the corresponding acceptance criteria
for precision and accuracy* respectively.
found in Table 2. If s and X for all param-
eters of interest meet the acceptance cri-
teria, the system performance is acceptable
and analysis of actual samples can begin. If
any individual s exceeds the precision limit
or any Individual X falls outside the range
for accuracy, then the system performance is
unacceptable for that parameter.
None The large number of parameters in
Table 2 present a substantial probability
that one or more will fail at least one of the
acceptance criteria when all parameters are
analyzed.
8.2.6 When one or more of the parameters
tested fall at least one of the acceptance cri-
teria, the analyst must proceed according to
Section 8.2.6.1 or 8^.6.2.
8.2.6.1 Locate and correct the source of
the problem and repeat the test for all pa-
rameters of interest beginning with Section
8A3.
S.2.&2 Beginning with Section 8.2.3, repeat
the test only for those parameters that
failed • to meet criteria. Repeated failure.
however, will confirm a general problem
with the measurement system. If this occurs.
locate and correct the source of the problem
and repeat the test for all compounds of in-
terest beginning with Section 8.2.3.
8.3 The laboratory must, on an ongoing
basis, spike at least 10% of the samples from
each sample site being monitored to assess
accuracy. For laboratories analyzing one to
ten samples per month, at least one spiked
sample per month is required.
8.3.1 The concentration of the spike in the
sample should be determined as follows:
651
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8.3.1.1 If, as in compliance monitoring.
the concentration of a specific parameter in
the sample is being checked against a regu-
latory concentration limit, the spike should
be at that limit or 1 to 5 times higher than
the background concentration determined in
Section &&2, whichever concentration would
be larger.
&3JJI If the concentration of a specific
parameter in the sample is not being
chocked against a limit specific to that pa-
rameter, the spike should be at 20 pg/L or 1
to 6 time* higher than the background con-
centration determined in Section S.&2.
whichever concentration would be larger.
8,3*2 Analyse one 5-mL sample aliquot to ,
determine the background concentration (B)
of each parameter. If necessary, prepare a
new QC check sample concentrate (Section
8&1) appropriate for the background con-
centrations in the sample. Spike a second 5-
mli sample aliquot with 10 pL of the QC
check sample concentrate and analyse it to
determine the concentration after spiking
(A) of each parameter. Calculate each per-
cent recovery .(P) as 100(A-B)%/T, where T is
the* known true value of the spike.
S&3 Compare the percent recovery (P) for
each parameter with the corresponding QC
acceptance criteria found in Table 2. These
acceptance criteria were calculated to in-
clude an allowance for error In measurement
of both the background and spike concentra-
tions, assuming a spike to background ratio
of &l. This error will be accounted for to the
extent* that the analyst's spike to back-
ground ratio approaches 5:1.' If spiking was
performed at a concentration lower than 20
pg/L. the analyst must use either the QC ac-
ceptance criteria in Table 2, or optional QC
acceptance criteria calculated for the spe-
cific spike concentration. To calculate op-
tional acceptance criteria for the recovery of
a parameter: (1) Calculate accuracy (X')
using the equation in Table 3, substituting
the spike concentration (T) for C; (2) cal-
culate overall precision (8') using the equa-
tion in Table 3, substituting Xf for X; (3) cal-
culate the range for recovery at the spike
concentration as (100 X'/D±2.44{100 8VT)%.»
8.3,4 ' If any Individual P falls outside the
designated range for recovery, that param-
eter has failed the acceptance criteria. A
ohi»oV standard containing each parameter
that failed the criteria must be analyzed as
. described in Section 8.4.
8.4 If any parameter fails the acceptance
criteria for recovery in Section 8.3. a QC
check standard containing each parameter
that failed must be prepared and analyzed.
NOTC The frequency for the required anal-
ysis of a QC check standard will depend upon
the number of parameters being simulta-
neously tested, the complexity of the sample
matrix, and the performance of the labora-
tory. If the entire list of parameters in Table
2 must be measured in the sample in Section
8.3. the probability that the analysis of a QC
check standard will be required is high. In
this case the QC check standard should be
routinely analyzed with the spiked sample.
8.4.1 Prepare the QC check standard by
adding 10 pL of QC check sample concentrate
(Section 8.2.1 or 8.3.2) to 5 mL of reagent,
water. The QC check standard needs only to
contain the parameters'that failed criteria
in the test in Section 8.3.
8.4.2 Analyse the QC check standard to
determine the concentration measured (A) of
each parameter. Calculate each percent re-
covery (P.) as 100 (A/T)%. where T is the true
value of the standard concentration.
8.4.3 Compare the percent recovery (P.)
for each parameter with the corresponding
QC acceptance criteria found in Table 2. Only
parameters that failed the test in Section 8.3
need to be compared with these criteria. If
the recovery of any such parameter falls out-
side the designated range, the laboratory
performance for that parameter is Judged to
be but of control, and the problem must be
immediately identified and corrected. The
analytical result for that parameter in the
unspiked sample is suspect and may not be
reported for regulatory compliance purposes.
8.5 As part of the QC program for the lab- ,
oratory, method accuracy for wastewater
samples must be assessed and records must
be maintained. After the analysis of five
spiked wastewater samples as in Section 8JB,
calculate the average percent recovery (P)
and the standard deviation of the percent re-
covery (a,). Express the accuracy assessment
as a percent recovery interval from P-2a, to
P+2v If p*90% and s,dO%. for example, the
accuracy interval is expressed as 70-410%.
Update the accuracy assessment for each pa-
rameter on a regular basis (e.g. after each
five to ten new accuracy measurements).
8.6 It is recommended that the laboratory
adopt additional quality assurance practices
for use with this method. The specific prac-
tices that are most productive depend upon
the needs of .the laboratory and the nature of
the samples. Field duplicates may be ana-
lysed to assess the precision of the environ-
mental measurements. When doubt exists .
over the identification of a peak on the chro-
matogram, confirmatory techniques such as
gas chromatography with a dissimilar col-
umn, specific element detector, or mass
spectrometer must be used. Whenever pos-
sible, the laboratory should analyze standard
reference materials and participate in rel-
evant performance evaluation studies. .
8.7 The analyst should monitor both the
performance of the analytical .system and
the effectiveness of the method in dealing
with each sample matrix by spiking, each
sample, standard, and reagent water blank
with surrogate halocarbons. A combination
of bromochloromethane. 2-bromo-l-
chloropropane, and 1,4-dichlorobutane IB rec-
ommended to encompass the range of the
652
-------
Protection Agoncy
temperature program uaed la this method.
Prom Btook. standard solutions prepared as
in Section 6.5, add a volume to give 760 jig of
each surrogate to 45 mL of reagent water
contained in a 60-mL volumetric flask. mix
and dilate to volume for a concentration of
IS ng/iiL. Add 10 pL of this surrogate spiking
solution directly into the 5-mL syringe with
every sample and reference standard ana-
lyzed. Prepare a fresh surrogate spiking solu-
tion on a weekly basis. If the internal stand-
ard calibration procedure is being used, the
surrogate compounds may be added directly
to the internal standard spiking solution
(Section 7.4.2).
ation.and
9. Sample Collection, Pr
Handling
9.1 All samples must be iced or refrig-
erated from the time of collection until anal-
ysis. If the sample contains free or combined
chlorine, add sodium thiosnlfate lueseiva-
ttve (10 mg/40 mL is sufficient for up to 5
ppm CU) to the empty sample bottle Just
prior to shipping to the «*»»pn«nr site. EPA
Methods 830.4 and 330.5 may be used for
measurement of residual chlorine.* Field test
kits are available for this purpose.
9.2 Grab samples must be collected in
glass containers having a total volume of at
least 25 ml* Pill the sample bottle Just to
overflowing in such a manner that no air
bubbles pass through the sample as the bot-
tle is being filled. Seal the bottle so that no
air bubbles are entrapped in it. If preserva-
tive has been added, shake vigorously for 1
min. MHr**1" the hermetic seal on the sam-
ple bottle nrttM time of analysis.
9.3 All samples must be analysed within
14 days of collection.*
10. Procedure
10.1 Table 1 summarizes the recommended
operating conditions for the gas chro-
matograph. Included in this table are esti-
mated retention times and MDL that can be
achieved under these conditions. An example
of the separations achieved by Column 1 is
shown in Figure 5. Other packed columns.
chromatographic conditions, or detectors
may be used if the requirements .of Section
8.2 are met.
10.2 Calibrate the system daily as de-
scribed in Section 7.
10.3 Adjust the purge gas (nitrogen or he-
lium) flow rate to 40 mLflmin. Attach the
trap inlet to the purging device, and set the
purge and trap system to purge (Figure 3).
Open the syringe valve located on the purg-
ing device sample introduction needle.
10.4 Allow the sample to come to ambient
temperature prior to introducing it to the
syringe. Remove the plunger from a 5-mL sy-
ringe and attach a closed syringe valve. Open
the sample bottle (or standard) and carefully
pour the sample into the syringe barrel to
Pt. 136, App. X McS>- 601
Just short of overflowing. Replace the sy- .
rlnge plunger and cbmprsii the sample. Open
the syringe valve and vent any residual air
while adjusting the sample volume to 5.0 mL.
Since this process of taking? an aliquot de-
stroys the validity of the sample for future
analysis, the analyst should fill a second sy-
ringe at this time to protect against possible
loss of data. Add 10.0 pL of the surrogate
spiking solution (Section 8.7) and 10.0 |iL of
the Internal standard spiking solution (Sec-
tion 7.4.2), if applicable, through the valve
bore, then close the valve.
10.5 Attach the syringe-syringe valve as-
sembly to the syringe valve on the purging
device. Open.the syringe valves and inject
the sample into the purging chamber.
10.6 Cloee both valves and purge the sam-
ple for 'll.0±0.1 min at ambient temperature.
10.7 After the 11-min purge time, attach
the trap to the chromatograph, adjust the
purge and trap system to the desorb mode
(Figure 4), and begin to temperature pro-
gram the gas chromatograph. Introduce the
trapped materials to the QC column by rap-
Idly heating the trap to 180 "C while
baokfliiiiMtig the trap with an inert gas be-
tween 20 and 60 T"T^mi« for 4 min. If rapid
heating of the trap cannot be achieved, the
QC column must be used as a secondary
trap by cooling It to 30 «C (subamblent tern- .
perature. if poor peak geometry or random
retention time problems persist) instead of
the t«««*ai program temperature of 45 *C
10.8 While the trap Is being deeorbed into
the gas chromatograpb, empty the purging
oframvw aging the sample introduction sy-
ringe. Wash the chamber with two 5-mL
flushes of reagent water.
10.9 After desorbing the sample for 4 min.
recondition the trap by returning the purge
and trap system to the purge mode. Walt 15
s then close the syringe valve on the purging
device to begin gas flow through the trap.
The trap temperature should be main-
tained at 180 "C After approximately 7 min.
turn off the trap heater and open the syringe
valve to stop the gas flow through the trap.
When the trap is cool, the next sample can
be analyzed.
1010 Identify the parameters in the sam-
ple by comparing the retention times of the
peaks in the sample chromatogram with
those .of the peaks in standard
chromatograms. The width of the retention
time window used to make identifications
should be based upon measurements of ac-
tual retention time variations of standards
over the course of a day. Three times the
standard deviation of a retention time for a
compound can be used to calculate a sug-
gested window size; however, the experience
of the analyst should weigh heavily in the
Interpretation of chromatograms.
10.11 If the response for a peak exceeds
the working range of the system, prepare a
dilution of the sample with reagent water
653
-------
n. too, App. /s rvivm. ou i
from tlit aliquot in the second syringe and
reanslyse.
XI. CoJculottoTU
, 11.1 Determine the concentration of Indi-
.vidual oompoonds in the sample.
114.1 If the external standard calibration
procedure is used, calculate the concentra-
tion of the parameter being measured from
the peak response using the calibration
curve or calibration factor determined in
Section 7.8A
11.1.2 If the internal standard calibration
procedure is used, calculate the concentra-
tion in the sample using the response factor
(RF) determined in Section 7.4.3 and Equa-
tion 2.
Equation 2
Concentration (iig/L)
where:
A*sRstponse for the parameter to be meas-
ured.
AfcBResponse for the internal standard.
Cfc*Concentration of the internal standard.
11.2 Report results in |ig/L without correc-
tion for recovery data. All QC data obtained
should be reported with the sample results.
12. Method Performance
12.1 The method detection limit (HDL) is
defined as the minimum concentration of a
substance that can be measured and reported
with »% confidence that the value is above
xero.1 The HDL concentration listed in
Table 1 were obtained using reagent water.".
Similar results were achieved using
representative waatewaten. The MDL actu-
ally achieved in a given analysis will vary
depending on instrument sensitivity and ma-
trix effects.
This method is recommended for use
in the concentration range from the MDL to
IQOOxMDL. Direct aqueous injection tech-
niques shotfld be used to measure concentra-
tion levels above lOOQxMDL.
12.3 This method was tested by 20 labora-
tories using reagent water, drinking water.
surface water, and three industrial.
wastewaters spiked at six. concentrations
over the range 8.0 to COO »ig/L.» Single opera-
tor precision, overall precision, and method
accuracy were found to be directly related to
the concentration of the parameter and es-
sentially Independent of the sample matrix.
Linear equations to describe these relation-
ships are. presented in Table 3.
References
1.40 CFR part 136. appendix B.
2. Bellar. T.A.. and Idchtenberg. J.J. "De-
termining Volatile Organlcs at Microgfram-
per-Lltre-Levela by Gas Chromatography."
Journal of the American Water Works Associa-
tion, 66,739 (MM).
3. Bellar. T.A., and Llchtenberg, J.J.
"Semi-Automated Headspace Analysis of
Drinking Waters and Industrial Waters for
Purgeable Volatile Organic Compounds."
Proceedings from Symposium on Measure-
ment of Organic Pollutants in Water and
Waatewater, American Society for Testing
and Materials. STP 686. C.E. Van Hall, edi-
tor, 1978.
4. "Carcinogens—Working With Carcino-
gens," Department of Health, Education, and
Welfare, Public Health Service, Center for
Disease Control. National Institute for Occu-
pational Safety and Health, Publication No.
77-206, August 1077.
5. "OSHA Safety and Health Standards.
General Industry" (29 CFR part 1910). Occu-
pational Safety and Health Administration,
OSHA 2206 (Revised. January 1976).
6. "Safety in Academic Chemistry Labora-
tories." American Chemical Society Publica-
tion. Committee on Chemical Safety, 3rd
Edition. 1979.
7. Provost. L.P.. and Elder, R.8. "interpre-
tation of Percent Recovery Data." American
Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two
times the value 1.22 derived in this report.)
8. "Methods 330.4 (Titrimetric, DPD-PA8)
and 330.5 (Spectrophotometric. DPD) for
Chlorine. Total Residual." Methods for
Chemical Analysis of Water and Wastes, EPA
600/4-79-020, U.S. Environmental Protection
Agency. Environmental Monitoring and Sup-
port Laboratory. Cincinnati. Ohio 45268,
March 1979. ,
9. "EPA Method Study 24. Method 601—
Purgeable Halocarbons by the Purge and
Trap Method." EPA 600/4-84-064. National
Technical Information Service, PB84-212448,
Springfield. Virginia 22161. July 1984.
10. "Method Validation Data for EPA
Method 601," Memorandum from B. Potter,
U.S. Environmental Protection Agency, En-
vironmental Monitoring and Support Lab-
oratory, Cincinnati. Ohio 45268. November 10.
1983.
11. Bellar. T. A.. Unpublished data, U.S.
Environmental Protection Agency. Environ-
mental Monitoring and Support Laboratory.
Cincinnati. Ohio 45268,1981.
654
-------
envtonmontal Protection Agoncy
Pt.
TABLE 1—CHROMATOGRAPWC CONOTTIONS AND METHC» DETECTION Uwns
PuMMOar
etiloroiMtfun*
RMMMon tkiw (nibi)
Cohmnl
140
2.17
242
247
343
7.18
743
940
10.1
10.7
134
13.7
144
162
154
164
164
184
192
214
21.7
242
344
344
364
Column 1 condMont; CarbOMCfc B MO/BO «"••"[«•'•* *g» 1* g'"10"?,?^??
OtMS column «rth h*lum onto gat at 40 mUnto tar rate. Column Mmpmfcn Md
Cchmn2
528
746
nd
528
848
10.1
nd
7.72
124
948
1Z1
164
13.1
144
144
184
184
13.1
164
184
nd
192
nd
154
184
22.4
234
224
048
1.16
141
0.18
042
nd
. 0.13
047
0.10
046
043
0.12
aio
044
044
0.12
049
on?
ais
020
043
043
026
0.16
024
rt 45 *C tor 3 n*i ttwn fto^mm,^a H 8
(W0rt» me*)
umn wHh htfum cwriv got •! 4O
-------
pf. 136, App. A, Moth. 601
40 CFR Ch. I (7-1-95 Edmon)
P.
AS&gft*!
fKovtrf tor tour narMynmm\nmm\\i, jn pyL jSeOJon
raw* Rutte
I.
Nan: These criteria are based directly upon the method performance data In Table 3.
Where necessary. the limits for recovery have been broadened to assure applicability of the
limits to concentrations below those used to develop Table 3.
TABLE 3.— METHOD ACCURACY AND PRECISION AS FUNCTIONS OF CONCENTRATION— METHOD 601
Accuracy. •> r»-
omvy.X'big^)
OWMI praoWan,
rtcNc
096C-2JS
MthVW
0.11X«O04
0.12X40^8
O28X4O27
021X4^41
OJ6X4WJ04
Chtorob
O96C-1.04
1.00C-123
ChQRMlhBM
0.1SX-OQ2
ai4x-ai3
2OtowtiyMny1«(h<
CMorotoiTn _—
ChtoramMhm
QbRMOCMORXMttlM
1J30C
O94C«2.72
O93C*1.70
0.13X40.15
O2BX— (L31
0.11X4-1.10
0.17X«OjB3
O3SX
0.19X-OJB
O24&4.1J6S
0.13X4«.13
1.14**HOR*h«w
I^WcN
1,1*OchlORM«WM
mwl^OfcMo
1^OfcWoroprop«n«'
DfXCfM
taravl^OicMoropropWM*
MWhytamcMockte
1,1A2-T*acrao
T*ncMtttai*m»
1',1,1-TikMoc
1,1^-TrieMor
09SC-000
(L96C-1.M
1.04C-1D6
(Xfiec- OJ7
O07C-0.1B
1.00C
1JOC
1.00C
OB1C-OJ3
096&I0.19
OMC4006
OfiOC-0.16
jBAtQJO
087C4048
aeec-aor
O97C-O36
0.15X44X29
OJKX40.17
0.11X40.70
OJ21X-023
0.11X4-1.46
0.13X
0.18X
0.18X
0.11X40J33
0.14X42X1
ai4x«aae
0.1SX«OJO«
0.13X-ai4
0.13X-O03
0.15X40.67
0.13X40J6
0.14X«OA4
0.17X4.1^46
OJ3X
OJ2X
CL32X
O23X42J*
O26X4O41
fddwMk)
)t'*Expactid raooMty for OM or n
•.'•ExpccMd alngto amlyM tttndf
8*-E*»clKl \rttrtHxntorf stMKted dMtaUo
Q»Tn» vikM tor ttw oonomMion. In no/L.
XMvano* raoomy found tor imMuranMnte ol i
of
i of
I0f««
« «M pcrtormMM In • aingto tabcntocy.
^tcoanMninga
•t an Mragc concentration found
at n •Mrag* oononMaon found of
ng • conoantntlon of C. in itpA-
in|i0(L.
656
-------
Environmental Ptotocitert Agoney
PI. 136, App. A, Moth. 601
OPTIONAL
FOAM
TRAP
EXIT V* IN.
0. D.
—14MM 0. D,
INLET 1/4 IN.
0. D.
0. D. EXIT
SAMPLE INLET
* -
2-WAY SYRINGE VALVE
17CM. 20 GAUGE SYRINGE NEEDLE
. 0. D. RUBBER SEPTUM
10MM. 0. D. 1/16 IN. O.D.
\ySTAINLESS STEa
INLET
IN. 0. D.
10MM GLASS FRIT
MEDIUM POROSITY
13X MOLECULAR
SIEVE PURGE
GAS FILTER
PURGE GAS
FLOW
CONTROL
Figure 1. Purging device.
657
-------
Pt. 136, App. A, Moth. 601
PACKING PROCEDURE
40 CFR Ch. I (7-1-95 Edition)
CONSTRUCTION
GLASS
WOOL
ACTIVATED, „„ .
CHARCOAL 7.7CM
4
GRADE 15
SILICA GEL
7.7CM
TENAX 7.7 CM
GLASS
1
7 A /FOOT
RESISTANCE
WIRE WRAPPED
SOLID
(DOUBLE LAYER)
15CM.
7~/FOOT4-
RESISTANCE
WIRE WRAPPED
SOLID
(SINGLE LAYER)
8CNH
TRAP INLET
COMPRESSION
FITTING NUT
AND FERRULES
* • .
THERMOCOUPLE/
CONTROLLER
SENSOR
ELECTRONIC
TEMPERATURE
CONTROL
AND
PYROMETER
I TUBING 25CM
/ 0.105 IN. I.D.
0.125 IN. O.D.
STAINLESS STE
Figure 2. Trap packings and construction to include
desorb capability
658
-------
Protection AQoncy
CARRIER GAS FLOW CONTROL
PRESSURE REGULATOR
UQU.P
PURGE GAS
FLOW CONTROL \|—
13X MOLECULAR
SIEVE FILTER
.— CONFIRMATORY COLUMN
TO DETECTOR
*-- ANALYTICAL COLUMN
OPTIONAL 4-PORT COLUMN
. ~~~ SELECTION VALVE
6-PORT TRAP INLET
VA/VLrf// RESISTANCE WIRE
/S
HEATER CONTROL
PURGING
DEVICE
Not«:ALL LINES BETWEEN
TRAP AND GC
SHOULD BE HEATED
TO 80T
Figure 3. Purge and trap system-purge mode.
CARRIER GAS
FLOW CONTROL
PRESSURE
REGULATOR
PURGE GAS V(_i
FLOW CONTROLJj
13X MOLECULAR
SIEVE FILTER
I CONRRMATORY COLUMN
DTD DETECTOR
f ^-ANALYTICAL COLUMN
OPTIONAL 4*ORT COLUMN
SELECTION VALVE
6-PORT TRAP INLET
VALV^*SISTANCE™RE HEATER
^T TRAP /^^ CONTROL
IFLOW!—TBQOC
PURGING
DEVICE
Note:
ALL LINES BETWEEN
TRAP AND GC
SHOULD BE HEATED
TO 80°C.
Figure 4. Purge and trap system - desorb mode.
659
-------
owi
**!"•» ***•• • \*~|—>w taMMrw*!
CO
See
s
|C3 ut
3NVH130U01H3VU131-Z 'Z 'I'I
^i^^
3NVdCWdOa01HOIHi-e 7 'I
-2 4i
3NVHi30U01H3l}U -I'l'
3N3H13OaO1HDia-Z'
3N3H130a01HDia-t'l
3NVH13WOUO1HO
3N3dOUdOU01H3IQ-£'l • sum
3N3dOUdOU01HOIQ-E'l - <
660
-------
Environmental Protection Agency
ft. 136, App. A.
602
METHOD 002—POROEABLE ABOMATXCS
/. Scops and Application
1.1 This method covers the determination
of various purgeable aromatics. The follow-
ing parameters may be determined by this
method:
CMorabMiM*,
1,4-OlcMarebMaM
Bhyfcenana
TokMiw --,,••..-.........
STORET
Na
34030
34301
34638
34668
34671
34371
34010
CAS No.
71-43-4
108-85-7'
96-60-1
541-73-1
106-46-7
100-41-4
108-68-3
1.2 This is a purge and trap 'gas
chromatographic (OC) method applicable to
the determination of the compounds listed
above in municipal and industrial discharges
as provided under 40 CPU 136.1. When this
method is used to analyze
ples for any or all of the compounds above.
compound identifications should be sup-
ported by at least one additional Qualitative
technique. This method describes analytical
conditions for a second gas chromatographic
column that can be used to confirm measure-
ments made with the primary column. Meth-
od 624 provides gas chromatograph/mass
spectrometer (OG/M8) conditions appro-
priate for the qualitative and quantitative
confirmation of results for all of the param-
eters listed above.
1.3 The method detection limit (MDI*. de-
fined in Section 12.1) « for each parameter Is
listed In Table 1. The MDL for a specific
wastewater may differ from those listed, de-
pending upon the nature of interferences in
the sample matrix.
1.4 Any modification of this method, be-
yond those expressly permitted, shall be con-
sidered as a major modification subject to
application and approval of alternate test
procedures under 40 CFR 136.4 and 13&5.
1.5 This method is restricted to use by or
under the supervision of analysts experi-
enced In the operation of a purge and trap
system and a gas chromatograph and in the
interpretation of gas chromatograms. Each
analyst must demonstrate the ability to gen-
erate acceptable results with this method
using the procedure described in Section 8.2.
2. Summary of Method
-• 2.1 An inert gas is bubbled through a 5-mI*
water sample contained In a specially-de-
signed purging chamber at ambient tempera-
ture. The . aromatics are efficiently trans-
ferred from the aqueous phase to the vapor
phase. The vapor is swept through a sorbent
trap where the aromatics are trapped. After
purging is completed, the trap is heated and
backflushed with the Inert gas to desorb. the
aromatics onto a gas chromatographic col-
umn. The gas ehromatogmph is temperature
programmed to separate the aromatics
which are then detected, with a
photoionixatlon detector.2-3
&2 The method provides an optional gas
chromatographic column that may be help-
ful in resolving the compounds of interest
from interferences that may occur.
3. Interferences
3.1 Impurities in the purge gas and or-
ganic compounds ontgaseisg from the plumb-
ing ahead of the trap account for the major-
ity of contamination problems. The analyt-
ical system must be demonstrated to be free
from contamination under the conditions of
the analysis by running laboratory reagent
blanks as described In Section 8.1*3. The use
of non-Teflon plastic tubing. non-Teflon
thread sealants, or flow controllers with rub-
ber components in the purge and trap system
should be avoided.
32 Samples can be contaminated by diffu-
sion of volatile organics through the septum
tmp-1 into tfliE sample during shipment and
storage. A field reagent blank prepared from
reagent water and carried through the sam-
pling and handling protocol can serve as a
check on such contamination.
3.3 Contamination by carry-over can
occur whenever high level and low level sam-
ples are sequentially analysed. To reduce
carry-over, the purging device and sample
syringe must be rinsed with reagent water
between sample analyses. Whenever an un-
usually concentrated sample is encountered.
it Should be followed by an analysis of rea-
gent water to check for cross contamination.
For samples containing large amounts of
water-eolnble materials, suspended solids,
high boiling compounds or high aromatic
levels, it may be neceBmry to wash the purg-
ing device with a detergent solution, rinse it
with distilled water, and then dry it in an
oven at 105 *C between analyses. The trap and
other parts of the system are also subject to
contamination; therefore, frequent bakeout
and purging of the entire system may be re-
quired.
4. Safety
4J. The toxlclty or carcinogenicity of
each reagent used In this method has not
been precisely defined; however, each chemi-
cal compound should be treated as a poten-
tial health hazard. From this viewpoint, ex-
posure to these chemical* must be reduced to
the lowest possible level by whatever means
available. The laboratory is responsible for
a current awareness file of
OSHA regulations regarding the safe han-
dling of the chemicals specified in this meth-
od. A reference file of material data handling
sheets should also be made available to all
personnel involved in the chemical analysis.
Additional references, to laboratory safety
661
-------
W. 136, App. A, MOffl. 602
cn. i (7-
fcomon)
*re available and have been identified4-* for
the information of the analyst.
4.2 The following parameters covered by
this method have been tentatively classified
at known or suspected, human or mam-
malian carcinogens: benzene and 1,4-
dlchlorobenzene. Primary standards of these
toxic compounds should be .prepared in a
hood. A NIOSH/MESA approved toxic gas
reiplrator should be worn when the analyst
handles high concentrations of .these toxic
compounds.
• 5. Apparatus and Materials
5.1 Sampling equipment, for discrete sam-
pling.
5.1.1 VialJ25-mL capacity or larger,
equipped with a screw cap with a hole in the
center (Pierce #13075 or equivalent). Deter-
gent wash, rinse with tap and distilled water.
and dry at 106 *C before use.
5.1.2 Septum—Teflon-faced • silicons
(Pierce #12722 or equivalent). Detergent
wash, rinse with tap and distilled water, and
dry at 105'C for 1 h before use.
&2 Purge and trap system—The purge and
. trap system consists of three separate pieces
of equipment: A purging device, trap, and
desorber. Several complete systems are now
commercially available.
&3.1 The purging device must be designed
to accept 6-mIi samples with a water column
at least 3 cm deep. The gaseous head space
between the water column and the trap must
have a total volume of less than 15 mL. The
purge gas must pass through the water col-
umn as finely divided bubbles with a diame-
ter of less than 3 mm at the origin. The
purge gas must be introduced no more than
5 mm from the base of the water column.
The purging device illustrated in Figure 1
meets these design criteria.
5JL2 The trap must be at least 25 cm long
and have an inside diameter of at least 0.105
in.
5.2.2.1 The trap is packed with 1 cm of
methyl silloone coated packing (Section
6.4.2) and 23 cm of 2,6-diphenylene oxide poly-
mer (Section 6.4.1) as shown in Figure 2. This
trap was used to develop the method per-
formance statements in Section 12.
5.2.2.2 Alternatively, either of the two
traps described in Method 601 may be used,
although water vapor will preclude the meas-
urement of low concentrations of benzene.
5.2.3 The deeorber must be capable of rap-
idly heating the trap to 180 "C. The polymer
section of the trap should not be heated
higher than ISO *C and the remaining sec-
tions should not exceed 200 *C. The desorber
illustrated in Figure.2 meets these design
criteria.
5.2.4 The purge and trap system may be
assembled as a separate unit or be coupled to
a gas chromatograph as illustrated in Fig-
ures 3.4, and 5.
5.3 Gas chromatograph—An analytical
system complete with.a temperature pro-
grammable gas chromatograph suitable for
dn-column injection and all required acces-
sories including syringes, analytical col-
umns, gases, detector, and strip-chart re-
corder. A data system is recommended for
measuring peak areas. >.
5.3.1 .Column 1—6 ft. long x 0.082 in. ID
stainless steel or glass, packed with 5% 8P-
1200 and 1.75% Bentone-34 on Supelcoport
(100/120 mesh) or equivalent. This column
was used to develop the method performance
statements in Section 12. Guidelines for the
use of alternate column packings are pro-
vided in Section 10.1.
5.3.2 . Column 2—8 ft long x 0.1 in ID stain-
less steel or glass, packed with 5% 1&3-
Tris(2-cyanoethoxy)propane on Chrpmosorb
W-AW (60/80 mesh) or equivalent.
5.3.3. Detector—Photoionlzation detector
(h-Nu Systems, Inc. Model PI-51-02 or equiv-
alent). This type of detector has been proven
effective in the analysis of wastewatera for
the parameters listed in the scope (Section
1.1), and was used to develop the method per-.
fonnance statements in Section 12. Guide-
lines for the use of alternate detectors are
provided in Section 10.1.
5.4 Syringes—6-tnL glass hypodermic with
Luerlok tip (two each), if applicable to the
purging device.
5.5 Micro syringes—25-|iL. 0.006 in. ID nee-
dle.
5.6 Syringe valve—2-way, with Luer ends
(three each). .
5.7 Bottle—15-mL, screw-cap, with Teflon
cap liner. .
5.8 Balance—Analytical, capable of accu-
rately weighing 0.0001 g.
6. Reagents
.6.1 Reagent water—Reagent water is de-
fined as a water in which an interferent is
not observed at the MDL of the parameters
of Interest.
6.1.1 Reagent water can be generated by
passing tap water through a carbon filter bed
containing about 1 Ib of activated carbon
(Filtrasorb-300, Calgon Corp., or equivalent).
6.1.2 A -water purification system
(Mllllpore Super-Q or equivalent) may be
used to generate reagent water.
6.1.3 Reagent water may also be prepared
by boiling water for 15 min. Subsequently.
while maintaining the temperature at 90 •C,
.bubble a contaminant-free inert gas through
the water for 1 h. While still hot, transfer
the water to a narrow mouth screw-cap bot-
tle and seal with a Teflon-lined septum and
cap.
6.2 Sodium thiosulfate—(ACS) Granular.
6.3 Hydrochloric acid (1+1>—Add 50 mL of
concentrated HC1 (ACS) to 50 mL of reagent
water.
6.4 Trap Materials:
662
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Environmental Protection Agency
6.4.1 2,6-Diphenylene oxide polymer—.
Tenaz,. (GO/BO mesh), chromatographic grade
or equivalent. . • .
6.4.2 Methyl silicone packing:—3% OV-1 on
•Chromosorb-W (60/80 mesh) or equivalent.
6.5 Methanql—Pesticide quality or equiv-
alent.
6.6 Stock standard solutions—Stock
standard .solutions may be prepared from
pure standard materials or purchased as cer-
tified solutions. Prepare stock standard solu-
tions in methanol using assayed liquids. Be-
cause of the tozicity of benzene and 1,4-
dichlorobenzene. primary dilutions of these
materials should be prepared in a hood. A
NIO8H/MESA approved toxic gas respirator
should be used when the analyst handles
high concentrations of such materials.
6.6.1 Place about 9.8 mL of methanol into
a 10-mL ground glass stoppered volumetric
flask. Allow the flask to stand, unstoppered,
for about 10 min or until all alcohol wetted
surfaces have dried. Weigh the flask to the
nearest 0.1 mg.
6.&2 Using a 100-fiL syringe, immediately
add two or more drops of assayed reference
material to the flask, then reweigh. Be sure
that the drops fall directly into the alcohol
without contacting the neck of the flask.
6.6.3 Reweigh. dilute to volume, stopper,
then mix by inverting the. flask several
times. Calculate the concentration in |ig/|iL
from the net gain in weight. When compound
purity is assayed to be 96% or greater, the
weight can be used without correction to cal-
culate the concentration of the stock stand-
ard. Commercially prepared stock standards
can be used at any concentration if they are
certified by the manufacturer or by an inde-
pendent source. •
6.6.4 Transfer the stock standard solution
into a Teflon-sealed screw-cap bottle. Store
at 4 *C and protect from light.
• 6.6J» All standards must be replaced after
one month, or sooner if comparison with
check standards indicates a problem.
6.7 Secondary dilution standards—Using
stock standard solutions, prepare secondary
dilution standards in methanol that contain
the compounds of interest, either singly or
mixed together. The secondary dilution
standards should be prepared at concentra-
tions such that the aqueous calibration
standards prepared in Section 7.3.1 or 7.4.1
will bracket the working range of the ana-
lytical system. Secondary solution standards
must be stored with zero headspace and
should be checked frequently for signs of
degradation or evaporation, especially just
prior to preparing calibration standards from
them.
6.8 Quality control check sample con-
centrate—See Section 8.2.1.
7. CoHiratton
7.1 Assemble a purge and trap system that
meets the specifications in Section 5.2. Con-
Pt. 136, App. A, Meta. 602
dition the trap overnight at 180 *C by
backflushing with an inert gas flow of at
least 20 mL/min. Condition the trap for 10
min once daily prior to use.
7.2 Connect the purge and trap system to
a gas chrbmatograph. The gas chro-
matograph must be operated using tempera-
ture and flow rate conditions equivalent to
those given in Table 1. Calibrate the purge
and trap-gas chromatographic system using
either the external standard technique (Sec-
tion 7.3) or the internal standard technique
(Section 7.4).
7.3 External standard calibration proce-
dure:
7.3.1 Prepare calibration standards at a
minimum of three concentration levels for
each parameter by carefully adding 20.0 |iL of
one or more secondary dilution standards to
100, 500, or 1000 mL of reagent water. A 25-pL
syringe with a 0.006 in. ID needle should be
used for this operation. One of the external
standards should be at a concentration near.
but above, the MDL (Table 1) and the other
concentrations should correspond to the ex-
pected range of concentrations found in real
samples or should define the working range
of the detector. These aqueous standards
must be prepared fresh daily.
7.3.2 Analyze each calibration standard
according to Section 10. and tabulate peak
height or area responses versus the con-
centration in the standard. The results can
be used to prepare a calibration curve .for
each compound. Alternatively, if the ratio of
response to concentration (calibration fac*
tor) is a .constant over the working range
(<10% relative standard deviation. BSD), lin-
earity through the origin can be assumed
and the average ratio or calibration factor
can be used in place of a calibration curve.
7.4 Internal standard calibration proce-
dure—To use this approach, the analyst must
.select one or more internal standards that
are similar in analytical behavior to the
compounds of interest. The analyst must fur-
ther demonstrate that the measurement of
the internal standard is not affected by
method or matrix interferences. Because of
these limitations, no internal standard can
be suggested that is applicable to all sam-
ples. The compound, aAO,-trlfluorotoluene,
recommended as a surrogate spiking
compound in Section 8.7 has been used suc-
• cessfully as an internal standard.
7.4.1 Prepare calibration standards at a
minimum of three concentration levels for
each parameter of interest as described in
Section 7.3.1.
7.4.2 Prepare a spiking solution contain-
ing each of the Internal standards using the
procedures described in Sections 6.6 and 6.7.
It is recommended that'the secondary dilu-
tion standard be prepared at a concentration
of 15 iig/mL of each internal standard
compound. The addition of 10 |iT of this
-------
W. 136, App. A, Melh. 602
standard to 5.0 mL of sample or calibration
standard would be equivalent to 30 |ig/L.
7.4.3 Analyze each calibration standard
according' to Section 10, adding 10 |iL of in-
ternal standard* spiking solution directly to
the syringe (Section 10.4). Tabulate peak
height or area responses against concentra-
tion for each compound and internal stand-
ard, and calculate response factors (BF) for
ftgfft compound T'ffoB' Equation 1.
(AuXC.)
Equation 1
where:
A«*Besponse for the parameter to be meas-
ured.
Afe«Besponse for the internal standard.
Ctt*Conoentration of the internal standard
C.»Conoentration. of the parameter to be
measured.
If the BF value over the working range is a
constant (<10% BSD), the BF can be assumed
to be invariant and the average BF can be
used for calculations. Alternatively, the re-
sults can be used to plot a calibration curve
of response ratios, AJAu, vs. BF.
7.5 The working calibration curve, cali-
bration factor, or BF must be verified on
each working day by the measurement of a
QC check sample.
7.5.1 Prepare the QC check sample as de-
scribed in Section 8JL2.
7J>Jt Analyze the QC cheek sample accord-
ing to Section* 10.
7Jx3 For each parameter, compare the re-
sponse (Q) with the corresponding calibra-
tion acceptance criteria found in Table 2. If
the responses for all parameters of Interest
fall within the designated ranges, analysis of
actual samples can begin. If any individual Q
falls outside the range, a new calibration
curve, calibration factor, or BF must be pre-
pared for that parameter according to Sec-
tion 7.3 or 7.4.
8. Quality Control
8.1 f$*f** laboratory that uses this method
is required to operate a formal quality con-
trol program. The Tn<*«<™"» requirements
of this program consist of'an initial dem-
onstration of laboratory capability and an
ongoing analysis of spiked samples to evaln-
* ate and document data quality. The labora-
tory must w»«"t-AiT» records to document the
quality of data that is generated. Ongoing
data quality checks are compared with es-
tablished performance criteria to determine
if the results of analyses meet the perform-
•anoe characteristics of the method. When re-
sults of sample spikes indicate atypical
method performance, a quality control check
standard most be analyzed to confirm that
40 CFR Ch. I (7-1-95 Edition)
the measurements were performed in an in-
control mode of operation.
8.1.1 The analyst must make an initial,
one-time, demonstration of the ability' to
generate acceptable accuracy and precision
with this method. This ability is established
as described in Section 8.2.
8.1.2 In recognition of advances that are
occurring in chromatography. the analyst is
permitted certain options (detailed in Sec-
tion 10.1) to improve the separations or lower
the cost of measurements. Each time such a
modification is made to the method, the ana-
lyst is required to repeat the procedure in
Section 8.2.
8.1.3 Each day. the analyst must analyze a
reagent water blank to demonstrate that
interferences from the analytical system are
under control.
8.1.4 The laboratory must, on an ongoing
basis, spike and analyze a mirtmnm of 10%
of all samples to monitor and evaluate lab-
oratory data quality. This procedure is de-
scribed in Section 8.3,
8.1.5 The laboratory must, on an ongoing
basis, demonstrate through the analyses of
quality control check standards that the op-
eration of the measurement system is in con-
trol. This procedure is described in Section
8.4. The frequency of the check standard
analyses is equivalent to 10% of all samples
analyzed but may be reduced if spike recov-
eries from samples (Section 8.3) meet all
specified quality control criteria.
8J.6 The laboratory must maintain per-
formance records to document the quality of
data that is generated. This procedure is de-
scribed in Section 8.5.
62 To establish the ability to generate
acceptable accuracy and' precision, the ana-
lyst must perform the following operations.
A quality control (QC) check sample
concentrate is required containing each pa-
rameter of interest at a concentration of 10.
Hf/rnT. in methanol. The QC check sample .
concentrate must be obtained from the U.8.
Environmental Protection Agency. Environ- .
mental Monitoring and Support Laboratory
in Cincinnati, Ohio, if available. If not avail-
able from that source, the QC check sample
concentrate must be obtained from another
external source. If not available from either
source above, the QC check sample con-
centrate must be prepared by the laboratory
qytog stock standards prepared independ-
ently from those used for calibration.
8^2 Prepare a QC check sample to con-
tain 20 jig/L of each parameter by adding 200
pL of QC check sample concentrate to 100 mL
of reagant water.
8^3 Analyze four 5-mL aliqnots of the
well-mixed QC check sample according to
Section 10.
8£.4 Calculate the average recovery (X) in
lig/L. and the standard deviation of the re-
covery (s) in MS/L. for each parameter of in-
teract using toe four results.
664
-------
Environmental Protection Agency
8.2.5 'For each parameter compare s and X
with the 'corresponding acceptance criteria
for precision -and accuracy, respectively.
found In Table 2. If a and X for all param-
eters of Interest meet the acceptance cri-
teria. the system performance is acceptable
and analysis of actual samples can begin. If
any individual s exceeds the precision limit
or any individual X falls outside the range
for accuracy, the system performance is un-
acceptable for that parameter.
'NOTE: The large number of parameters in
Table 2 present a substantial probability
that one or more will fall at least one of the
acceptance criteria when all parameters are
analyzed.
8.2.6 When one or more of the parameters
tested fail at least one of the acceptance cri-
teria, the analyst must proceed according to
Section 8.2.6.1 or 8.2.6.2. .
8.2.6.1 Locate and correct the source of
the problem and repeat the test for all pa-
rameters of interest beginning with Section
8.2.6.2 Beginning with Section 8 A3. repeat
the test only for those parameters that
failed to meet criteria. Repeated failure.
however, will confirm a general problem
with the measurement system. If this occurs.
locate and correct the source of the problem
and repeat the test for all compounds of In-
terest beginning with Section 8.2.3.
8.3 The laboratory must, oh an ongoing
basis, spike at least 10% of the samples from
each sample site being monitored to assess
accuracy. For laboratories analyzing one to
ten samples per month, at least one spiked
sample per month is required.
8.3.1 The concentration of the spike in the
sample should be determined as follows:
8.3.1.1 If, as in compliance monitoring,
the concentration of a specific parameter in
the sample is being checked against a regu-
latory concentration limit, the spike should
be at that limit or 1 to 5 times higher than
the background concentration determined In
Section 8.3.2, whichever concentration would
be larger.
8.3.1.2 If the concentration of a specific
parameter in the sample is not being
checked against a limit specific to that pa-
rameter. the spike should be at 20 |ig/L or 1
to 5 times higher than the background con-
centration determined in Section 8.3.2.
whichever concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to
determine the background concentration (B)
of each parameter. If necessary, prepare a
new QC check sample concentrate (Section
8.2.1) appropriate for the background con-
centrations in the sample. Spike a second 5-
mL sample aliquot with 10 i»L of the QC
check sample concentrate and analyze it to
determine the concentration after spiking
(A) of each parameter. Calculate each per-
cent recovery (P) as 100(A-B)%/T, where T is
the known true value of the spike.
8.3.3 Compare the percent recovery (P) for
each parameter with the corresponding QC
acceptance criteria found in Table 2. These
acceptance criteria were calculated to in-
clude an allowance for error in measurement
of both the background and spike concentra-
tions, ftwroming a spike to background ratio
of 5:1. This error will be accounted for to the
extent that the analyst's spike to back-
ground ratio approaches 5:1.7 If spiking was
performed at a concentration lower than 20
lig/L, the analyst must use either the QC ac-
ceptance criteria in Table 2. or optional QC •
acceptance criteria calculated for the spe-
cific spike concentration. To calculate op-
tional acceptance criteria for the recovery of
a parameter: (1) Calculate accuracy (X*)
using the equation in Table 3, substituting
the spike concentration (T) for C; (2) cal-
culate overall precision (S') using the equa-
tion in Table 3, substituting X' for X; (3) cal-
culate the range for recovery at the spike
concentration as (100 X'/T) ± 2.44(100 SVT)%.7
8.3.4 If any individual P falls outside the
designated range for recovery, that param-
eter has failed the acceptance criteria. A
check standard containing each parameter
that failed the criteria must be analyzed as.
described in Section 8.4.
8.4 If any parameter fails the acceptance
criteria for recovery in Section 8.3, a QC
check standard containing each parameter
that failed must be prepared and analyzed.
NOTK The frequency for the required anal-
ysis of a QC check standard will depend upon
the number of parameters being simulta-
neously tested, the complexity of the sample
matrix, and the performance of the labora-
tory.
8.4.1. Prepare the QC check standard by
ftfrflug 10 jiL of QC check sample concentrate
(Section 8.2.1 or 8^2) to 5 mL of reagent
water. The QC check standard needs only to
contain the parameters that failed criteria
in the test in Section 8.3.
8.4.2 Analyze the QC check standard to
determine the concentration measured (A) of
each parameter. Calculate each percent re-
covery (P.) as 100 (A/T)%. where T Is the true
value of the standard concentration.
8.4.3 Compare the percent recovery (P.)
for each parameter with the corresponding
QC acceptance criteria found in Table 2. Only
parameters that failed the test in Section 8.3
need to be compared with these criteria. If
the recovery of any such parameter falls out-
side the designated range, the laboratory
performance for that parameter is Judged to
be out of control, and the problem must be
Immediately identified and corrected. The
analytical result for that parameter in the
unspiked sample is suspect and may not be
reported for regulatory compliance purposes.
8.5 As part of the QC program for the lab-
oratory, method accuracy for wastewater
665
-------
W. 136, App. A, M«!h. 602
samples must be asiessod and records must
be maintain^ i After the analysis of five
spiked wastewater samples as in Section 8J3.
calculate the average percent recovery (P)
and the standard deviation of the percent re-
covery (a,). Bjuyess the accuracy assessment
as a percent recovery interval from P-2a, to
P+2v If P*90V« and 8p=10V., for example, the
accuracy interval is expressed as 70-110%.
Update the accuracy assessment for each pa-
rameter on a regular basis (e.g. after each
five to ten new accuracy measurements).
8.6 it is recommended that the laboratory
adopt additional quality assurance practices
for use with this method. The specific prac-
tices that are most productive depend upon
the needs of the laboratory and .the nature of
the samples. Field duplicates may be ana-
lysed to assess the precision of the environ-
mental measurements. When doubt exists
over the identification of a peak on the chro-
matograni. confirmatory techniques such as
gas chromatography with a dissimilar col-
umn, specific element detector, or mass
spectrometer must be used. Whenever pos-
sible, the laboratory should analyze standard
reference materials and participate in rel-
evant performance evaluation studies.
8.7 The analyst should monitor both the
performance of the analytical system and
the effectiveness of the method in dealing
with each sample matrix by spiking each
sample, standard, and reagent water blank
with surrogate compounds (e.g. 0,0,0*-
trifluorotoluene) that encompass the range
of the temperature program used in this
method. From stock standard solutions pre-
pared as in Section 6.6. add a volume to give"
760 |ig of each surrogate to 45 mL of reagent
water contained in a 50-mL volumetric flask.
mHy and dilute to-volume for a concentration
of 15 mg/iiL. Add 10 ML of this surrogate spik-
ing solution directly into the 5-mL syringe
with every sample and reference standard
analyzed. Prepare a fresh surrogate spiking
solution on a weekly basis. If the internal
standard calibration procedure is being used.
the surrogate compounds may be added di-
rectly to the internal standard spiking solu-
tion (Section 7.4.2).
9. Sample Collection, Preservation, and
Handling
9.1 The samples must be iced pr refrig-
erated from the time of collection until anal-
ysis. If the sample contains free or combined
chlorine, add sodium thioaulfate preserva-
tive (10 mg/40 TT»T- is -sufficient for up to 5
ppm Cla) to .the empty sample bottle Just
prior to shipping to the sampling site. EPA
Method S30.4 or 330.5 may be used for meas-
urement of residual chlorine.* Field test kits
are available for this purpose.
9.2 Collect about 500 mL of sample in a
clean container. Adjust the pH of the sample
to about 2 by adding 1+1 HC1 while stirring.
Fill the sample bottle in such a manner that
40 CFR Ch. I (7-1-95 EdHton)
no air bubbles pass through the sample as
the bottle is being filled. Seal the bottle so
that no air bubbles are entrapped in it. Main-
tain the hermetic seal on the sample bottle
until time of analysis.
9.3 All samples must be analysed within
14 days of collection.1
10. Procedure
10.1 Table 1 unrnTnurliw* thg rtfaffininendfld
operating conditions for the gas chrom-
atograph. Included in this table are esti-
mated retention times and MDL that can be
achieved under these conditions. An example
of the separations achieved by Column 1 is
shown in Figure 6. Other packed columns.
chromatographic conditions, or detectors
may be used if the requirements of Section
8.2 are met.
10.2 Calibrate the system daily as de-
scribed in Section 7.
10.3 Adjust the purge gas (nitrogen or he-
lium) flow rate to 40 mL/min. Attach the
trap inlet to the purging device, and set the
purge and trap system to purge (Figure 3).
Open the syringe valve located on the purg-
ing device sample introduction needle.
10.4 Allow the sample to come to ambient
temperature prior to introducing it to the
gyring*- Remove the plunger from a 5-mL sy-
ringe and attach a closed syringe valve. Open
the sample bottle (or standard) and carefully
pour the sample into the syringe barrel to
Just short of overflowing. Replace the sy-
ringe plunger and compress the sample. Open
the syringe valve and vent any residual air
while adjusting the sample volume to 5.0 mL.
Since this process of taking an aliquot de-
stroys the validity of the sample for future
analysis, the analyst should fill a second sy-
ringe at this time to protect against possible
loss of data. Add 10.0 pL of the surrogate
spiking solution (Section 8.7) and 10.0 pL of
the internal standard spiking solution (Sec-
tion 7.4£). if applicable, through the valve
bore, then close the valve.
10.5 Attach the syringe-syringe valve as-
sembly to the syringe valve on the purging
device. Open the syringe valves and-inject
the sample into the purging chamber.
10.6 Close both valves and purge the sam-
ple for 12.010.1 min at ambient temperature.
10.7 After the 12-xnin purge time, dis-
connect the purging device from the trap.
Dry the trap by maintaining a flow of 40 mL/
min of dry.-purge gas through it for 6 min
(Figure 4). If the purging device has no provi-
sion for bypassing the purger for this step, a
dry purger should be inserted into the device
to m1niT"<"> moisture in the gas. Attach the
trap to the chromatograph. adjust the purge
and trap system to the desorb mode (Figure
5), and begin to temperature program the gas
chromatograph. Introduce the .trapped mate-
rials to the GC column by rapidly heating
the trap to 180 *C while backflushing the trap
with an inert gas between 20 and 60 tnT/ntln
666
-------
Envfronmonfd ftoteteflon Agency
for 4 min. If rapid heating of the trap cannot
be achieved, the GC column must be used as
a secondary trap by cooling it to 30 *C
(snbambient temperature, if poor peak geom-
etry and random retention time problems
persist) instead of the initial program tem-
perature of 50 *C.
10.8 While the trap is being desorbed into
the gas chromatograph column, empty the
purging chamber using the sample introduc-
tion syringe. Wash the chamber with two 5-
mL flushes of reagent water.
10.9 After desorblng the sample for 4 min.
recondition the trap by returning the purge
and trap system to the purge mode. Wait 15
a. then close the syringe valve on the purg-
ing device to begin gas now through the
trap. The trap temperature should be main-
tained at 180 "C. After approximately 7 mln.
turn off the trap heater and open the syringe
valve to stop the gas flow through the trap.
When the trap is cool, the next sample can
be analysed.
10.10 Identify the parameters in the sam-
ple by comparing the retention times of the
peaks in the sample chromatogram with
those of the peaks in standard
chromatograms. The width of the retention
time window used to make identifications
should be based upon measurements of ac-
tual retention time variations of standards
over the course of a day. Three times the.
. standard deviation of a retention time for a
compound can be used to calculate a sug-
gested window size; however, the experience
of the analyst should weigh heavily, in the
interpretation of chromatograms.
1001 If the response for a peak exceeds
the working range of the system, prepare a
dilution of the sample with reagent water
from the aliquot in the second syringe and
reanalyze.
11J. Determine the concentration of Indi-
vidual fftMiip?***1*^* in the sample.
11.1.1 If the external standard calibration
procedure is used, calculate the concentra-
tion of the parameter being measured from
the peak response using the calibration
curve or calibration factor determined in
Section 7.34. •
11.1.2 If the Internal standard calibration
procedure is used, calculate the concentra-
tion in the sample using the response factor
(RF) determined in Section 7.4.3 and Equa-
tion 2.
Concentration .(|ig/L)
(A.MC..)
Equation 2
where:
A. = Response for the parameter to be
measured. .
Pt.
A*. = Response for the internal standard.
Cb = Concentration of the Internal stand-
ard. .
11.2 Report results in |ig/L without correc-
tion for recovery data. All QC data obtained
should be reported with the sample results.
12. Method Performance
12.1 The method detection limit (MDL) is
defined as the minimum concentration of a
substance that can be measured and reported
with 99% confidence that the value is above
zero.1 The MDL concentrations listed in
Table 1 were obtained using reagent water.*
•Similar results were achieved using rep-
resentative wastewaters. The MDL actually
achieved in a given analysis will vary de-
pending on instrument sensitivity and ma-
trix effects.
12£ 'This method has been demonstrated
to be applicable for the concentration range
from the MDL to 100 X MDL.* Direct aqueous
injection techniques should be used to meas-
ure concentration levels above 1000 x MDL.
1X3 This method was tested by 20 labora-
tories using reagent water, drinking water.
surface water, and three Industrial
wastewaters spiked at six concentrations
over the range 2J to 550 |ig/L.* Single opera-
tor precision, overall precision, and method
accuracy were found to be directly related to
the concentration of the parameter and es-
sentially Independent of the sample matrix.
Lftmar equations to describe these relation-
ships are presented in Table 3.
Reference*
1. 40 CPR part 136. appendix B.
2. Uchtenberg. J-J- "Determining Volatile
. Organics at Mlcrogram-per-Litre-Levels by
Gas Chromatography." Journal American
Water Works Association. 66, 739 (1974).
3. Bellar, TJL. and Uchtenberg. J.J.
"Semi-Automated Headspsse Analysis of •
Drinking Waters and Industrial Waters for
Purgeable Volatile Organic Compounds."
Proceedings of Symposium on Measurement
of Organic Pollutants in Water and
Wastewater. American Society for Testing
and Materials. STP 688. CJ3L Van Hall, edi-
tor. 1978.
4. "Carcinogens— Working with Carcino-
gens." Department of Health. Education, and
Welfare. Public Health Service, Center for
Disease Control. National Institute for Occu-
pational Safety and Health. Publication No.
77-206. August 1977.
5 "O8HA Safety and Health Standards.
General Industry," (29 CPR part 1910), Occu- .
pational Safety and Health Administration,
OSHA 2206 (Revised, January 1976).
6. "Safety in Academic Chemistry Labora-
tories," American Chemical Society Publica-
tion. Committee on Safety. 3rd Edition. 1979.
. 7. Provost, L.P., and Elder, R.S. "Interpre-
tation of Percent Recovery Data." American
667
-------
40 CFR Ch. I (7-1-95 EdWon)
TABLE 1—CHROMATOGRAPWC COWOTJONS AND
METHOD DETECTION LIMITS
Rfllntlon HflM (fnin)
Column 1
Sl75
CWorob.
IXXcNorobanzarw
1,3-OfcMorabaniana,
12-OtaMorebanxana
9.17
1&B
182
2&9
Column 2
(WD
Pt. 136, App. A, Moth. 602
Laboratory. 25, 68-63. (1963). (The value 2.44
used. In the equation In Section 8.&S. is two
times the Value 1.22 derived in this report.)
i."Methods 330.4 cntrimetric. DFD-FA8)
and 891X6 (Spectrophotometric, DFD) for
Chlorine. Total Residual," Methods for
Chemical Analysis of Water and Wastes.
BPA-flOW-TO-CSO. U.S. Environmental Pro-
tection Agency, Office of Research and De-
velopment, Environmental Monitoring and
Support Laboratory. Cincinnati. Ohio 45388.
March 1879.
9. "EPA Method Study 25. Method 602.
Pnrreable Aromatics," EPA 600/4-44-042. Na-
tional Technical Information Service, PB84-
190682. Springfield, Virginia 22161. May 1984.
gaa si 30 mLftrtn tow rate. Column temparatum haU at 40
£~fer2min than pmgrammad at 2 «C/min to 100 «C tar a
Snal nOKL
TABLES-CALIBRATION AND QC ACCEPTANCE CRITERIA—METHOD 602«
2.75
425
628
842
182
1&0
1A4
02
02
02
02
04
IM
IM
Column 1 eonolttoni; Supateoport (100/120 mash) __„_
W*^WMWB*toM*4 paekad to iel'x^SK
-. -~~--
MriipreonnMMdst8-CA* to90«C tor• final hold.
Column 2 eonoWom: CnmmoMib W^-AW (8QIBO
^sWnfldr
Ct>*ofrt;Ojj?3
0.18X40.71
X'-Expaclad racovary for ana or
•'•rirr^nt»1 rinnlj •n«ln«l •
«
C-Tru* VM
X-Aw»o>
itaanatyitatandanjdavteUonotf
rsfary atandanl OavteSon of
^— *--- •• i_ .._•
'-~-t-m.*mj HWKwranry mBK^u UWMa
-Trua vaiua for tha ConoanMtan. to pa/L.
-*—~i raowary *ound fcr maaauramanta of aamptea eenMnbio a
at an avaraga oonoantratton
-atanavanoaoon—"-*•-
n o(C. in
mtnbondC.ini^L.
-------
Environmental Protection Agency
Pt. 136, App. A, Mottk. 601
OPTIONAL
FOAM
TRAP
EXIT tt IN.
0. D.
-*-14MM 0. D.
INLETS IN.
0. D.
% IN.
0, D. EXIT
SAMPLE INLET
2-WAY SYRINGE VALVE
17CM. 20 GAUGE SYRINGE NEEDLE
6MM. 0. D. RUBBER SEPTUM
~10MM. 0. D.
INLET
IN. 0. D.
1/16 IN. O.D.
y STAINLESS STEEL
13X MOLECULAR
SIEVE PURGE
GAS FILTER
10MM GLASS FRIT
MEDIUM POROSITY
PURGE GAS
FLOW
CONTROL
Figure 1. Purging device.
669
-------
Pi. 136, App. A. MMft. 602
40 CFB Ch. I (7-1-9S EdMon)
PACKING PROCSXIRE
GLASS
WOOL
TBIAK 23CU
3%OV-11CU
GLASS WOOL
CONSTRUCTION
COMPRESSION FITTING
NUT AND FERRULES
14FT.7A/FOOT RESISTANCE
WIRE WRAPPED SOLID
THERMOCOUPLE/
CONTROLLBt
'SBISOR
ELECTRONIC
TEMPERATURE
CONTROL
AND
PYROMETER
C / TUBING 25CM.
0.105 IN. I.Do
0.125 IN. O.D.
STAINLESS STEEL
TRAP INLET
Figure 2. Trap packings and construction to include
desorb capability. .
670
-------
Environmental Protection Agency
Carrier Gas Row Control Liquid Injection Ports
Pressure Regulator
\
Purge Gas
Row Control \r—
13X Molecular
Sieve Filter
Vah/e-3
Optional 4-Port Column
Selection Valve
lnlet
Resistance
Pt. 136. App. A. Meih. 602
> Column Oven
• ._ Confirmatory Column
To Detector
"***Analytical Column
. Heater Control
Note: All Lines Between
Trap and GC
Should be Heated
to 80°C
Figure 3. Purge and trap/system - purge mode.
Carrier Gas Row Control
Pressure Regulator
Liquid Injection Ports
Purge Gas
Row Control
13X Molecular
Sieve Filter
Column Oven
_^^"
• ___ Confirmatory Column
To Detector
I "*-—Analytical Column
Valve-3
Optional 4-Port Column
Selection Valve
Trap Inlet (Tenax End)
Resistance Wire
Trap
22°C
Heater Control
Vah/e-2
Note: All Lines Between
Trap and GC
Should be Heated
to 80°C
Figure 4. Purge and trap system-dry mode.
671
-------
Pt. 136, App. A, Moth. 602
Carrier Gas Flow Control Liquid Injection Ports
Pressure Regulator
JK
Purge Gas
Flow Control \T~
13X Molecular
Steve Fitter
Vah/e-3
Optional 4-Port Column
Selection Valve
Inlet (Tenax End)
Resistance Wire
40 CFR Ch. I (7-1-95 Edition)
Column Oven
—_ Confirmatory Column
To Detector
"""^ Analytical Column
Heater Control
Note: All Lines Between
Trap and GC
Should be Heated
to80°C
Valve-2
Figure 5. Purge and trap system-desorb mode.
Column: 5% SP 1200/1.75% Bantone - 34
en Supeleoport
Program: SO°C for 2 min, 6°C/min to 90°C
.Detector: Photoionization, 10.2 V
§
02 4 6 8 10 12 14 16 18 20 22 24 26 28
Retention Time. Min.
_ Figure 6. Gas chromatogram of purgeable aromaties.
672
-------
Environmental Protection Agency
METHOD 603—AcHOLEm AND ACBYLONTTWLE
• 1. Scope and Application
1.1 This method covers the determination
of acrolein and acrylonitrlle. The following
parameters may be determined by this meth-
od:
Fp~r
Acreliln „ ,
Aciyterttrta '.
STORET
No.
34210
34215
CAS No.
107-02-6
107-13-1
1.2 This is a purge and trap gas
chromatographic (GC) method applicable to
the determination of the compounds listed
above in municipal and industrial discharges
as provided under 40 CFB 138.1. When this
method is used to analyse mifl""*H»J sam-
ples for either or both of the compounds
above, compound identifications should be
supported by at least one additional quali-
tative technique. This method describes ana-
lytical conditions for a second gas
chromatographic column that can be used to
confirm measurements made with the pri-
mary column. Method 621 provides gas chro-
matograph/mass spectrometer (GC/MS) con-
ditions appropriate for the qualitative and
quantitative confirmation of results for the
parameters listed above, if used with the
purge and trap conditions described in this
method.
1.3 The method detection limit (MDL, de-
fined in Section 12.1)' for each parameter is
listed in Table 1. The MDL for a specific
wastewater may differ from those listed, de-
pending upon the nature of interferences in
the sample matrix.
1.4 Any modification of this method, be-
yond those expressly permitted, shall be con-
sidered as a major modification subject to
application and approval of alternate test
procedures under 40 CPE 136.4 and 13&5.
1.6 This method is restricted to use by or
under the supervision of analysts experi-
enced in the operation of a purge and trap
'system and a gas chromatograph and in the
interpretation of gas chromatograms. Each
analyst must demonstrate the ability to gen-
erate acceptable results with this -method
using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL
water sample contained in a heated purging
chamber. Acrolein and acrylonitrlle are
transferred from the aqueous phase to the
vapor .phase. The vapor is swept through a
sorbent trap where the analytes are trapped.
After the purge is completed, the trap is
heated and backflushed with the inert gas to
desorb the compound onto 2. jas
chromatographic column. The gas chro-
matograph is temperature programmed to
Pf. 136, App. A. M&th.
-------
Pt. 136, App. A, M9fo. 603
40 CFR Ch. I (7-1-45 EdWon)
. 5. Apparatu* and Material*
6J Sampling equipment, for discrete sam-
pling.
6.1.1 Vial—25-mL capacity or larger,
equipped with a screw cap with a bole In the
center (Pierce #18075 or equivalent). Deter-
rent wash, rinse with tap and distilled water.
and dry at 106 *C before use.
6.1.2 Septum—Tenon-faced slUcone
(Pierce #12132 or equivalent). Detergent
wash, rinse with tap and distilled water and
dry at 106 "C for l h before use.
&2 Purge and trap system—The purge and
trap system consists of three separate pieces
of equipment: a purging device, trap, and
desorber. Several complete systems are now
commercially available.
SA1 The purging device must be designed
to accept 6-mL, samples with a water column
at least S cm deep. The gaseous head space
between the water column and the trap must
have a total volume of less than 15 mL. The
purge gas must pass through the water col-
umn as finely divided bubbles with a diame-
ter of less than 3 mm at the origin. .The
purge gas must be introduced no more than
5 mm from the base of the water column.
The purging device must be capable of being
heated to 85 «C within 3.0 min after transfer
of the sample to the purging device and
being held at 85 i2 *C during the purge cycle.
The entire water column in the purging de-
vice must be heated. Design of this modifica-
tion to the standard purging device is op-
tional, however, use of a water bath is sug-
gested.
. &2.1J Heating mantle—To be used to heat
water bath.
&2.L2 Temperature controller—Equipped
with thermocouple/sensor to accurately con-
trol water bath temperature to 12 "C. The
purging device illustrated in Figure 1 meets
these design criteria.
5^2 The trap must be at least 25 cm long
and have an inside diameter of at least 0.105
in. The trap must be packed to contain 1.0
cm of methyl silicons coated packing (Sec-
tion 6.5.2) and 23 cm of 2.6-dlphenylene oxide
polymer (Section 6.5.1). The m^Ttinm speci-
fications for the trap are illustrated in Fig-
ure 2.
5.2.3 The desorber must be capable of rap-
Idly heating the trap to 180 *C, The desorber
Illustrated in Figure 2 meets these design
criteria.
5.2.4 The purge and trap system may be
assembled as a separate unit as illustrated in
Figure 3 or be coupled to a gas chro-
matograph.
5.3 pH paper—Narrow pH range, about 3.5
to 5.5 (Fisher Scientific Short Range Alkacid
No. 2, #14-837-2 or equivalent).
. 5.4 Gas chromatograph—An analytical
system complete with a temperature pro-
grammable gas chromatograph suitable for
on-column Injection and all required acces-
sories including syringes, analytical col-
umns, gases, detector, and strip-chart re-
corder. A data system is recommended for
measuring peak areas.
6.4.1 Column 1—10 ft long z 2 mm ID glass
or stainless steel, packed with Porapak-Q8
(80/100 mesh) or equivalent. This column was
used to develop-, .the method performance
statements in Section 12. Guidelines for the
use of alternate column packings are pro-
vided in Section 10.1.
5.4.2 Column 2—6 ft long z 0.1 in. ID glass
or stainless steel, packed with Chromosorb
101 (60/80 mesh) or equivalent.
6.4.3 Detector—Flame ionization detector.
This type of detector has proven effective in
the analysis of wastewaters for the param-
eters listed in the scope (Section 1.1). and
was used to develop the method performance
statements in Section 12. Guidelines for the
use of alternate detectors are provided in
Section 10.1.
5.5 Syringes—6-mL, glass hypodermic
with Luerlok tip (two each).
5.6 Micro syringes—26-fiL. 0.006 in. ID nee-
dle.
5.7 Syringe valve—2-way. with Luer ends
(three each).
5.8 Bottle—15-mL, screw-cap, with Teflon
cap liner. • '
5.9 Balance—Analytical, capable of accu-
rately weighing 0.0001 g.
6. Reagent*
6.1 Reagent water—Reagent water is de-
fined as a water in which an interferent is
not observed at the MDL of the parameters
of interest.
6.1.1 Reagent water can be generated by
passing tap water through a carbon filter bed
containing about 1 Ib of activated'carbon
(Filtrasorb-aoo. Calgon Corp.. or equivalent).
6.1.2 A water purification system
(Millipore 8nper-Q or equivalent) may be*
used to generate reagent water.
6.1.3 Regent water may also be prepared
by boiling, water for 15 min. Subsequently,
while maintaining the temperature at 90 *C.
bubble a contaminant-free inert gas through
. the water for 1 h. While still hot, transfer
the water to a narrow month screw-cap bot-
tle and seal with a Teflon-lined septum and
cap.
6.2 Sodium thiosulfate—(ACS) Granular.
6.3 Sodium hydroxide solution (10 N>—
Dissolve 40 g of NaOH (ACS) in reagent water
and dilute to 100 mL.
6.4 Hydrochloric acid (1+1)—Slowly, add
50 mL of concentrated HC1 (ACS) to 50 mL of
reagent water.
6.5 Trap Materials:
6.5.1 2,6-Diphenylene oxide polymer—
Tenaz (60/80 mesh), chromatographic grade
or equivalent.
&5£ Methyl silicons packing—3% OV-l on
Chromosorb-W (60/80 mesh) or equivalent.
674
-------
Environmental Protection Agency
PI. 13£, App. A, MeSh. 603
. 6.6 Stock standard solutions—Stock
standard solutions may be prepared from
pure standard materials or purchased as cer-
tified solutions. Prepare stock standard solu-
tions in reagent water using assayed liquids.
Since acrolein . and acrylonltrile are
lachrymatora, primary dilutions of these
compounds should be prepared in a hood. A
NIOSH/MESA approved toxic gas respirator
should be used when the analyst handles
high concentrations of such materials.
6.6.1 Place about 9.8 mL of reagent water
into a 10-mL ground glass stoppered volu-
metric flask.. For acrolein standards the rea-
gent water must be adjusted to pH 4 to 5.
Weight the flask to the nearest 0.1 mg.
6.64 Using a 100-pL syringe, immediately
add two or more drops of assayed reference
material to the flask, then reweigh. Be sure
that the drops fall directly into the water
without contacting the neck of the flask.
6.6^ Reweigh, dilute to volume, stopper.
then mix by inverting the flask several
, times. Calculate the concentration in |ig/|iL
from the net gain In weight. When compound
purity is assayed to be 98% or greater, the
weight can be used without correction to cal-
culate the concentration of the stock
staldard. Optionally, stock standard solu-
tions may be prepared using the pure stand-
ard material by volnmetrically measuring
the appropriate amounts and determining •
the weight of the material using the density
of the material. Commercially prepared
stock standards may be used at any con-
centration if they are • certified by the
Tnani^faft^^iT^f or by an Independent source.
6.6.4 Transfer the stock standard solution
into a Teflon-sealed screw-cap bottle. Store
at 4 *C and protect from light.
6.M Prepare fresh standards .daily;
6.7 Secondary dilution standards—Using
.stock standard solutions, prepare secondary
dilution standards in reagent water that con-
tain the compounds of interest, either singly
or mixed together. The secondary dilution
standards should be prepared at concentra-
tions such that the aqueous calibration
standards prepared in Section 7.3.1 or 7.4.1
will bracket the working range of the ana-
, lytical system. Secondary dilution standards
should be prepared daily and stored at 4 *C.
6.8. Quality control check sample con-
centrate-rSee Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that
meets the specifications in Section 5.2. Con-
dition the trap overnight at 180 *C by
backflushing with an inert gas flow of at
least 20 mlVmln. Condition the trap for 10
min once daily prior to use.
7.2 Connect the purge and trap system to
a gas chromatograph. The gas chro-
matograph must be operated using tempera-
ture and flow rate conditions equivalent to
those given in Table 1. Calibrate the purge
and trap-gas chromatographic system using
either the external standard technique (Sec-
tion 7.3) or the Internal standard technique '
(Section 7.4).
7.3 External standard calibration proce-
dure: . •
7.3.1 Prepare ' calibration standards at a
minimum of three concentration levels for
each parameter by carefully adding 20.0 |iL of
one or more secondary dilution standards to
100. 500. or 1000 mL of reagent water. A 25-»iL
syringe with a 0.006 in. ID needle should be
used for this operation. One of the external
standards should be at a concentration near, •
but above, the MDL and the other concentra-
tions should correspond to the expected
range of concentrations found in real sam-
ples or should define the, working range 'of
the detector. These standards must be pre-
pared fresh daily.
7.3J Analyze each .calibration standard
according to Section 10, and tabulate peak
height or area responses versus the con-
centration of the standard. The results can
be. used' to prepare a calibration curve for
each compound. Alternatively, if the ratio of
response to concentration (calibration fac-
tor) is a constant over the working range (<
10% relative standard deviation. BSD), lin-
earity through the origin can be assumed
and the average ratio or calibration factor
can be used in place of a calibration curve.
7.4 Internal standard calibration proce-
dure—To use this approach, the analyst must.
select one or more internal standards that
are similar In analytical behavior to the
compounds of interest. The analyst must fur-
ther demonstrate that the measurement of
the internal standard is not affected by
method or matrix Interferences. Because of
these limitations, no internal standard can
be suggested that is applicable to all sam-
ples.
7.4.1 Prepare calibration standards at a
of three concentration levels for
each parameter of interest as described in
Section 7.3.1.
7.4JI Prepare a spiking solution contain-
ing each of the Internal standards using the
procedures described in Sections 6.6 and 6.7.
It is recommended that the secondary dilu-
tion standard be prepared at a concentration
of 15 iig/mL of each internal standard
compound. The addition of 10 |iL of this
standard to 5.0 mL of sample or calibration
standard would be equivalent to 30 |ig/L.
7.4.3 Analyze each calibration standard
according to Section 10. adding 10 pL of in-
ternal standard spiking solution directly to
the syringe (Section 10.4). Tabulate peak
height or area responses against concentra-
tion for each compound and internal stand-
ard. and calculate response factors (RF)'for
each compound using Equation 1.
675
-------
fT. loo, App. /%. m«m. owo
V»TK
I \/— I— »
BF*
(AtaXC.)
Equation 1
where:
A««Besponse for the parameter to be meas-
ured.
Afc»Besponse for the Internal standard.
Ck»Ccnoentration of the Internal standard.
^•Concentration of the parameter to be
measured.
If the BP value over the working range IB a
constant <<10% BSD), the BF can be assumed
to be invariant and the average BF can be
used for calculations. Alternatively, the re-
sults can be used to plot a calibration curve
of response ratios, AJA*. vs. BF.
7.5 The working calibration curve, cali-
bration factor, or BF must be verified on
eaoh working day by the measurement of a
QC check sample.
7.5.1 .Prepare the QC check sample aa de-
scribed in Section BJU2.
• 7JL2 Analyse the QC check sample accord-
ing to Section 10.
7.&S For each parameter, compare the re-
sponse (Q) with the corresponding calibra-
tion acceptance criteria found in Table 2. If
the responses for all parameters of interest
fall within the designated ranges, analyslB of
actual samples can begin. If any individual Q
falls outside the range, a new calibration
curve, calibration factor, or BF must be pre-
pared for that parameter according to Sec-
tion 7.3 or 7.4. .
8. Quality Control
8.1 Each laboratory that uses this method
is required to operate a formal Quality con-
trol program. The "M"1"mm reqnlremente of
program consist of an <«<*t«i demonstra-
tion of laboratory capability and an ongoing
analysis of spiked samples to evaluate and
document data quality. The laboratory must
maintain records to document the quality of
data that is generated. Ongoing data quality
checks are compared with established, per-
formance criteria to determine if the results
of analyses meet the performance character-
istics of the method. When results of sample
spikes indicate atypical method perform-
ance, a quality control check standard must
be analysed to confirm that the measure-
ments were performed in an in-control mode
of operation.
8.1.1 The analyst must make an initial.
one-time, demonstration of the ability to
generate acceptable accuracy and precision
with this method. This ability is established
as described in Section &2.
8.1.2 In recognition of advances that are
occurring in chromatography, the analyst Is
permitted certain options (detailed in Sec-
tion UU) to improve the separations or lower
the dost of measurements. Bach time such a
modification is made to the method, the ana-
lyst is required to repeat the procedure in
Section 8JL
8.1.3 Each day. the analyst must analyse a
reagent water blank to demonstrate that
Interferences from the analytical system are
under control.
8.1.4 The laboratory must, on an ongoing
basis, spike and analyze a tniHim^Tn of 10%
of all samples to monitor and evaluate lab-
oratory data quality. This procedure is de-
scribed in Section 8£.
8.1.6 The laboratory must, on an ongoing
basis, demonstrate through the analyses of
quallt/y control check standards that the op-
eration of the measurement system is in con-
trol. This procedure is described in Section
8.4. The frequency of the check standard
analyses is equivalent to 10% of all samples
analyzed but may be reduced if spike recov-
eries from samples (Section 8.3) meet all
specified quality control criteria.
8.1.6 The laboratory must maintain per-
formance records to document the quality of
data that is generated. This procedure is de-
scribed in Section 8U>.
8.2 To establish the ability to generate
acceptable accuracy and precision, the ana-
lyst must perform the following operations.
8.2.1 A quality control (QC) check sample
concentrate is required containing each pa-
rameter of interest at a concentration of 25
lig/mL in reagent water. The QC check sam-
ple concentrate must be obtained from the
U.S. Environmental Protection Agency. En-
vironmental Monitoring and Support Lab-
oratory in Cincinnati. Ohio, if available. If
not available from that source. tLe QC check
sample concentrate must be obtained from
another external source. If not available
from either source above, the QC check sam-
ple concentrate must be prepared by the lab-
oratory using stock standards prepared inde-
pendently from those used for calibration.
8JL2 Prepare a QC check sample to con-
tain 50 |ig/L of eaoh parameter by adding 200
|il> of QC check sample concentrate to 100 mL
of reagent water.
8&3 Analyze four 6-mLi aliqnots of the
well-mixed QC check sample according to
Section 10. .
8.2.4 Calculate the average recovery (X) in
pg/L, and the standard deviation of the re-
covery (8) in pg/L. for each parameter using
the four results. .
8.2.5 For each parameter compare s and X
with .the corresponding acceptance criteria
for precision and accuracy, respectively.
found in Table 3. If s and X for all param-
eters of Interest meet the acceptance cri-
teria, the system performance is acceptable
and analysis of actual samples can begin. If
either s exceeds the precision limit or X falls
outside th? range for accuracy, the system
performance is unacceptable for that param-
.676
-------
Environmental PiotedtonAgancy
eter. locate and correct the source of the
problem' and repeat the test for each
compound of interest.
8.3 The laboratory mast, on an ongoing
basis, spike at least 10% of the samples from
each sample site being monitored to assess
accuracy. For laboratories analysing one to
ten samples per month, at least one spiked
sample per month is required.
8.3.1 The concentration of the spike in the
sample should be determined as follows:
8.3.1.1 If, as in compliance monitoring,
the concentration of a specific parameter in
the sample is being checked against a regu-
latory concentration limit, the spike should
be at that limit or 1 to 5 times higher than
the background concentration determined in
Section 8^2, whichever concentration would
be larger.
8.3.1.2 If the concentration of a specific
parameter in the sample Is not being
checked against a limit specific to that pa-
rameter, the spike should be at 50 |ig/L or 1
to 6 times higher than the background con-
centration determined in Section 8.3.2,
whichever concentration would be larger.
8.&2 Analyse one S-mL sample aliquot to
determine the background concentration (B)
of each parameter. If necessary, prepare a
new QC check sample concentrate (Section
8JZ.1) appropriate for the background con-
centrations in the sample. Spike a second 6-
mL sample aliquot with 10 pL of the QC
check sample concentrate and analyse it to
determine the concentration after spiking
(A) of each parameter. Calculate each per-
cent recovery (P) as 100(A-B)%/T. where T is
the known true value of the spike.
8A3 Compare the percent recovery (P) for
each parameter with the corresponding QC
acceptance criteria found in Table 3. These
acceptance criteria were calculated to In-
clude an allowance for error in measurement
of both the background and spike concentra-
tions, assuming a spike to background ratio
of 5:1. This error will be accounted for to the
extent that the analyst's spike to back-
ground ratio approaches 5:1.'
8.3.4 If any individual P falls outside the
designated range for recovery, that param-
eter has failed the acceptance criteria. A
check standard, containing each parameter
that failed the criteria must be analyzed as
described in Section 8.4.
8.4 If any parameter fails the acceptance
criteria for recovery in Section 8.3, a QC
check standard containing each parameter
that failed must be. prepared and analyzed.
NOTE: The frequency for the required anal-
ysis of a QC check standard will depend upon
the number of parameters being simulta-
neously tested, the complexity of the sample
matrix, and the performance of the labora-
tory.
8.4.1 Prepare the QC check standard by
adding 10 pL of QC check sample concentrate
PI. 136. App. A, MaSh. 603
(Section 8.2J or 8.3.2) to 5 mL of reagent
water. The QC cheek standard needs only to
contain the parameters that failed criteria
in the test in Section 8.3.
8.4.2 Analyze the QC check standard to
determine the concentration measured (A) of
each parameter. Calculate each percent re-
covery (P.) as 100 (A/T)%. where T is the true
value of the standard concentration.
8.4.3 Compare the percent recovery (P.)
for-each parameter with the corresponding
QC acceptance criteria found in Table 3. Only
parameters that failed the test in Section 8.3
need to be compared with thesa criteria. If
the recovery of any such pBrametgr falls out-
side the designated range, the laboratory
performance for that parameter is judged to
be out of control, and the problem must be
immediately identified and corrected. The
analytical result for that parameter in the
unspiked sample is suspect and may not be
reported for regulatory compliance purposes.
8J> As port of the QC program for the lab-
oratory, method accuracy for wastewater
samples must be assessed and records must
be maintained. After the analysis of five
spiked wastewater samples as in Section 8.3.
calculate the average percent recovery (P)
and the standard deviation of the percent re-
covery (8,). Express the accuracy assessment
as a percent recovery interval from P-2s. to
P+28p. If P=90% and v=10%, for example, the
accuracy interval is expressed as 70-110%.
Update the accuracy assessment for each pa-
rameter on a regular basis (e.g. after each
five to ten new accuracy measurements).
, 8.6 It is recommended that the laboratory
adopt additional quality assurance practices
for use with this method. The specific prac-
tices that are most productive depend upon
the needs of the laboratory and the nature of
the samples. Field duplicates may be ana-
lysed to assess the precision of the environ-
mental measurements. When doubt exists
over the identification of a peak on the chro-
matogram. confirmatory techniques such as
gas ohromatography with a dissteaUiiT col-
umn or'mass spectrometer must be used.
Whenever possible, .the laboratory should
analyze standard reference materials and
participate in relevant performance evalua-
tion studies.
9. Sample Collection, Preservation, and
Handling
9.1 All samples must be iced or refrig-
erated from the time of collection until anal-
ysis. If the sample contains free or combined
chlorine, add sodium thiosulfate preserva-
tive (10 mg/40 mL is sufficient for up to 5
ppm Cla) to the empty sample bottle just
prior to shipping to the sampling site. EPA
Methods 330.4 and 330.5 may be used for
measurement of residual chlorine.* Field test
kits are available for this .purpose. .
9.2 If acrolein is to be analyzed, collect
about 500 mL of sample in a clean glass con-
677
-------
H. 156, App. A, Mwm. ou*
tainer. Adjust the pH of the sample to 4_to6
using add or base, measuring with narrow
range pH paper. Samples for acroleln analy-
sis receiving no pH adjustment most be ana*
lysed within 3 days of sampling. . .
. 8J Grab samples aunt be collected la
ft^tf containers having a total volume of at
least 25 mL. Fill the sample bottle jost to
overflowing in each a manner that no air
bobbles pass through the sample as the bot-
tle is h^tif filled. Seal the bottle so that no
air babbles are entrapped in It. If preserva-
tive has been added, shake vigorously for 1
min. u« parameters in the sam-
ple by comparing the retention times of the
peaks in the sample chromatogranv with
those of the peaks in standard
chromatograms. The width of the retention
time window used to make identifications
should be based upon measurements of ac-
tual retention time variations of standards
over the course of a day. Three times the
standard deviation of a retention time for a
compound can be used to calculate a sug-
gested window size; however, the experience
of the analyst should weigh heavily in the
interpretation of chromatograms.
H* QrffMffltfffTty
11.1 Determine the concentration of indi-
vidual compounds in the sample.
11.1.1 If the external standard calibration
procedure Is used, calculate the conoentra--
tton of the parameter being measured from
the peak response using the calibration
curve or calibration factor determined In
Section 7^2.
11.1.2 If the internal standard calibration
procedure is used, calculate the concentra-
tion in the sample using the response factor
(RF) determined in Section 7.4:3 and Equa-
tion 2.
(A.XC,.)
Concentration. (pg/L)
Equation 2
where:
A.=Response for the parameter to be meas-
ured..
AtrtResponse for the Internal standard.
CfcsConcentration of the internal standard.
11.2 Report results in |ig/L without correc-
tion for recovery data. All QC data obtained
should be reported with the sample results.
12. Method Performance
12,1 The method detection limit (HDL) is
defined as the TTt*tl
-------
with 99% oonfldenoe that the value is above
sero.' The MDL concentrations listed in
Table 1 were obtained using reagent water.*
The MDL actually achieved in a given analy-
sis will vary depending* on instrument sen-
tltivity and matrix effects.
12,8 This method is recommended for the
concentration range from the MDL to
l.OOOxMDL. Direct aqueous injection tech-
niques should be used to measure concentra-
tion levels above 1.000xMDL.
123 In a single laboratory (Battelle-Co-
lumbns). the average recoveries and standard
deviations presented in Table 2 were ob-
tained.* Seven replicate samples were ana-
lyzed at each spike level.
References
1.40 CFR part 136. appendix B.
2. Bellar. TJU and Llchtenberg. J.J. "De-
termining Volatile Organics at Microgram-
per-Litre-Levels by Gas Chromatography."
Journal American Water Work* Association. 66,
79(1974).
3. "Evaluate Test Procedures for Acrolein
and Acrylonitrlle." Special letter report for
EPA Project 4719-A, U.S. Environmental
Protection Agency. Environmental Monitor-
ing and Support Laboratory. Cincinnati.
Ohio 45268.27 June 1979.
4. "Carcinogens—Working With Carcino-
gens," Department of Health. Education, and
Welfare. Public Health Service. Center for
Disease Control. National Institute for Occu-
pational Safety and Health. Publication No.
77-206. August 1977.
6. "OSHA Safety and Health Standards.
General Industry." (29 CFR part 1910). Occn-
Pt.l36.App.A.lliEti.40l
national Safety and Health
OSHA 2206 (Revised, January 1976).
6. "Safety in Academic Chemlstey Labora-
tories," American Chemical Society Publica-
tion. Committee on Chemical Safety. 3rd
Edition. 1979.
7. Provost, LJP., and Elder. R.8. "Ihterpra-
tation of Percent Recovery Data." American
Laboratory. 15.56-63 (1963).
8. "Methods 330.4 (Titdmetric. DPD-PAS)
and 330^6 (Spectrophotometrie. DPD) for
Chlorine. Total Residual." Methods for
Chemical Analysis of Water and Wastes.
EPA-600/4-79-020. U.S. Environmental Pro-
tection Agency. Environmental Monitoring
and Support Laboratory. Cincinnati. Ohio
45268. March 1979.
9. "Evaluation of Method 603 (Modified)."
EPA-800/4-84-ABC, National Technical Infor-
mation Service. PB84-. Springfield. Virginia
•22161. Nov. 1984.
TABLE 1—CHROMATOQBAPWC CONDITIONS AND
METHOD DETECTION LIMITS
. ID tfns or «^rJcu «te3l cotam
tt 40 rS/mii tow nts. Cokmn t-
miri * WC ta -4 n. ttwpBWBB
120% and Mid lor 12 mm.
TABLE 2—SINGLE LABORATORY ACCURACY AND PRECISION—METHOD 603
,*— . /;. •
'i
Arnil/wwtrfln -----
*uy***uwn •!•••• ... •••••!•
a?
RW
RW
POTW
POTW
IW
IW
RW
RW
POTW
POTW
IW
IW
Spto
cone.
(DOV
SJO
900
&0
SOJO
&0
100D
. &0
60JO
20.0
100A
10.0
100A
AMHO*
raoowy
(M»4
&2
6M
4J)
444
ai
94
42
51.4
20.1
1014
9.1
104.0
8ter«i^
dv^c^sn
(HOAJ
02
0.7
O2
04
0.1
1.1
02
14
04
14
04
32
pw^jl
moownr
104
103
80
89
2
9
64
103
100
101
91
104
APOTW-Prachtorination Mcondny afBuant from •
AMMnduttial oaHanratar eontainlno an urtidanaiad «
•mnoa MXmant plant
679
-------
TABLE 3-CAuenATioN AND QCACCEPTANCE Lx-A£n£M«^farfeur^^
CRITERIA—METHOD 603* p. p^.pwo«rt' memory iMMirad (SwUon 933. SacHon
8A2). •
AcroWn —
AaytonMhi.
Rang* tor
4&0-64.1
tor 8
V
9.9
Rngilar
42^-60.1
33.1-46LB
88-118
71-135
•*CriMrta wm ealculiUfl aMutntag • QC ctaek aampto
conewMllon o( 60 O0fL.*
nMMind In QC dwek swnpte. in
680
-------
Envtranmontal Protection Agoney
Pfc 136. App. A, MoJJx
OPTIONAL
FOAM
TRAP
Vi IN.
0. D. EXIT
EXIT '/« IN.
0. D.
—14MM 0. D.
INLET % IN.
0. D.
SAMPLE INLET
2-WAY SYRINGE VALVE
17CM. 20 GAUGE SYRINGE NEEDLE
. 0. D. RUBBER SEPTUM
~10MM. 0. D.
INLET
IN. 0. D.
1/16IN.O.D.
\/ STAINLESS STEEL
13X MOLECULAR
SIEVE PURGE
GAS FILTER
10MM GLASS FRIT
MEDIUM POROSITY
PURGE GA§
ROW
CONTROL
{Figure 1. Purging device
681
-------
it. too, App. A, Mem. ooo
PACKING PROCEDURE
GLASS
WOOL
TENAX 23CM
Z% OV-1
GLASS WOOL
1CM
TRAP INLET
... . ~ 4UUNtGn.il/-i-ydtaiiion)
CONSTRUCTION
. COMPRESSION FITTING
^ NUT AND FERRULES
14FT.71/FOOT RESISTANCE
'WIRE WRAPPED SOLID
THERMOCOUPLE/
CONTROLLER
SENSOR
aECTRONIC
TEMPERATURE
CONTROL
AND
I PYROMETER
CJ~C "•/ TUBING 25CM.
0.105 IN. I.D.
0.125 IN. O.D.
STAINLESS STEEL
Figure 2. Trap packings and construction to include
. desorb capability.
682
-------
tiivhumoentcri Proiectton Agency
1SXMOUCUUM
ft. 136, App. A. Mcfh. 403
oe INJECTION
roar
. KfftOI
now
CONTMOtLaN
Figure 3. Purge and trap system-purge mode.
1W MOLECULAR
MCVE MLTER •
QC INJCCnOM
MMT
COUNTM-
CLOCKWISE
ROTATION
TRAP
MATED
WATCH BATH
Figure 4. Purge and trap system-desorb mode.
-------
Pt. 136, App. A, Moth. 603
40 CFR Ch. I (7-1-95 EdWon)
Column: Porapak-QS
.Program: T10°C for 1.5 min, rapidly
heated to 150°C
Detector: Fiame lohization
1.5 .3.0 4.5 6.0 7.5 g.O ^ 10.5 12.0 13.5 15.0
RETENTION TIME. MIN. '
Figure 5. Gas chromatogram of acrolein and ecrylonitrile.
684
-------
Environmental Protection Agency
Pt. 136, App. A, M&fh.
METHOD 604—PHENOLS
/. Scope and Application
' 1.1 This method covers the determination
of phenol and certain substituted phenols.
The following parameters may be deter-
mined by this method:
2—CtiloraptMnol.
2-MathyMfrdtoltTOphqool
4+fOmatmnt*
PMMMoroplMnol
2.4.6-TriotUorophenol
STORE!
No.
34462
34586
34601
34606
34616
34657
34501
34646
39032
34684
34621
CAS No.
59-60-7
95-67-8
120-83-2
105-67-8
51-28-6
534-62-1
88-76-6
100-02-7
87-96-6
108-86-2
BB-08-2
1.2 This is a flame ionization detector gas
chromatographic (FIDOC) method applicable
to the determination of the compounds listed
above in municipal and industrial discharges
as provided under 40 CFR 136.1. When this
method is used to analyze gtifcTrnnm* sam-
ples for any or all of the compounds above.
compound identifications should be sup-
ported by at least one additional qualitative
technique. This method describes analytical
conditions for derivatization. cleanup, and
electron capture detector gas chroma-
tography (ECDQC) that can be used to con-
firm innMiii BinniiliH tntyfli* by FIDGC. Method
625 provides gas chromatograph/mass spec-
trometer (GC/MS) conditions appropriate for
the qualitative and quantitative confirma-
tion of results for all of the parameters list-
ed above, using the extract produced by this
method.
1.3 The method detection limit (MDL, de-
fined in Section 14.1) * for each parameter is
listed in Table 1. The MDL for a specific
wastewater may differ from those listed, de-
pending upon the nature of interferences in
the sample matrix. The MDL listed in Table
1 for each parameter was achieved with a
flame ionization detector (FID). The MDLs
that were achieved when the derivatization
cleanup and electron capture detector (BCD)
were employed are presented in Table 2.
1.4 Any modification of this method, be-
yond those expressly permitted, shall be con-
sidered as a major modification subject to
application and approval of alternate test
procedures under 40 CFR 136.4 and 136.5.
1.5 This method is restricted to use by or
under the supervision of analysts experi-
enced in the use of a gas chromatograph and
in the interpretation of gas chromatograms.
Bach analyst must demonstrate the ability
to generate acceptable results with this
method using the procedure described in Seo-
tton&JL
2. Summary of Method
2.1 A measured volume of sample, ap- •
•proximately 1-L, is acidified and extracted
with methylene chloride using a separator?
funnel..The methylene chloride extract is
dried and exchanged to 2-propanol during
concentration to a volume of 10 roL or less.
The extract is separated by gas chroma-
tography and the phenols are then measured
with an FID.2 ,
2.2 A • preliminary sample wash under
basic conditions can be employed for samples
having high general organic and organic base
interferences.
• 2.3 The method also provides for a
derivatization and column chromatography
cleanup procedure to aid in the elimination
of interferences." The derivatives are ana-
lyzed by ECDGC.
3. Interferences
3.1 Method interferences may be. caused
by contaminants in solvents, reagents, glass-
ware, and other sample procegsisg hardware
that lead to discrete artifacts and/or ele-
vated baselines in gas chromatograms. All of
these materials must be routinely dem-
onstrated to be free from interferences under
the conditions of the analysis by running
laboratory reagent blanks as described in
Section 8.1.3.
3J.I Glassware must be scrupulously
cleaned.4 Clean all glassware as soon as pos-
. sible after use by rinsing with the last sol-
vent used in it. Solvent rinsing should be fol-
lowed by detergent waaMtss with hot water.
and rinses with tap water and distilled
water. The glassware should then be drained
dry. and heated in a muffle furnace at 400 *C
for 15 to 30 min. Some thermally stable ma-
terials, such as PCBs, may not be eliminated
by this treatment. Solvent rinses with ace-
tone and pesticide quality hexane may be
substituted for the muffle furnace heating.
Thorough rinsing with such solvents usually
ftHmiT^f.M PCB interference. Volumetric
ware should not be heated in a muffle fur-
nace. After drying and cooling, glassware
should be sealed and stored in a clean envi-
ronment to prevent any accumulation of
dust or other contaminants. Store inverted
or capped with aluminum foil.
3J..2 The use of high purity reagents and
solvents helps to minimiM interference prob-
lems. Purification of solvents by distillation
in all-glass systems may be required.
3.2 Matrix interferences may be caused by
contaminants that are coextracted from the
sample. The extent of matrix interferences
will vary considerably from source to source.
depending upon the nature and diversity of
the industrial complex or municipality being
sampled. The derivatimtion cleanup proce-
dure in Section 12 can be used to overcome
many of these interferences, but unique sam-
ples r"*y require additional cleanup ap-
685
-------
n. too, Mpp. M, mem. ou*»
preaches to achieve the MDL listed In Tables
land 2.
3.3 The basic sample wash (Section 10.2)
may cause significantly reduced recovery of
phenol and 2,4-dimethylphenol. The analyst
must recognize that results obtained under
these conditions are minimum • concentra-
tions.
4. Safety
4.1 The tozicity or carcinogenicity of
each reagent used in this method has not
been precisely defined; however, each chemi-
cal compound should be treated as a poten-
tial health hazard. From this viewpoint, ex-
posure to these chemicals must be reduced to
the lowest possible level by whatever means
available. The laboratory is responsible for
maintaining a current awareness file of
OSHA regulations regarding the safe han-
dling1 of the chemicals specified in this meth-
od. A reference file of material data
sheet* should also, be made available to all
personnel involved in the chemical analysis.
Additional references to laboratory safety
are available and have been identified*-7 for
the Information of analyst.
4*2 Special care should be taken in han-
dling pentaflnorobenzyl bromide, which is a
lachrymator, and 18-crown-6-ether. which is
hiffhly toxic.
5. Apparatus and Materials
6.1 Sampling equipment, for discrete or
composite sampling.
5.1.1 Grab sample bottle— 1-L or 1-qt.
amber glass, fitted with a screw cap lined
with Teflon. Foil may be substituted for Tef-
lon if the sample is not corrosive. If amber
bottles are not available, protect samples
from light. The bottle and cap liner must be '
washed, rinsed with acetone or methylene
chloride, and dried before use to minimim
contamination.
5.1.2 Automatic sampler (optional)— The
sampler must Incorporate glass sample con-
tainers for the collection of a minimum of
250 ml* of sample. Sample containers must be
kept refrigerated at 4*C and protected from
light during compositing. If the sampler uses
a peristaltic pump, a minimum length of
compressible silicons rubber tubing may be
used. Before use. however, the compressible
tubing should be thoroughly rinsed with
methanol, followed by repeated rinsings with
distilled water to minimize the potential for
contamination of the sample. An integrating
flow meter is required to collect flow propor-
tional composites.
5.2 Glassware (All specifications, are sug-
gested. Catalog numbers are included for 11-
•Instratlon only.):
5.2.1 Separately funnel— 2-L, with Teflon
stopcock.
5.2.2 Drying column—Chromatographic
column. 400 mm long x 19 mm ID. with
coarse frit filter disc.
5.2.3 Chromatographic column—100 .mm
long x 10 mm ID, with Teflon stopcock.
5.2.4 Concentrator tube. Kpderna-Dan-
ish—10-mL. graduated (Kontes K-570050-1025
or equivalent). Calibration must be checked
at the volumes employed in the test. Ground
glass stopper is used to prevent evaporation
of extracts.
5.2.5 Evaporative flask. Kudema-Danish—
500-mL (Kontes K-570001-0500 or equivalent).
Attach to •concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danlsh—
Three-ball macro (Kontes K-503000-0121 or
equivalent).
5.2.7 Snyder column. Kuderna-Danlsh—
Two-ball micro (Kontes K-569001-0219 or
equivalent). ' . •. '
5.2.8 Vials—10 to 15-xnL. amber glass, with
Teflon-lined screw cap.
5.2.9 Reaction flask—15 to 25-mL round
bottom flask, with standard tapered joint.
fitted with a water-cooled condenser and U-
shaped drying tube containing granular cal-
cium chloride.
5.3 Boiling chips—Approximately 10/40
mesh. Heat to 400 *C for 30 min or Soxhlet ex-
tract with methylene chloride.
5.4 Water bath—Heated, with concentric
ring cover, capable of temperature control
(±2*C). The bath should be used in a hood.
5.5 Balance—Analytical, capable of accu-
rately weighting 0.0001 g.
5.6 Gas chromatograph—An analytical
system complete with a temperature pro-
grammable gas chromatograph suitable for
on-column injection and all required acces-
sories including syringes, analytical col-
umns, gases, detector, and strip-chart re-
corder. A data system is recommended for
measuring peak areas.
5.6.1 Column for underlvatized phenols—
1.8 m long x 2 mm n> glass, packed with 1%
8P-1240DA on Supelcoport (80/100 mesh) or
equivalent. This column was used to develop
the method performance statements In Sec-
tion 14. Guidelines for the use of alternate
column packings are provided in Section
11.1.
5.6.2 Column for derivatized phenols—1.8
m long x 2 mm ID glass, packed with 5% OV-
17 on Chromosorb W-AW-DMCS (80/100 mesh)
or equivalent. This column has proven effec-
tive in the analysis of wastewaters for
derlvatization products of the parameters
listed in the scope (Section 1.1), and was used
to develop the method performance state-
ments in Section 14. Guidelines for the use of
alternate column packings are provided in
Section 11.1.
5.6.3 Detectors—Flame ionlzatipn and
electron capture detectors. .The FID is used
when determining the parent phenols. The
BCD is used when determining .the
derivatized phenols. Guidelines for the use of
686
-------
PI. 136. App. A. lfa$L 604
alternatve detectors are provided in Section
ILL • •'-.-.- • -. - '.- '•
t. Reagents
64 Reagent water-Reagent water is de-
fined as a water in which an iaterferent is
not observed at the HDL of the parameters
of interest.
62 8odi«™ hydroxide solution (10 N)—
Dissolve 40 g of NaOH (ACS) in reagent water
and dilute to 100 mL.
6A Sodium hydroxide solution (1 N)—Dis-
solve 4 g of MaOH (ACS) in reagent water and
dilute to 100 mL.
6.4 Sodium snlfate—(ACS) Granular, an-
hydrous. Purify by heating at 400*C for 4 h in
a shallow tray.
64 Sodium thlosnlfate--81owly, add 58 mL
of HaSO* (ACS. sp. gr. L84) to reagent water
and dilute to 1L.
64 Potassium carbonate—(ACS) Pow-
dered.
&9 Pentafluorobensyl bromide (a-
Bromopentafluorotolnene)-47% minimum
purity.
NOTE This chemical is a laehrymator. (See
Section 13.)°
640 16-crown-€-ether (1.4.740.1346-
rolobctadeoane)—fl8% Tnlnlmum
al
Store at 4 *C 'and protect firam MeW. stock
standard solutions should be ohssktd fre-
quently for signs of degradftttem or evapo-
ration. especially just prior to preparing
calibration standards from then. .
644£ Stock standard soluttoas must be
replaced after six monthy. or *ooa«r if com-
parison with check 'standards indi@a.te* a
problem.
646 Quality control chMk sample con-
centrate— See Section 8.24.
7. CaUbmttm
74 To calibrate the FESOC for the
anaylsls 'of underivatlsed phenoia, establish
gas chromatographic operating conditions
equivalent to those given in Table 1. The gas
chromatographic system can be calibrated
n«i«y the external standard technique (Sec-
tion 7.2) or the internal staMssd tec*w«iane
(SeottonTJ). ^_
7^ External standard caUbratiOB proce-
dure for FIDOC:
Prepare calibration staaStfds at a
of three concentrattoa levels for
parity.
MOTBI Thi
641 Derivatt
toxic.
tion reagent-*-Add 1 mL of
.pentaflnorobensyl bromide and 1 g of 18-
crown-6-ether to a 50-mL volumetric flask
and dilute to volume with 2-propanol. Pre-
pare fresh weekly. This operation should be
carried out in a hood. Store at 4 *C and pro-
tect from light.
642 Acetone, hexane. Tn^t3*"*"*, methyl-
ene chloride. 2-propanol. toluene— Pesticide
quality or equivalent. .
643 Silica gel— 100/200 mesh. Davlson.
grade-flOS or equivalent. Activate at 130 *C
overnight and store in a desiccator.
644 Stock standard solutions (1.00 |tg/
liL)— Stock standard solutions may be pre-
pared from pure standard matmrlalH or pur-
chased as certified solutions.
6444 Prepare stock standard solutions -by
accurately weighing about 0.0100 g of pure
material. Dissolve the material in 2-propanol
and dilute to volume in a 10-mL volumetric
flask. Larger volumes can be used at the con-
venience of the analyst. When compound pu-
rity is assayed to be 96% or greater, the
weight can be used without correction to cal-
culate the concentration of the stock stand-
ard. Commercially prepared stock standards
can be used at any concentration if they are
certified by tfr* TTi*iTii7fa"*T>1i'«>f' or by an inde-
pendent source:
644£ Transfer the stock standard solu-
tions into Teflon-sealed screw-cap bottles,
each parameter of interest by adding- vol-
umes of one or more stock sta&AMds to a
volumetric flask and diluting to volume with
2-propanol. One of the extesaal standards
should be at a concentration near, but above.
the MDL (Table 1) and the other concentra-
tions should correspond to the expected
range of concentrations found in real sam-
ples or should define the working range of
^jfo«y QOtOOtOF*
7JL2 Using injections of 2 to 6 |il. analyse
each calibration standard according to Sec-
tion 11 and tabulate peak height or area re-
sponses against the mass injected. The re-
sults can be used to prepare a calibration
curve for each compound. Alternatively, if
the ratio of response to amount injected
(calibration factor) is a oomstsst^ovp the
working range (<10% relative standard devi-
ation, BSD), linearity through the origin can
be assumed and the average ratio or calibra-
tion factor can be used in plaee of a calibra-
tion curve.
7.3 Internal standard calibration proce-
dure for FIDOO—To use this approach, the
analyst must select one or more internal
standards that are similar in analytical be-
havior to the compounds of interest. The an-
alyst must further demonstrate that the
measurement of the internal standard is not
affected by method or matrix interferences.
Because of these limitations, no internal
standard can be suggested that is applicable
to all samples. - . _. ' -
7.34 Prepare calibration standards at a
of three concentration levels for
each parameter of interest by adding vol-
umes of one or more stock staa«asds to a
volumetric flask. To «*ch calibration stand-
ard. add a known constant amount of one or
more internal Btisn^«»^«, and dilute to vol-
ume with 2-propanoL One of the steadsxdft
687
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should be at a oonoentration near, but above,
the MDL and the other concentrations
should correspond to the expected range of
oonoentxations found in real samples or
should define the working range of the detec-
tor.
7A2 Using injections of 2 to 5 |ili. analyse
each calibration standard according to Sec-
tion 11 and tabulate peak height or area re-
sponses against concentration for each
compound and internal standard. Calculate
response factors (BF) for each compound
using liquation 1.
RF*
(A.XC».)
(A4.XC.)
Equation 1
where:
A.*Besponse for the parameter to be meas-
ured.
Ak»Besponse for the Internal standard.
d^Conoentration of the Internal standard
(^•Concentration of the parameter to be
measured (pg/L).
If the BF value over the working range is
a constant (<10% BSD), the BF can be as-
sumed to be invariant and the average BF
can be used for calculations. Alternatively,
the results can be used to plot a calibration
curve of response ratios. AJAb, vs. BF.
7.4 The working calibration curve, cali-
bration factor, or .BF must be verified on
each working day by the measurement of one
or more calibration standards. If the re-
sponse for any parameter varies from the
predicted response by more than ±15%. a new
calibration curve must be prepared for that
compound.
7.6 To calibrate the ECDOC for the analy-
sis of phenol derivatives, establish gas
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