particulate matter removed in the rinse of the train probe and nozzle. Add the

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7.3.4.6
Concentrate the sample in Container 4 (acetone/methylene chloride
rinses) to a volume of about 1 - 2 mL using a Kuderna-Danish concentrator apparatus,
followed by nitrogen evaporation at a less than 37
EC. Rinse the sample container three
times with small portions of methylene chloride and add these to the concentrated
solution and concentrate further to near dryness. Add the concentrate to the XAD-2®
resin in the Soxhlet apparatus described above.
7.3.4.7
Add 40 µL of the internal standard solution. Fortification is
accomplished by using the sample fortification solutions described in Table 1. Cover the
contents of the extraction thimble with a cleaned glass wool plug to prevent the XAD-2®
resin from floating into the solvent reservoir of the extractor and proceed with extraction
(Sec. 7.3.2).
7.3.5
Sample extraction - Place the thimble in the extractor and add the toluene
contained in the beaker to the solvent reservoir. Pour additional toluene to fill the reservoir
approximately two-thirds full. Add Teflon® boiling chips and assemble the apparatus. Adjust
the heat source to cause the extractor to cycle three times per hour. Extract the sample for
16 hours. After extraction, allow the Soxhlet to cool. Transfer the toluene extract and three 10-
mL between rinses to the rotary evaporator. Concentrate the extract to approximately 10 mL.
Use a nitrogen evaporative concentrator to reduce the volume of the extract to about
100 µL. Redissolve the residue in 5 mL of hexane.
7.3.6
Sample clean-up and fractionation - Sample extracts described above are spiked
with 40 µL of the alternate standard fortification solution, then divided into two equal portions.
One half of each sample extract is archived for future needs. The other portion is solvent-
exchanged to hexane then subjected to three column chromatographic cleanup steps as
described in Method 8290.
7.3.7
Analysis summary - The samples are analyzed with a high resolution gas
chromatographic column coupled to a high resolution mass spectrometer (HRGC/HRMS) using
the instrumental parameters described below. Prior to analysis, the Recovery Standard
solution from Table 1 is added to each sample. Sample extracts are first analyzed using a
capillary column to determine the concentration of each isomer of PCDDs and PCDFs (tetra-
through octa-). If 2,3,7,8-TCDF is detected in this analysis, another aliquot of the sample is
analyzed separately, using a second, dissimilar column to confirm and more accurately
measure the 2,3,7,8-TCDF isomer. Other column systems may be used, provided that the
user is able to demonstrate by means of calibration and performance checks that the column
system is able to meet the specifications of Method 8290.
7.3.8
All other analytical specifications for determining the amounts of PCDD/PCDF
isomers collected in the filter/front half and sorbent trap/back half fractions can be found in
Method 8290.
7.4
Calculations
The mass of each isomer from the front half train fraction is added to that from the back half
fraction to obtain a train total before further calculation. If a measurable amount of the isomer is
found in one fraction, but the amount in the second fraction is below detection limit, the following
strategy is recommended, but is subject to being overruled by regulatory authorities. Count the
"nondetect" as zero if the detection limit is less than 10% of the total of the detected amount from
the other fraction. In cases where the detection limit in the second fraction is greater than 10% of

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the amount detected in the first fraction, then report the total as greater than the detected amount
but less than the detected amount plus the second fraction detection limit.
The following section describes the calculations used to determine gas concentrations and
emissions of PCDD and PCDF isomers. Toxic equivalent calculations are not included in this
method. Each set of calculations should be repeated or spot-checked, as a QC measure.
Calculations should be carried out to at least one extra decimal place beyond that of the acquired
data and should be rounded off after final calculation to two significant digits for each run or sample.
All rounding of numbers should be performed in accordance with the ASTM 380-76 procedures.
The nomenclature and sampling equations are presented in Sec. 7.4.1.
7.4.1
Sampling nomenclature
A
=
Cross sectional area of nozzle, m (ft ).
n
2
2
A
=
Cross sectional area of stack, m (ft ).
s
2
2
B
=
Water vapor in the gas stream, proportion by volume.
ws
C
=
Concentration of pollutant i, µg/dscm (lb/dscf).
i
E
=
Emission rate of pollutant i, g/sec (lb/hr).
i
D
=
Diameter of nozzle, mm (in.)
N
I
=
Percent of isokinetic sampling.
M
=
Molecular weight of water, 18.0 g/g-mole (18.0 lb/lb-mole).
w
M
=
Molecular weight of dry stack gas, g/g-mole (lb/lb-mole).
d
M
=
Molecular weight of wet stack gas, g/g-mole (lb/lb-mole).
s
m
=
Mass of pollutant i collected by sampling train, µg (lb).
i
P
=
Barometric pressure at the sampling site, mm Hg (in. Hg).
bar
P
=
Static gauge pressure of stack gas, mm H O (in. H O).
static
2
2
P
=
Absolute stack gas pressure, mm Hg (in. Hg).
s
P
=
Standard absolute pressure, 760 mm Hg (29.92 in. Hg).
std
Q
=
Average stack gas volumetric flow, dry, standard conditions, dscmm
sd
(dscfm).
R
=
Ideal gas constant, 0.06236 [(mm Hg) (m )] / [(
EK) (g-mole)] {21.85 [(in.
3
Hg) (ft )] / [(
ER) (lb-mole)]}.
3
T
=
Absolute average DGM temperature
EK (ER).
m

85.49
ft
sec
(lb/lb&mole) (in. Hg)
ER (in. H
2
0)
1/2
K
i
= 0.3858
EK/mm Hg for metric units, or
= 17.64
EF/in. Hg for English units.
V
w(std)
= V
lc
D
w
R T
std
M
w
P
std
= K
2
V
lc
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T
=
Absolute average stack gas temperature
EK (ER).
s
T
=
Standard absolute temperature, 293
EK (528ER).
std
V
=
Total volume liquid collected in impingers and silica gel (mL).
lc
V
=
Volume of gas sample as measured by dry gas meter, dcm (dcf).
m
V
=
Volume of gas sample measured by the dry gas meter, corrected to
m(std)
standard conditions, dscm (dscf).
V
=
Volume of water vapor in the gas sample, corrected to standard
w(std)
conditions, scm (scf).
V
=
Stack gas velocity, calculated by Method 2, Equation 2-9, using data
s
obtained from Method 5, m/sec (ft/sec).
Y
=
Dry gas meter calibration factor.
)P
=
Average pressure differential across pitot tube, mm H O (in.H O).
2
2
)H
=
Average pressure differential across the orifice meter, mm H O (in.
2
H O).
2
D
=
Density of water, 0.9982 g/mL (0.002201 lb/mL).
w
2
=
Total sampling time, min.
K
=
p
13.6
=
Specific gravity of mercury.
7.4.2
Dry gas volume - Correct the sample volume measured by the dry gas meter to
standard conditions (20
EC, 760 mm Hg or 68EF, 29.92 in. Hg) by using the following equation,
where:
If the leak corrections to sample volume are necessary and have been approved by the
test administrator, follow procedures listed in Method 0010.
7.4.3
Volume of water vapor

K
2
= 0.001333 m
3
/mL for metric units, or
= 0.04707 ft
3
/mL for English units.
B
ws
=
V
w(std)
V
m(std)
% V
w(std)
P
s
= P
bar
%
P
static
13.6
Dry: M
d
' (0.32 x %O
2
) × (0.44 x %CO
2
) %(0.28 x (100 & (%O
2
% %CO
2
))
Wet: M
s
= M
d
x (1 & B
ws
) % (B
ws
x M
w
)
V
s
= K
p
x C
p
x
)P x
T
s
% T
std
P
s
x M
s
Q
sd
= V
s
x A
s
x (1 & B
ws
) x
T
std
x P
s
T
s
x P
std
x
60 sec
min
C
i
=
M
i
V
m
(std)
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where:
7.4.4
Moisture content
NOTE:
In saturated or water droplet-laden gas streams, two calculations of the
moisture content of the stack gas should be made, one from the impinger
analysis (Sec. 7.4.3), and a second from the assumption of saturated
conditions. The lower of the two values of B should be considered correct.
ws
The procedure for determining the moisture content based upon assumption
of saturated conditions is given in a “Note” in Sec. 1 of Method 4. For the
purposes of this method, the average stack gas temperature may be used to
make this determination, provided that the accuracy of the in-stack
temperature sensor is ± 2
EC.
7.4.5
Absolute stack gas pressure
7.4.6
Average molecular weight of dry stack gas
7.4.7
Stack gas velocity at stack conditions
7.4.8
Average stack gas volumetric flow at dry, standard conditions
7.4.9
Concentration of pollutant

E
i
'
C
i
x Q
sd
60
sec
min
1 x 10
6
ug
g
%I '
1039.5746 x V
m
(std)
x (T
s
% 460)
V
s
x 2 x P
s
x (1 & B
ws
) x (D
n
)
2
(English units
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7.4.10 Emission of pollutant
7.4.11 Isokinetic sampling rate
8.0
QUALITY CONTROL
The following quality control (QC) guidelines outline pertinent steps to be followed during the
production of emission data to ensure and quantify the acceptability and reliability of the data
generated.
8.1
Sampling QC procedures - Quality control procedures specific to manual source gas
sampling procedures should follow EPA Method 5 and those listed in EPA Manual 600/4-77-0276
for Method 5. Sampling QC procedures are summarized in Table 2.
8.2
Blanks
8.2.1
Field blank - A field blank should be collected from a set of glassware that has
not been used to collect any field samples. In the case of results exceeding regulatory limits,
field blank data may be useful for convincing the regulatory official that contamination was the
cause. This may result in retesting rather than a violation charge. Collection of the field blank
is optional but recommended. Collect one field blank for every nine test runs at each test
location. 
8.2.2
Optional Glassware blank (proof blank) - A proof blank should be periodically
recovered from sampling train glassware that is used to collect organic samples. The
precleaned glassware, which consists of a probe liner, filter holder, condenser coil, and
impinger set, is loaded as if for sampling and then quantitatively recovered exactly as the
samples will be. Analysis of the generated fractions will ensure that laboratory contamination
levels are under control. 
8.2.3
Reagent blank - Reagent blanks should contain 500 mL of each reagent used at
the test site. Reagent blanks are saved for potential analysis. Each reagent blank is part of
the same lot used during the sampling program. If a field blank is unsatisfactory because of
contamination, reagent blanks may be analyzed to determine the specific source of
contamination. Collect one reagent blank per compliance test and archive for future analysis
in the event that the field blank shows contamination.
8.2.4
Laboratory method blank - A method blank is a performance control sample that
is prepared in the laboratory and processed in a manner identical to a field sample. The XAD-
2® resin should be from the same batch used for preparation of the field traps. One laboratory
method blank should be analyzed for every batch of samples analyzed.

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9.0
METHOD PERFORMANCE
9.1
Method performance evaluation - Evaluation of analytical procedures for a selected series
of compounds shall include the sample preparation procedures and each associated analytical
determination. The analytical procedures should be challenged by the test compounds spiked at
appropriate levels and carried through the procedures.
9.2
Method detection limit - The overall method detection limits (lower and upper) should be
calculated as shown in Sec. 6.2.3.1. Generally, analytical detection limit for tetra-CDD/CDF
congeners are 50 pg. Penta-, hexa-, and hepta- congener detection limits are 250 pg and octa-
congener detection limits are 500 pg.
9.3
Method precision and bias - The overall method precision and bias should be determined
on a compound-by-compound basis at a given concentration level. The method precision value
includes a combined variability due to sampling, sample preparation, and instrumental analysis. The
method bias is dependent upon the collection, retention, and extraction efficiency of the train
components. Interlaboratory testing of Method 0023 and Method 8290 to establish method accuracy
and precision for sampling a variety of stationary sources has not been performed.
10.0 REFERENCES
1.
American Society of Mechanical Engineers, Sampling for the Determination of Chlorinated
Organic Compounds in Stack Emissions. Prepared for U.S. Department of Energy and U.S.
Environmental Protection Agency. Washington, DC. December 1984.
2.
American Society of Mechanical Engineers. Analytical Procedures to Assay Stack Effluent
Samples and Residual Combustion Products for Polychlorinated Dibenzo-p-Dioxins (PCDD)
and Polychlorinated Dibenzofurans (PCDF). Prepared for the U.S. Department of Energy and
U.S. Environmental Protection Agency. Washington, DC. December 1984.
3.
Thompson, J.R., Analysis of Pesticide Residues in Human and Environmental Samples, U.S.
Environmental Protection Agency, Research Triangle Park, NC, 1974.
4.
Tondeur, Y., Albro, P.W., Hass, R.J., Harvan, D.J., Schroeder, J.L., "Matrix Effect in
Determination of 2,3,7,8-Tetrachlorodibenzodioxin by Mass Spectrometry", Anal. Chem. 56(8),
pp 1344-1347, 1984.
5.
Tondeur, Y., Niederhut, W.N., Campana, J.E., Missler, S.R., "A Hybrid HRGC/MS/MS Method
for the Characterization of Tetrachlorinated-p-Dioxins in Environmental Samples", Biomed.
Environ. Mass Spectrom. 14(8), pp 449-456, 1987.
6.
Taylor, J.K., Quality Assurance of Chemical Measurements, Lewis Publishers, Inc., 1987.
7.
Department of Health, Education, and Welfare, Public Health Service, Center for Disease
Control. Carcinogens - Working with Carcinogens. Publication No. 77-206. National Institute
for Occupational Safety and Health. August 1977.
8.
OSHA Safety and Health Standards, General Industry. 29 CFR, p 1910. Occupational Safety
and Health Administration. OSHA 2206. Revised January 1976.

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9.
American Chemical Society, Committee on Chemical Safety. Safety in Academic Chemistry
Laboratories. 3rd Edition, 1979.
10.
40 CFR Part 60, Appendix A.
11.
Martin, R.M., Construction Details of Isokinetic Source-Sampling Equipment. U. S.
Environmental Protection Agency, Research Triangle Park, NC. Air Pollution Technical
Document (APTD) 0581, April 1971.
12.
Rom, J.J., Maintenance, Calibration, and Operation of Isokinetic Source Sampling Equipment.
U.S. Environmental Protection Agency, Research Triangle Park, NC. Air Pollution Technical
Document (APTD) 0576, March 1972.

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TABLE 1
COMPOSITION OF THE SAMPLE FORTIFICATION 
AND RECOVERY STANDARDS SOLUTIONS

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