METHOD 8260D

VOLATILE ORGANIC COMPOUNDS BY GAS CHROMATOGRAPHY/MASS

SPECTROMETRY

Table of Contents

I.0	SCOPE AND APPLICATION	2

2.0 SUMMARY OF METHOD	7

3.0 DEFINITIONS	7

4.0 INTERFERENCES	7

5.0 SAFETY	8

6.0 EQUIPMENT AND SUPPLIES	8

7.0 REAGENTS AND STANDARDS	11

8.0 SAMPLE COLLECTION, PRESERVATION, AND STORAGE	13

9.0 QUALITY CONTROL	14

10.0 CALIBRATION AND STANDARDIZATION	18

II.0	PROCEDURE	18

12.0 DATA ANALYSIS AND CALCULATIONS	29

13.0 METHOD PERFORMANCE	30

14.0 POLLUTION PREVENTION	31

15.0 WASTE MANAGEMENT	31

16.0 REFERENCES	32

17.0 TABLES, DIAGRAMS, FLOWCHARTS, AND VALIDATION DATA	33

Appendix A: Summary of Revisions to Method 8260C (Rev 3, August 2006)	50

Appendix B: Guidance for Using Hydrogen Carrier Gas	52

Disclaimer

SW-846 is not intended to be an analytical training manual. Therefore, method
procedures are written based on the assumption that they will be performed by analysts who are
formally trained in at least the basic principles of chemical analysis and in the use of the subject
technology.

In addition, SW-846 methods, with the exception of required methods used for the
analysis of method-defined parameters, are intended to be guidance methods that contain
general information on how to perform an analytical procedure or technique. A laboratory can
use this guidance as a basic starting point for generating its own detailed standard operating
procedure (SOP), either for its own general use or for a specific project application. The
performance data referenced in this method are for guidance purposes only, and are not
intended to be and must not be used as absolute quality control (QC) acceptance criteria for
purposes of laboratory accreditation.

SW-846 Update VI

8260D - 1

Revision 4
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1.0 SCOPE AND APPLICATION

1.1 This method is used to determine volatile organic compounds (VOCs) in a variety
of solid waste matrices. This method is applicable to nearly all types of samples, regardless of
water content, including various air sampling trapping media, ground and surface water,
aqueous sludges, caustic liquors, acid liquors, waste solvents, oily wastes, mousses, tars,
fibrous wastes, polymeric emulsions, filter cakes, spent carbons, spent catalysts, soils, and
sediments. The following analytes have been determined by this method:

Analytes and Appropriate Preparation Techniques

Compound

CAS No.b

5030

5035

5031

5032

5021

5041

Direct
Inject

Acetone

67-64-1

*

*



S

_

~

~

Acetonitrile

75-05-8

*

*



-

-

-

~

Acrolein (Propenal)

107-02-8

*

*



-

-

-

~

Acrylonitrile

107-13-1

*

*



*

-

~

~

Allyl alcohol

107-18-6

*

-



-

-

-

~

Allyl chloride

107-05-1



*

-

-

-

-

~

f-Amyl ethyl ether (TAEE, 4,4-
Dimethyl-3-oxahexane)

919-94-8

*

*

-

-

¦/*

-

~

f-Amyl methyl ether (TAME)

994-05-8

*

*

-

-

•/*

-

~

Benzene

71-43-2





-



s

~

~

Benzyl chloride

100-44-7

*



-

-

-

-

~

Bromoacetone

598-31-2

*

-

-

-

-

-

~

Bromobenzene

108-86-1





-

V

-

-

-

Bromochloromethane

74-97-5





-

S

s

~

~

Bromodichloromethane

75-27-4





-

s

s

~

~

Bromoform

75-25-2

*

*

-

s

s

~

~

Bromomethane

74-83-9

*

*

-

s

s

~

~

n-Butanol (1-Butanol, n-Butyl
alcohol)

71-36-3

*

*



-

s

-

~

2-Butanone (MEK)

78-93-3

*

*





-

-

~

f-Butyl alcohol

75-65-0

*

*



-

s*

-

~

n-Butylbenzene

104-51-8





-

V

-

-

-

sec-Butylbenzene

135-98-8





-

s

-

-

-

te/f-Butylbenzene

98-06-6





-

s

-

-

-

Carbon disulfide

75-15-0

*

*

-

s

s

~

~

Carbon tetrachloride

56-23-5





-

s

s

~

~

Chloral hydrate

302-17-0

*

-

-

-

-

-

~

Chlorobenzene

108-90-7





-

s

s

~

~

1-Chlorobutane

109-69-3





-

s

-

-

-

Chlorodibromomethane
(Dibromochloromethane)

124-48-1





-

s

-

~

~

Chloroethane

75-00-3





-

s

s

~

~

2-Chloroethanol

107-07-3

*

-

-

-

-

-

~

2-Chloroethyl vinyl ether

110-75-8

*

*

-

-

-

-

~

Chloroform

67-66-3





-



s

~

~

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Compound

CAS No.b 5030 5035 5031 5032 5021 5041 , .

Inject

1-Chlorohexane
Chloromethane
Chloroprene (2-Chloro-1,3-
butadiene)

2-Chlorotoluene
4-Chlorotoluene
Crotonaldehyde
Cyclohexane

1,2-Dibromo-3-chloropropane
(DBCP)

1,2-Dibromoethane (EDB,
Ethylene dibromide)
Dibromomethane

1.2-Dichlorobenzene

1.3-Dichlorobenzene

1.4-Dichlorobenzene
cis-1,4-Dichloro-2-butene
trans-1,4-Dichloro-2-butene
Dichlorodifluoromethane

1.1-Dichloroethane

1.2-Dichloroethane

1.1-Dichloroethene	(Vinylidene
chloride)

cis-1,2-Dichloroethene
trans-1,2-Dichloroethene

1.3-Dichloropropane

1.2-Dichloropropane

2.2-Dichloropropane

1.3-Dichloro-2-propanol
1,1-Dichloropropene
cis-1,3-Dichloropropene
trans-^ ,3-Dichloropropene
1,2,3,4-Diepoxybutane
Diethyl ether
Diisopropyl ether (DIPE)

1.4-Dioxane
Epichlorohydrin
Ethanol

Ethyl acetate

Ethyl benzene

Ethyl methacrylate

Ethyl f-butyl ether (ETBE)

Ethylene oxide

Hexachlorobutadiene

Hexachloroethane

544-10-5

~

~

-

-

-

-

-

74-87-3

*

*

-

~

~

~

~

126-99-8

~

-

-

-

-

-

~

95-49-8

~

~

-

~

-

-

-

106-43-4

~

~

-

~

-

-

-

4170-30-3

*

-

*

-

-

-

~

110-82-7

~

~

-

~

-

-

-

96-12-8

*

*

-

~

~

-

~

106-93-4

~

~

-

~

~

-

~

74-95-3

~

~

.

~

~

~

~

95-50-1

~

~

-

~

~

-

~

541-73-1

~

~

-

~

~

-

~

106-46-7

~

~

-

~

~

-

~

1476-11-5

*

~

-

~

-

-

~

110-57-6

*

~

-

~

-

-

~

75-71-8

*

*

-

*

~

-

~

75-34-3

~

~

-

~

~

~

~

107-06-2

~

~

-

~

~

~

~

75-35-4

~

~

-

~

~

~

~

156-59-2

~

~

.

~

~

-

-

156-60-5

~

~

-

~

~

~

~

142-28-9

~

~

-

~

-

-

-

78-87-5

~

~

-

~

~

~

~

594-20-7

~

~

-

~

-

-

-

96-23-1

*

-

-

-

-

-

~

563-58-6

~

~

-

~

-

-

-

10061-01-5

~

~

-

~

-

~

~

10061-02-6

~

~

-

~

-

~

~

1464-53-5

~

-

-

-

-

-

~

60-29-7

*

*

-

*

-

-

~

108-20-3

*

~

-

-

¦/*

-

~

123-91-1

*

*

~

*

-

-

~

106-89-8

*

*

-

-

-

-

~

64-17-5

*

*

~

*

•/*

-

~

141-78-6

*

*

~

~

-

-

~

100-41-4

~

~

-

~

S

~

~

97-63-2

~

~

-

~

-

-

~

637-92-3

¦/*

¦/*

-

-

•/*

-

~

75-21-8

*

-

~

-

-

-

~

87-68-3

*

~

-

-

s

-

~

67-72-1

*

*

.

~

-

-

~

SW-846 Update VI

8260D - 3

Revision 4
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Compound

CAS No.b

5030

5035

5031

5032

5021

5041

Direct
Inject

2-Hexanone

591-78-6

*

*

-

~

-

-

~

lodomethane (Methyl iodide)

74-88-4

~

~

-

~

-

~

~

Isobutyl alcohol

78-83-1

*

*

~

-

~

-

~

Isopropylbenzene

98-82-8

~

~

-

~

~

-

~

p-lsopropyltoluene

99-87-6

~

~

-

~

-

-

-

Malononitrile

109-77-3

*

-

-

-

-

-

~

Methacrylonitrile

126-98-7

*

~

~

-

-

-

~

Methanol

67-56-1

*

-

~

-

-

-

~

Methyl acetate

79-20-9

~

~

-

~

-

-

-

Methyl acrylate

96-33-3

*

*

-

~

-

-

-

Methyl methacrylate

80-62-6

~

*

-

-

-

-

~

Methyl tert-butyl ether (MTBE)

1634-04-4

¦/*

¦/*

-

~

¦/*

-

~

Methylcyclohexane

108-87-2

S

S

-

~

-

-

-

Methylene chloride (DCM)

75-09-2

s

s

-

~

S

~

~

4-Methyl-2-pentanone (MIBK)

108-10-1

*

*

~

~

-

-

~

Naphthalene

91-20-3

*

*

-

~

y

-

~

Nitrobenzene (NB)

98-95-3

~

~

-

-

-

-

~

2-Nitropropane

79-46-9

~

~

-

-

-

-

~

/V-Nitroso-di-n-butylamine (N-
Nitrosodibutylamine)

924-16-3

*

-

~

-

-

-

~

Paraldehyde

123-63-7

*

-

~

-

-

-

~

Pentachloroethane

76-01-7

*

*

-

*

-

-

~

Pentafluorobenzene

363-72-4

~

~

-

~

-

-

-

2-Pentanone

107-87-9

*

~

~

-

-

-

~

2-Picoline (2-Methylpyridine)

109-06-8

*

*

~

-

-

-

~

1-Propanol (n-Propyl alcohol)

71-23-8

*

*

~

-

-

-

~

2-Propanol (Isopropyl alcohol)

67-63-0

*

*

~

-

s

-

~

Propargyl alcohol

107-19-7

*

-

-

-

-

-

~

P-Propiolactone

57-57-8

*

-

-

-

-

-

~

Propionitrile (Ethyl cyanide)

107-12-0

~

~

~

-

-

-

-

n-Propylamine

107-10-8

¦/*

-

-

-

-

-

~

n-Propylbenzene

103-65-1

s

~

-

~

-

-

-

Pyridine

110-86-1

*

*

~

*

-

-

~

Styrene

100-42-5

*

*

-

~

•/*

~

~

1,1,1,2-T etrachloroethane

630-20-6

~

~

-

~

s

~

~

1,1,2,2-T etrachloroethane

79-34-5

¦/*

¦/*

-

~

•/*

~

~

Tetrachloroethene

127-18-4

•/*

s

-

~

•/*

~

~

Toluene

108-88-3

s

s

-

~

s

~

~

o-Toluidine

95-53-4

*

-

~

-

-

-

~

1,2,3-T richlorobenzene

87-61-6

*

*

-

~

s

-

~

1,2,4-T richlorobenzene

120-82-1

*

*

-

~

s

-

~

1,1,1-Trichloroethane

71-55-6

~

~

-

~

s

~

~

1,1,2-T richloroethane

79-00-5

~

~

-

~

s

~

~

Trichloroethene
(Trichloroethylene)

79-01-6

¦/*

~

-

~

•/*

~

~

SW-846 Update VI

8260D - 4









Revision 4

February 2017

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Compound

CAS No.b

5030

5035 5031

5032

5021

5041

Direct
Inject

1,1,2-T richloro-1,2,2-

76-13-1

~

~

~







trifluoroethane













1,1,1 -T richlorotrifluoroethane

354-58-5

~

~

~

-

-

-

T richlorofluoromethane

75-69-4

*

*

~

~

~

~

1,2,3-T richloropropane

96-18-4

~

~

~

~

~

~

1,2,3-T rimethylbenzene

526-73-8

-

-

-

~

-

-

1,2,4-T rimethylbenzene

95-63-6

~

~

~

~

-

-

1,3,5-T rimethylbenzene

108-67-8

~

~

~

~

-

-

Vinyl acetate

108-05-4

*

*

-

-

-

~

Vinyl chloride

75-01-4

*

*

~

~

~

~

m-Xylene

108-38-3

~

~

~

~

~

~

o-Xylene

95-47-6

~

~

~

~

~

~

p-Xylene

106-42-3

~

~

~

~

~

~

a See Sec. 1.2 for other appropriate sample preparation techniques.
b Chemical Abstract Service Registry Number

KEY TO ANALYTE LIST

S Historically, adequate recovery and precision can be obtained for this analyte by this
technique. However, actual recoveries may vary depending on the sample matrix, preparation
technique, and analytical instrumentation. Data from a large multi-laboratory study for 5030
and 5035 is available in Table 2. Compounds with this flag had a relative standard deviation
(RSD) <15% in a multi-laboratory study.

Not determined

* This analyte exhibits known difficulties with reproducibility, response, recovery,
stability, and/or chromatography that may reduce the overall quality or confidence in the result
when using this preparation method combined with analysis by Method 8260 (e.g., multi-
laboratory study data with a RSD > 15%). This analyte may require special treatment (see
Sec. 1.3) to improve performance to a level that would meet the needs of the project and, where
necessary, may also require the use of appropriate data qualifiers if the relevant performance
criteria cannot be met.

S* This analyte meets the criteria for adequate performance using this technique (see
definition for S)\ however, it is known to exhibit problems listed in Sec. 1.3 (see definition for *).

1.2 The compounds listed above may be introduced into the gas
chromatograph/mass spectrometer (GC/MS) system by various techniques. The techniques
listed in the table above have performance data available. Purge-and-trap, by Methods 5030
(aqueous samples) and 5035 (solid and waste oil samples), is the most commonly used
technique for VOCs. However, other techniques are also appropriate and may yield better
performance for some analytes.

These include: direct injection after dilution with hexadecane (Method 3585) for waste oil
samples; automated static headspace by Method 5021 for solid and aqueous samples; direct
injection of an aqueous sample (concentration permitting) or injection of a sample concentrated
by azeotropic distillation (Method 5031); and vacuum distillation (Method 5032) for aqueous,
solid, oil and tissue samples. For air samples, Method 5041 provides methodology for
desorbing VOCs from trapping media (Methods 0010, 0030, and 0031). In addition, direct

SW-846 Update VI	8260D - 5	Revision 4

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analysis utilizing a sample loop is used for sub-sampling from polytetrafluoroethylene (PTFE)
bags (Method 0040), also referred to as Tedlar® bags. Method 5000 provides more general
information on the selection of the appropriate introduction method.

1.3	Special considerations for compounds noted with * in the table in Sec. 1.1.

1.3.1	Recovery of bases from water will be affected by pH. Compounds such
as pyridine, o-toluidine, n-propylamine and 2-picoline will have poor to no recovery from
low pH water. 2-Chloroethyl vinyl ether is subject to hydrolysis at low pH.

1.3.2	Dehydrohalogenation may result in degradation of aqueous solutions of
pentachloroethane and to a lesser extent, other halogenated compounds (e.g.,
dichlorobutenes and 1,1,2,2-tetrachloroethane) to other target analytes (especially
tetrachloroethene and trichloroethene) if the pH is >4 (see Reference 6 in Sec. 16 for
further information on this topic). The use of hydrogen carrier gas may also cause the
dehydrohalogenation of these analytes.

1.3.3	Alcohols, ketones, ethers and other water-soluble compounds will have
low responses. Elevated sample temperatures may be necessary during purges as
heated samples will exhibit better performance of these analytes. However, ethers
such as diethyl ether and MTBE hydrolyze more readily when heated in acid-preserved
water. Acid preservation is not recommended for analysis of these target analytes at
elevated sample temperature. Higher concentrations for calibration standards may also
be appropriate. Methanol is used as a solvent for standards in this analysis.

Therefore, special conditions and alternate standards will be required for analyses where
it is a target analyte.

1.3.4	Aldehydes (e.g., acrolein, paraldehyde, crotonaldehyde) are included in
the target list but have poor stability under the analytical conditions used in this method.
Other methods may be more appropriate for these compounds.

1.3.5	Heavier target compounds (e.g., naphthalene, 1,2-dibromo-3-
chloropropane and hexachlorobutadiene) will have lower overall response and greater
variability with conditions and concentrations.

1.3.6	Compounds that are gases at room temperature (e.g.,
chlorofluorocarbons, chloromethane and vinyl chloride) are prone to loss through vial
seals and in handling. In addition, compounds co-eluting with water and methanol will
have their responses suppressed.

1.3.7	Vinyl chloride and styrene are subject to loss due to chemical reactivity.
Preservation by acidification does not prevent this.

1.4	Prior to employing this method, analysts are advised to consult the base method
for each type of procedure that may be employed in the overall analysis (e.g., Methods 5000
and 8000) for additional information on QC procedures, development of QC acceptance criteria,
calculations, and general guidance. Analysts also should consult the disclaimer statement at
the front of the SW-846 manual and the information in Chapter Two for guidance on the
intended flexibility in the choice of methods, apparatus, materials, reagents, supplies, and on
the responsibilities of the analyst for demonstrating that the techniques employed are
appropriate for the analytes of interest, in the matrix of interest, and at the levels of concern.

In addition, analysts and data users are advised that, except where explicitly specified in
a regulation, the use of SW-846 methods is not mandatory in response to Federal testing

SW-846 Update VI

8260D - 6

Revision 4
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requirements. The information contained in this method is provided by the Environmental
Protection Agency (EPA or the Agency) as guidance to be used by the analyst and the
regulated community in making judgments necessary to generate results that meet the data
quality objectives (DQOs) for the intended application.

1.5 This method is restricted to use by, or under supervision of, personnel
appropriately experienced and trained in the use of GC/MS and skilled in the interpretation of
mass spectra. Each analyst must demonstrate the ability to generate acceptable results with
this method.

2.0 SUMMARY OF METHOD

2.1	VOCs are introduced into the GC by one of the preparation methods mentioned in
Sec. 1.2. The analytes may be introduced directly to a capillary column, cryofocused on a
capillary pre-column before being flash evaporated to a capillary column for analysis, or
desorbed from a trap and sent to an injection port operating in the split mode for injection to a
capillary column. The column is temperature-programmed to separate the analytes, which are
then detected with a MS interfaced to the GC.

2.2	Analytes eluted from the capillary column are introduced into the MS via a direct
connection or flow splitter. Some wide-bore capillary columns may require splitting the flow
prior to the MS interface, whereas narrow-bore capillary columns may be directly interfaced to
the ion source or used with a restrictor column at the MS interface. Identification of target
analytes is accomplished by comparing their mass spectra and retention times (RTs) with the
mass spectra and RTs of known standards for the target compounds. Quantitation is
accomplished by comparing the response of a major (quantitation) ion relative to an internal
standard (IS) using an appropriate calibration curve for the intended application.

2.3	The method includes specific calibration and QC steps that supersede the general
requirements provided in Method 8000.

3.0 DEFINITIONS

Refer to Chapter One and the manufacturer's instructions for definitions that may be
relevant to this procedure.

4.0 INTERFERENCES

4.1	In order to avoid compromising data quality, contamination of the analytical system
by volatile materials from the laboratory must be reduced to the lowest practical level. Refer to
each preparation method for specific guidance on QC procedures and to Chapter Four for
general guidance on the cleaning of glassware. Refer to Method 8000 for a discussion of
interferences.

4.2	Volatile preparation and analysis should be physically separated from laboratory
areas where target solvents are used. Air supply for the volatiles area should provide positive
pressure relative to other laboratory areas. The water supply used for blanks should be
isolated from target solvents and free of plastic supply piping.

4.3	Cross contamination may occur when a sample containing low concentrations of
VOCs is analyzed immediately after a sample containing high concentrations of VOCs. After

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analysis of a sample containing high concentrations of VOCs, analysis of one or more blanks
may be used to demonstrate that carryover is not a significant portion of the target response in
subsequent samples.

4.4	For samples that may contain large amounts of surfactants, suspended solids, high
boiling compounds, high concentrations of target analytes or other non-target interferences,
screening samples with another technique prior to purge-and-trap GC/MS analysis is prudent to
prevent system contamination.

4.5	Control of contaminants is assessed by analysis of blanks. Transport (trip),
calibration and reagent blanks provide information about the presence of contaminants at
different points in the analytical process. Where measured analyte concentrations are
suspected of being biased high or having false positive results due to contamination, affected
data should be qualified, and the data user should otherwise be informed of any suspected data
quality issues. Subtracting blank values from sample results is not permitted.

5.0 SAFETY

This method does not address all safety issues associated with its use. The laboratory is
responsible for maintaining a safe work environment and a current awareness file of
Occupational Safety and Health Administration (OSHA) regulations regarding the safe handling
of the chemicals listed in this method. A reference file of safety data sheets (SDSs) must be
available to all personnel involved in these analyses. If hydrogen is used as a carrier gas, see
Appendix B.

6.0 EQUIPMENT AND SUPPLIES

The mention of trade names or commercial products in this manual is for illustrative
purposes only, and does not constitute an EPA endorsement or exclusive recommendation for
use. The products and instrument settings cited in SW-846 methods represent those products
and settings used during method development or subsequently evaluated by the Agency.
Glassware, reagents, supplies, equipment, and settings other than those listed in this manual
may be employed provided that method performance appropriate for the intended application
has been demonstrated and documented.

6.1 This section does not list common laboratory glassware (e.g., beakers and flasks).

6.1.1	Purge-and-trap device for aqueous samples as described in Method 5030

6.1.2	Purge-and-trap device for solid samples as described in Method 5035

6.1.3	Automated static headspace device for solid and aqueous samples as
described in Method 5021

6.1.4	Azeotropic distillation apparatus for aqueous and solid samples as
described in Method 5031

6.1.5	Vacuum distillation apparatus for aqueous, solid and tissue samples as
described in Method 5032

6.1.6	Desorption device for air trapping media for air samples as described in
Method 5041

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6.1.7 Air sampling loop for sampling from Tedlar® bags for air samples as
described in Method 0040

6.2 GC/MS system

6.2.1	GC - An analytical system complete with a temperature-programmable
GC suitable for splitless injection with an appropriate interface or direct split interface for
sample introduction. The system includes all required accessories, including syringes,
analytical columns, and gases. If hydrogen is used as a carrier gas, see Appendix B.

6.2.1.1	The GC should be equipped with flow controllers such that the
column flow rate remains constant throughout desorption and temperature
program operation.

6.2.1.2	For some column configurations, the column oven must be
cooled to less than 30 °C. Therefore, a sub-ambient oven controller may be
necessary.

6.2.1.3	A capillary column can be directly coupled to the ion source of
the MS or interfaced through a separator, depending on the size of the capillary
and the requirements of the GC/MS system.

6.2.1.4	GC columns - The following columns have been found to
provide good separation of VOCs:

•	30 m x 0.25 mm internal diameter (ID), 1,4-|jm film thickness, DB-624 or
VOCOL;

•	20 m x 0.18 mm ID, 1-|jm film thickness, DB-VRX;

•	60 m x 0.32 mm ID, 1,5-|jm or 1,8-|jm film thickness, Rtx-Volatiles.

The following columns were used to generate performance data cited in
the references:

•	30 m x 0.25 - 0.32 mm ID, 1-|jm film thickness, DB-5, Rtx-5, SPB-5; and

•	75 m x 0.53 mm ID, 3-|jm film thickness, DB-624, Rtx-502.2, or VOCOL.

6.2.2	MS

6.2.2.1	Capable of acquiring mass spectra from mass/charge (m/z) 35
to 270 at a rate fast enough to acquire at least five (but preferably 10 or more)
mass spectra across each chromatographic peak of interest, using 70 volts
(nominal) electron energy in the electron impact ionization mode. The MS must
be capable of meeting the criteria as outlined in Sec. 11.3.1.

6.2.2.2	An ion trap MS may be used if it is capable of axial modulation
to reduce ion-molecule reactions and can produce electron impact-like spectra
that match those in the EPA/National Institute on Standards and Technology
(NIST) library or equivalent. Because ion-molecule reactions with water and
methanol in an ion trap MS may produce interferences that co-elute with
chloromethane and chloroethane, the base peak for both of these analytes will
be at m/z 49, which should also be used as the quantitation ion in this case.
The MS must be capable of producing a mass spectrum which meets the criteria
as outlined in Sec. 11.3.1.

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6.2.2.3	A tandem MS (MS/MS) may be used if it has the necessary
pumps, collision cell, collision gases, and high-vacuum system capable of
performing transitions in product ion scan mode or the selected reaction
monitoring mode (SRM) for the target analytes of interest. Recommendations
for specific precursor and product ions in SRM are available for some target
analytes from the manufacturers of the equipment. The system must be
capable of documenting the performance of both MSs against manufacturer
specifications for mass resolution, mass assignment, and sensitivity using the
internal calibrant (e.g., perfluorotributylamine). It is recommended to check the
performance of the system at least weekly or at a frequency appropriate to meet
the needs of the project. At a minimum, the performance of the system must be
checked just prior to the initial calibration (ICAL).

6.2.2.4	The use of a selected ion monitoring (SIM) or chemical
ionization (CI) mass spectrometry are acceptable techniques for applications
requiring quantitation limits below the normal range of electron impact mass
spectrometry or to reduce interferences from the sample matrix.

6.2.3	GC/MS interface - One of the following examples may be used to
interface the GC to the MS.

6.2.3.1	Direct coupling, by inserting the column into the MS through a
heated transfer line, is generally used for capillary columns < 0.53 mm ID.

6.2.3.2	A jet separator, including an all-glass transfer line and glass
enrichment device or split interface, is used with columns > 0.53 mm ID.

6.2.3.3	Other interfaces may be used provided the performance
specifications described in Sec. 11.3.1 are achieved.

6.2.4	Data system - A computer system that allows the continuous acquisition
and storage of all mass spectra obtained throughout the duration of the chromatographic
program must be interfaced to the MS. The computer must have software that allows
searching any GC/MS data file for ions of a specified mass and plotting such ion
abundances versus time or scan number. This type of plot is defined as an extracted
ion current profile (EICP). Software must also be available that allows integrating the
abundances in any EICP between specified time or scan-number limits. A recent
version of the EPA/NIST mass spectral library, or equivalent, should also be available.

6.3	Microsyringes - 10, 25, 100, 250, 500, and 1000 |jL gas-tight

6.4	Syringe valve - Two-way, with Luer ends (three each), if applicable to the
purging device

6.5	Syringes - 5, 10, or 25 ml_, gas-tight with shutoff valve

6.6	Balance - Analytical, capable of weighing 0.0001 g, and top-loading, capable of
weighing 0.1 g

6.7	Glass VOA vials - 20, 40, 60 ml_, with PTFE-lined screw-top or crimp-top caps
(compatible with the autosampler if appropriate for the preparation technique)

6.8	Vials-for GC autosampler

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6.9 Disposable pipets - Pasteur

6.10	Volumetric flasks, Class A-5, 10, 50, 100 mL, with ground-glass stoppers

6.11	Spatula - Stainless steel

7.0 REAGENTS AND STANDARDS

7.1	Reagent-grade chemicals must be used in all tests. Unless otherwise indicated,
it is intended that all reagents conform to the specifications of the Committee on Analytical
Reagents of the American Chemical Society (ACS), where such specifications are available at:
http://pubs.acs.orq/reaqents/comminfo/techquestions.html. Other grades may be used,
provided it is first ascertained that the reagent is of sufficiently high purity to permit its use
without lessening the accuracy of the determination. Reagents should be stored in glass to
prevent the leaching of contaminants from plastic containers.

7.2	Organic-free reagent water - All references to water in this method refer to
organic-free reagent water, as defined in Chapter One.

7.3	Methanol, CH3OH - Purge-and-trap grade or equivalent, demonstrated to be free
from interferences for the compounds of interest at their lower limit of quantitation (LLOQ).

Store this solvent apart from other solvents to avoid contamination.

7.4	Hexadecane - Reagent grade, or equivalent, demonstrated to be free from
interferences for the compounds of interest at the levels of interest through the analysis of a
solvent blank. The results of such a blank analysis must demonstrate that no interfering
volatiles are present.

7.5	1:1 Volume/volume (v/v) hydrochloric acid (HCI/water) - Carefully add a
measured volume of concentrated HCI to an equal volume of organic-free reagent water.

7.6	Stock standard solutions - The solutions may be purchased as certified solutions
or prepared from pure standard materials. Commercially prepared stock standards may be
used at any concentration if they are certified by an accredited supplier or third party. Prepare
stock standard solutions in methanol (or other appropriate solvent), using assayed liquids or
gases, as appropriate.

7.7	Working standards - Using stock standard solutions, prepare working standards
in methanol (or other appropriate solvent), containing the compounds of interest, either singly or
mixed together. Working standards must be stored with minimal headspace and should be
checked frequently for signs of degradation or evaporation, especially just prior to preparing
calibration standards. Working standards for most compounds should be replaced after four
weeks unless the integrity of the standard is suspected of being compromised prior to that time.
Working standards for gases should be replaced after one week unless the acceptability of the
standard can be documented. When using premixed certified solutions, store according to the
manufacturer's documented holding time and storage temperature recommendations.

7.8	Surrogate standards - Recommended general-use surrogates are toluene-dg,
4-bromofluorobenzene (BFB), and 1,2-dichloroethane-d4. Other compounds with
physicochemical properties better resembling the analyte classes of interest may be used as
surrogates (e.g., deuterated monitoring compounds in the EPA Contract Laboratory Program's
(CLP) current statement of work, which can be found in Reference 14 in Sec. 16), provided they
can be unambiguously identified and meet any applicable acceptance criteria described in Sec.

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11 for ICAL and continuing calibration verification (CCV). A stock surrogate solution in
methanol should be prepared, and a surrogate standard spiking solution should be prepared
from the stock at an appropriate concentration in methanol. Each sample undergoing GC/MS
analysis must be spiked with the surrogate spiking solution prior to analysis.

7.9	Internal standards (IS) - The recommended ISs are fluorobenzene,
chlorobenzene-ds, and 1,4-dichlorobenzene-d4. Other compounds may be used as ISs as long
as they have RTs similar to their target compounds, they can be unambiguously identified and
meet any applicable acceptance criteria described in Sec. 11. See Sec. 11.4.3 of Method 8000
for additional information. Prepare the ISs solution in methanol (or other appropriate solvent).

7.10	BFB tune verification standard - A standard solution of BFB in methanol (or other
appropriate solvent) may be prepared for direct injection. If BFB is used as a surrogate, the
surrogate solution may be used for this purpose.

7.11	Calibration standards - There are two types of calibration standards used for this
method: standards made from the primary source (for ICAL and CCV) and standards made from
a second source for initial calibration verification (ICV). When using premixed certified solutions,
store according to the manufacturer's documented holding time and storage temperature
recommendations.

7.11.1	ICAL standards must be prepared at a minimum of five different
concentrations from the working dilution of stock standards or from premixed certified
solutions. Prepare these solutions in organic-free reagent water or in a solvent
appropriate for the specific sample preparation method used. Include a minimum of five
different concentrations in the calibration for average response factor (RF) or linear (first-
order) calibration models or six different concentrations for a quadratic (second-order)
model, with the low standard at or below the LLOQ (see Sec. 9.9 and Method 8000). At
least one of the calibration standards should correspond to a sample concentration at or
below that necessary to meet the DQOs of the project. The remaining standards should
correspond to the range of concentrations found in typical samples but should not
exceed the working range of the GC/MS. ICAL standards should be mixed from fresh
stock standards and dilution standards when generating an ICAL curve.

7.11.2	CCV standards should be prepared at a concentration near the mid-
point of the ICAL from the same source as the ICAL.

7.11.3	Second source standards for ICV must be prepared using source
materials from a second manufacturer or from a manufacturer's batch prepared
independently from the batch used for calibration. Target analytes in the ICV are
recommended to be prepared at concentrations near the mid-point of the calibration
range. The standard should contain all calibrated target analytes that will be reported
for the project, if readily available. See Sees. 9.3.2 and 11.3.6 for guidance and
acceptance limits.

7.11.4	It is the intent of EPA that all target analytes for a particular analysis be
included in the ICAL and CCV standard(s). These target analytes may not include the
entire list of analytes (Sec. 1.1) for which the method has been demonstrated.

However, the laboratory shall not report a quantitative result for a target analyte that was
not included in the calibration standards.

7.12	Matrix spike and LCS standards - See Method 5000 for instructions on preparing
the matrix spike standard. Matrix spikes and LCSs should be prepared with target analytes
from the same source as the ICAL standards to restrict the influence of accuracy on the

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determination of recovery throughout preparation and analysis. Add VOCs to matrix spikes
and LCS standards that are representative of the compounds being investigated. It is
recommended to include all reported target analytes in all LCS and matrix spiked samples. For
some applications, a limited set of representative analytes is acceptable.

7.13	Great care must be taken to maintain the integrity of all standard solutions. It is
recommended that standards be stored with minimal headspace, protected from light, at <6
°C, or as recommended by the standard manufacturer using screw-cap or crimp-top amber
containers equipped with PTFE liners. Returning standards to the refrigerator or freezer
immediately after standard and sample preparation is completed will help maintain the integrity
of the solutions and minimize loss of volatile target compounds. ISs and surrogates spiking
solutions added by the instrument do not need to be refrigerated provided they are sealed to
prevent loss.

7.14	Carrier gas - Helium or hydrogen may be used as a carrier gas. If hydrogen is
used, analytical conditions may need to be adjusted for optimum performance and calibration,
and all QC tests must be performed with hydrogen carrier gas. See Appendix B for guidance.

8.0 SAMPLE COLLECTION, PRESERVATION, AND STORAGE

Sample collection, preservation and storage requirements may vary by EPA program
and may be specified in a regulation or project planning document that requires compliance
monitoring for a given contaminant. Where such requirements are specified in a regulation,
follow those requirements. In the absence of specific regulatory requirements, use the following
information as guidance in determining the sample collection, preservation and storage
requirements.

8.1	See Chapter Four, "Organic Analytes", for storage condition and holding times.

8.2	Aqueous samples should be stored with minimal or no headspace to minimize
the loss of highly volatile analytes.

8.3	Solid and waste samples should be collected in air-tight containers compatible
with closed-system sample preparation and analysis techniques, if possible. Samples
must be handled carefully to minimize loss of VOCs during sample collection, shipping,
storage, preparation and analysis. Refer to Chapter 4 and to American Society for
Testing and Materials (ASTM) D4547 (Reference 18) for more information.

8.4	Samples to be analyzed for VOCs should be stored separately from standards
and from other samples expected to contain significantly different concentrations of volatile
compounds, or from samples collected for the analysis of other parameters such as
semivolatiles.

8.5	Blanks should be used to monitor potential cross-contamination of samples due
to improper handling or storage conditions. The specifics of this type of monitoring activity
should be outlined in a laboratory SOP or project planning documents pertaining to volatiles
sampling.

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9.0 QUALITY CONTROL

9.1	Refer to Chapter One for guidance on quality assurance (QA) and QC protocols.
When inconsistencies exist between QC guidelines, method-specific QC criteria take
precedence over both technique-specific criteria and those criteria given in Chapter One, and
technique-specific QC criteria take precedence over the criteria in Chapter One. Any effort
involving the collection of analytical data should include development of a structured and
systematic planning document, such as a quality assurance project plan (QAPP) or a sampling
and analysis plan (SAP), which translates project objectives and specifications into directions for
those who will implement the project and assess the results. Each laboratory should maintain

a formal QA program. The laboratory should also maintain records to document the quality of
the data generated. All data sheets and QC data should be maintained for reference or
inspection.

9.2	Refer to Method 8000 for general QC procedures for organic determinative
methods. Refer to Method 5000 for QC procedures to ensure the proper operation of the
various sample preparation techniques. Any more specific QC procedures provided in this
method will supersede those noted in Methods 8000 and 5000.

9.3	QC procedures necessary to evaluate GC system operation are found in Method
8000 and include evaluation of RT windows, calibration verification and chromatographic
analysis of samples. In addition, discussions regarding the instrument QC categories,
minimum frequency and criteria listed below can be found in the referenced sections of this
method, and a summary is provided in Table 7. Quantitative sample analyses should not
proceed for those analytes that do not meet the QC acceptance criteria. However, analyses
may continue for those analytes that do not meet the criteria with an understanding that these
results could be used for screening purposes and would be considered estimated values.

9.3.1	The GC/MS tune must be verified to meet acceptance criteria prior to
ICAL. Acceptance criteria are primarily intended to verify mass assignments and mass
resolution under the same conditions used for analysis. See Sec. 11.3.1 for further
details.

9.3.2	There must be an ICAL of the GC/MS system as described in Sec. 11.3.
Prior to analyzing samples, the ICAL must be verified using a second source ICV
standard, if readily available (Refer to Sec. 11.3.6).

9.3.3	Calibration of the system must be verified periodically by analysis of a
CCV standard. See Sec. 11.4 for the frequency and acceptance criteria.

9.4	Initial demonstration of proficiency (IDP) - Prior to implementation of a method,
each laboratory must perform an IDP consisting of at least four replicate reference samples
spiked into a clean matrix taken through the entire sample preparation and analysis. If an
autosampler is used to make sample dilutions, the accuracy of the dilutions should be evaluated
prior to sample analysis. Whenever a significant change to instrumentation or procedure
occurs, the laboratory must demonstrate that acceptable precision and bias can still be
obtained. Also, whenever new staff members are trained, each analyst must perform an IDP
for the method or portion of the method for which the analyst is responsible. This
demonstration should document that the new analyst is capable of successfully following the
SOP established by the laboratory and meeting any applicable acceptance criteria specified
therein. Refer to Sec. 9.3 of Method 8000 for more information on how to perform an IDP.

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9.5	Blanks

9.5.1	Before processing any samples, the analyst must demonstrate through
the analysis of a method blank (MB) or instrument blank that equipment and reagents
are free from contaminants and interferences. If a peak is found in the blank that would
prevent the identification or bias the measurement of an analyte, the analyst should
determine the source and eliminate it, if possible. As a continuing check, each time a
batch of samples is analyzed, and when there is a change in reagents, a MB must be
prepared and analyzed for the compounds of interest as a safeguard against chronic
laboratory contamination. MBs, trip blanks, and other field blanks must be carried
through all stages of sample preparation and analysis. At least one MB must be
analyzed on every instrument after calibration standard(s) and prior to the analysis of
any samples. Blank(s) analyzed after a high concentration calibration standard can
also be used to estimate the extent of decontamination needed to reduce the signal to
an acceptable level (Sec. 9.5.2) after analyzing a sample at a similar concentration.

9.5.2	Blanks are generally considered to be acceptable if target analyte
concentrations are less than one half the LLOQ or are less than project-specific
requirements. Blanks may contain analyte concentrations greater than acceptance
limits if the associated samples in the batch are unaffected (i.e., targets are not present
in samples or sample concentrations/responses are >10X the blank). Other criteria may
be used depending on the needs of the project.

9.5.3	If an analyte of interest is found in a sample in the batch near a
concentration confirmed in the blank (refer to Sec. 9.5.2), the presence and/or
concentration of that analyte should be considered suspect and may require
qualification. Contaminants in the blank should meet most or all of the qualitative
identifiers in Sec. 11.6 to be considered. Samples may require re-analysis if the blanks
do not meet laboratory-established or project-specific criteria. Re-analysis is not
necessary if the analyte concentration falls well below the action or regulatory limit or if
the analyte is deemed not important for the project.

9.5.4	When new reagents or chemicals are received, the laboratory should
monitor the blanks associated with samples for any signs of contamination. It is not
necessary to test every new batch of reagents or chemicals prior to sample preparation
if the source shows no prior problems. However, if reagents are changed during a
preparation batch, separate blanks must be prepared for each set of reagents.

9.5.5	The laboratory should not subtract the results of the MB from those of
any associated samples. Such "blank subtraction" may lead to negative sample results.
If the MB results do not meet project-specific acceptance criteria and reanalysis is not
practical, then the data user should be provided with the sample results, the MB results,
and a discussion of the corrective actions undertaken by the laboratory.

9.6	Sample QC for preparation and analysis - The laboratory must also have
procedures for documenting the effect of the sample matrix on method performance (i.e.,
precision, bias, and method sensitivity). At a minimum, this must include the analysis of a MB,
an LCS, and should include either a laboratory sample duplicate/matrix spike or matrix
spike/matrix spike duplicate (where practical and sample volume is available for doing so) in
each preparation batch, as well as monitoring the recovery of surrogates. These QC samples
should be subjected to the same analytical procedures (Sec. 11.0) as those used on the field
samples.

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9.6.1	A MB must be included with each analytical batch. MBs consist of an
aliquot of clean (control) matrix similar to the sample and of a similar weight or volume.
Other types of blanks (e.g., trip blanks, storage blanks, etc.) should be included when
appropriate but are distinct from MBs.

9.6.2	An LCS must be included with each analytical batch. The LCS consists
of an aliquot of a clean (control) matrix similar to the sample matrix and of the same
weight or volume. The LCS is spiked with the same analytes at the same concentrations
as the matrix spike, when appropriate. When the results of the matrix spike analysis
indicate a potential problem due to the sample matrix itself, the LCS results are used to
verify that the laboratory can perform the analysis in a clean matrix. The LCS for water
sample matrices is typically prepared in organic-free reagent water similar to the CCV
standard. The LCS for solid matrices is typically prepared in clean sand and organic-
free reagent water, similar to the CCV standard. When an LCS is prepared in the same
manner as a CCV, the same standard can be used as both the LCS and CCV. The
CCV acceptance criteria may be used for evaluation in this situation. Consult Method
8000 for information on developing acceptance criteria for the LCS.

9.6.3	Documenting the effect of the matrix on target analyte measurements
should include the analysis of at least one matrix spike and one duplicate unspiked
sample or one matrix spike/matrix spike duplicate pair. The decision of whether to
prepare and analyze duplicate samples or a matrix spike/matrix spike duplicate must be
based on knowledge of the samples, the project goals and should be addressed in the
project planning documents. If samples are expected to contain reportable levels of
target analytes, then laboratories may use one matrix spike and a duplicate analysis of a
non-spiked field sample. If samples are not expected to contain reportable levels of
target analytes, laboratories may use a matrix spike and matrix spike duplicate pair.
Consult Method 8000 for information on developing acceptance criteria for the matrix
spike/matrix spike duplicate pair. When spiking solid samples in an aqueous mixture, it
is not practical to expect analyte behavior equivalent to an exposure that occurred in
field conditions. Therefore, it is understood that matrix spikes are used to estimate the
severity of matrix effects that can be observed within method constraints.

9.6.4	See Method 8000 for more details on carrying out QC procedures for
preparation and analysis. In-house criteria for evaluating method performance should
be developed using the guidance found in Method 8000.

9.7	Surrogate recoveries - Surrogates must be added to every blank, field sample,
laboratory QC, and field QC. The laboratory should evaluate surrogate recovery data from
individual samples relative to the surrogate recovery acceptance criteria developed by the
laboratory. See Method 8000 for information on evaluating surrogate data and developing and
updating surrogate recovery acceptance criteria. Suggested surrogate recovery limits for field
samples are 70 to 130% until laboratory or project-specific criteria can be developed. Limits
will depend on the surrogates chosen, levels used, and instrument conditions. Procedures for
evaluating the recoveries of multiple surrogates and associated corrective actions should be
defined in the laboratory's SOP or in an approved project plan.

9.8	IS responses must be monitored to ensure sensitivity is maintained and to limit
the potential for measurement bias of associated target analyte concentrations. IS responses
in field samples are compared to responses of the same ISs in the ICAL standards or CCV
standards, with suggested acceptance criteria provided in Sec. 11.5.6. When IS responses fall
outside the acceptance range, further investigation is warranted, and results may require
qualification for detects and non-detects.

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9.9. Lower limit of quantitation (LLOQ) - The LLOQ is the lowest concentration at
which the laboratory has demonstrated target analytes can be reliably measured and reported
with a certain degree of confidence, which must be greater than or equal to the lowest point in
the calibration curve. The laboratory shall establish the LLOQ at concentrations where both
quantitative and qualitative criteria can consistently be met (see Sec. 11.6). The laboratory
shall verify the LLOQ at least annually and whenever significant changes are made to the
preparation and/or analytical procedure, to demonstrate quantitation capability at lower analyte
concentration levels. The verification is performed by the preparation and/or analysis of an LCS
(or matrix spike) at 0.5 - 2 times the established LLOQ. Additional LLOQ verification may be
useful on a project-specific basis if a matrix is expected to contain significant interferences at
the LLOQ. This verification may be accomplished with either clean control material (e.g.,
reagent water, solvent blank, Ottawa sand, diatomaceous earth, etc.) or a representative
sample matrix, free of target compounds. Optimally, the LLOQ should be less than the desired
decision level or regulatory action level based on the stated DQOs.

9.9.1	LLOQ verification

9.9.1.1	The verification of LLOQs using spiked clean control material
represents a best-case scenario because it does not evaluate the potential matrix
effects of real-world samples. For the application of LLOQs on a project-specific
basis, with established DQOs, a representative matrix-specific LLOQ verification
may provide a more reliable estimate of the lower quantitation limit capabilities.

9.9.1.2	The LLOQ verification is prepared by spiking a clean control
material with the analyte(s) of interest at 0.5 - 2 times the LLOQ concentration
level(s). Alternatively, a representative sample matrix free of targets may be
spiked with the analytes of interest at 0.5 - 2 times the LLOQ concentration
levels. This LLOQ check is carried through the same preparation and analytical
procedures as environmental samples and other QC samples. LLOQ
verification samples must be independent from the ICAL used to calculate the
target analyte concentrations (i.e. not a recalculated calibration point). It is
recommended to verify the LLOQ on every instrument where data is reported.
However, at a minimum, the laboratory should rotate the verification among
similar analytical instruments such that all are included within three years.

9.9.1.3	Recovery of target analytes in the LLOQ verification should be
within established in-house limits or within other such project-specific acceptance
limits to demonstrate acceptable method performance at the LLOQ. Until the
laboratory has sufficient data to determine acceptance limits, the LCS criteria
±20% (i.e., lower limit minus 20% and upper limit plus 20%) may be used for the
LLOQ acceptance criteria. This practice acknowledges the potential for greater
uncertainty at the low end of the calibration curve. Practical, historically based
LLOQ acceptance criteria should be determined once sufficient data points have
been acquired.

9.9.2	Reporting concentrations below LLOQ - Concentrations that are below
the established LLOQ may still be reported. However, these analytes must be qualified
as estimated. The procedure for reporting analytes below the LLOQ should be
documented in the laboratory's SOP or in a project-specific plan. Analytes below the
LLOQ that are reported should meet most or all of the qualitative identification criteria in
Sec. 11.6.

9.10 It is recommended that the laboratory adopt additional QA practices for use with
this method. The specific practices that are most productive depend upon the needs of the

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laboratory and the nature of the samples. Whenever possible, the laboratory should analyze
standard reference materials and participate in relevant performance evaluation studies.

10.0 CALIBRATION AND STANDARDIZATION

See Sees. 11.3 and 11.4 for information on calibration and standardization.

11.0 PROCEDURE

11.1 Various alternative methods are provided for sample introduction. All ISs,
surrogates, and matrix spike compounds (when applicable) must be added to the samples
before introduction into the GC/MS system. Consult the sample introduction method for the
procedures by which to add such standards.

11.1.1	Direct injection - This includes: injection of an aqueous sample
containing a very high concentration of analytes; injection of aqueous concentrates from
Method 5031 (azeotropic distillation); and injection of a waste oil diluted with
hexadecane (Method 3585). Direct injection of aqueous samples (non-concentrated)
has very limited applications. Direct injection of aqueous samples is only used for the
determination of volatiles at the toxicity characteristic (TC) regulatory limits or at mg/L or
higher concentrations. Direct injection may also be used in conjunction with the test for
ignitability in aqueous samples (along with Methods 1010 and 1020), to determine if
alcohol is present at greater than 24%.

11.1.2	Purge and trap - This includes purge and trap for aqueous samples
(Method 5030) and purge and trap for solid samples (Method 5035). Method 5035 also
provides techniques for extraction of high concentration solid and oily waste samples by
methanol (and other water-miscible solvents) with subsequent purge and trap from an
aqueous matrix using Method 5030.

11.1.2.1	Traditionally, the purge and trap of aqueous samples is
performed at ambient temperature, while purging of soil/solid samples is
performed at 40 °C, to improve purging efficiency. Purging at a fixed
temperature slightly above ambient (e.g., 35 °C) may improve reproducibility
where ambient temperature is variable.

11.1.2.2	Aqueous and soil/solid samples may also be purged at higher
temperatures as long as all calibration standards, field samples, and associated
QC samples are purged at the same temperature, and the laboratory
demonstrates acceptable method performance for the project. Purging of
aqueous and soil/solid samples at elevated temperatures (i.e., 40 to 80 °C) may
improve the purging performance of more highly water soluble compounds which
have poor purging efficiencies at ambient temperatures.

11.1.3	Vacuum distillation - This technique may be used for the introduction of
VOCs from aqueous, solid, or tissue samples (Method 5032) into the GC/MS system
(see Method 8261).

11.1.4	Automated static headspace - This technique may be used for the
introduction of VOCs from aqueous and solid samples (Method 5021) into the GC/MS
system.

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11.1.5 Cartridge desorption - This technique may be used for the introduction
of VOCs from sorbent cartridges (Method 5041) used in the sampling of air. The
sorbent cartridges are from the volatile organics sampling train (VOST) or sampling
method for volatile organic compounds (SMVOC) (Method 0031).

11.2 Recommended chromatographic conditions are provided as examples based on
analyses performed in EPA laboratories and studies used to generate performance data for this
method. The actual conditions will depend on the compounds of interest, instrument, and
manufacturer's guidelines for the column selected. The maximum temperature of operation
should always be verified with the specific column manufacturer.

11.2.1 General conditions:

Injector temperature:
Transfer line temperature:

200 - 275 °C
200 - 300 °C

11.2.2 Direct split interface - The following are example conditions:

Carrier gas (He) flow rate:
Column:

Initial temperature:
Temperature program:

Inlet temperature:
Transfer line temperature:
Split ratio:

1.3 mL/min

60 m x 0.25 mm ID, 1.4 |jm DB-624

35 °C, hold for 3 min

6 °C /min to 100 °C,

12 °C /min to 180 °C,

20 °C /min to 200 °C, hold for 7 minutes

225 °C

230 °C

30:1

11.2.3 Split injection:

Carrier gas (He) flow rate:
Column:

Initial temperature:
Temperature program:

Inlet temperature:
Transfer line temperature:
Split ratio:

0.9 mL/min

20.0 m, 0.18 mm ID, 1.0 |jm DB-VRX

30 °C, hold for 3 min

10 °C/min to 100 °C,

20 °C/min to 240 °C; 1 minute hold

250 °C

250 °C

50:1

11.2.4 Split injection:

Carrier gas (He) flow rate:
Column:

Initial temperature:
Temperature program:

Split ratio:

0.7 mL/min

20 m x 0.18 mm x 1.0 |jm DB-624
40 °C, hold for 4 min
15 °C /min to 190 °C,

Hold for 1.5 min at 250 °C
35:1

11.2.5 Direct injection:

Carrier gas (He) flow rate:
Column:

Initial temperature:
Temperature program:

4 mL/min

70 m x 0.53 mm DB-624
40 °C, hold for 3 min
8 °C /min to 260 °C

11.2.6 Hydrogen carrier gas:

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Flow rate:
Column:

1 mL/min

40 m x 0.18 mm x 1-|jm film thickness
Rtx-VMS

30 °C, hold for 4 min
7 °C/min to 180 °C
200 °C
200 °C
70:1

Initial temperature:
Temperature program:
Injector temperature:
Transfer line temperature:
Split ratio:

11.3 ICAL - Establish the GC/MS operating conditions, using the following as
guidance:

Mass range:
Acquisition rate:

m/z of 35 - 270

Source temperature:
Ion trap only:

To result in at least five mass spectra across the peak (but

preferably ten or more)

According to manufacturer's specifications

Set axial modulation, manifold temperature, and emission current to
manufacturer's recommendations

11.3.1 The GC/MS system must produce mass spectra with sufficient mass
accuracy, mass resolution, and signal to be used for quantitative analysis of specific m/z
ratios of ions characteristic of the target analytes, surrogates, and ISs. Standardization of
MS performance also simplifies comparison of mass spectra generated on different
instruments, such as by searching unknown spectra against a commercially available
mass spectral library. A common reference compound used to demonstrate MS
performance for electron impact mass spectrometry is BFB. Table 3 provides BFB ion
ratio evaluation criteria. These criteria are only appropriate for electron impact mass
spectra acquired across the range of masses indicated in the table.

Acceptable system performance may also be demonstrated by meeting
manufacturer specifications for mass resolution, mass accuracy, and sensitivity using the
internal calibrant (e.g., Perfluorotributylamine, also known as PFTBA). Other reference
compounds may also be appropriate for demonstrating acceptable MS performance
depending on the system or conditions used for analysis (e.g., octafluoronaphthalene for
negative ion CI). Regardless of how MS performance is evaluated, system calibration
must not begin until performance criteria are met, and calibration standards and samples
must be analyzed under the same conditions. If CI, SIM or tandem MS is used, the
manufacturer's MS tuning criteria or one of the alternative procedures listed above may be
substituted for the BFB tune requirement.

11.3.1.1 In the absence of other recommendations on how to acquire
the mass spectrum of BFB, the following approach may be used:

Introduce BFB with the same technique to be used for analysis of
calibration standards and samples. Scale the mass of BFB introduced to
prevent high abundance masses from saturating the detector (e.g., <50 ng).

Once the data is acquired, either select the mass spectrum at the peak apex for
evaluation, or use an averaged mass spectrum (e.g., three highest abundance
spectra, across entire BFB peak). Background subtraction is allowed and
should only be used to eliminate column bleed or instrument background ions.
No part of the BFB peak or any other discrete peak should be subtracted. The
mass spectrum used for background subtraction may be either a single mass
spectrum or an average mass spectrum across a short time range acquired
within 20 seconds of the elution of BFB.

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11.3.1.2 Compare BFB mass intensities to the criteria in Table 3.
Alternatively, other documented ion ratio criteria may be used provided that
method performance is not adversely affected. If hydrogen is used as a carrier
gas, the Table 3 criterion for 96/95 m/z ratio of BFB will be difficult to achieve. A
relative abundance of 5 to 15% for 96/95 m/z is acceptable due to interactions
with the carrier gas and water vapor. The analyst is free to choose criteria that
are tighter than those included in this method or to use other documented criteria
provided they are used consistently throughout the ICAL, calibration verification,
and sample analyses.

NOTE: All subsequent standards, field samples, and QC samples associated
with this analysis must use identical MS instrument conditions with the
exception of SIM analysis. BFB may be analyzed in full scan mode while
standards, samples, and QC are analyzed in SIM.

NOTE: BFB tune checks are not appropriate for CI or tandem MS analysis using
SRM. However, the laboratory must demonstrate, prior to the ICAL, that
the MS system achieves mass accuracy and mass resolution criteria
specified by the instrument manufacturer for the PFTBA internal calibrant
or other appropriate chemical.

11.3.2	Set up the sample introduction system, and then prepare and analyze
calibration standards as outlined in the preparation method of choice (see Sec. 11.1).
ICAL standards must include at least five different standard concentrations for all target
analytes (see Sec. 7.11.1 and Method 8000). Surrogates may be calibrated either at
multiple concentrations in the ICAL or at a single concentration (i.e., constant amount
added to each calibration standard, as with IS). The base peak m/z of each target
analyte and IS is appropriate for use as the primary m/z for quantitation (see Table 1),
but another prominent m/z in the mass spectrum may also be used for quantitation
provided it is used consistently. If interferences are noted at the primary m/z, use an
alternate m/z. Calibration range, chromatographic performance, and extent of any
carryover will depend on the introduction technique, GC column and conditions, and the
tolerance of the sample introduction system and GC/MS to solvent, water, and other
introduced sample matrix components.

NOTE: LLOQs should be established at concentrations where both quantitative and
qualitative verifications can be consistently and reliably met (see Sees. 9.9 and
11.6). Target analyte peaks in the calibration standard at the LLOQ should be
visually inspected to ensure that peak signal is distinguishable from background
and to verify qualitative analyte identification.

11.3.3	Additional considerations for SIM and SRM analysis

SIM and SRM may be useful for applications requiring quantitation limits below
the normal range of electron impact quadrupole mass spectrometry, and both are
allowable options for this method. Using the primary m/z for quantitation and at least
one secondary m/z for confirmation, set up the collection groups based on their
chromatographic retention times. The selected m/z values should include any mass
defect noted in the target analyte mass spectra acquired on the instrument, usually less
than 0.2 amu. The dwell time for each ion may be automatically calculated by the
instrument software or may be calculated based on the peak widths of the analytes of
interest, the number of spectra needed to be acquired across each peak, and the
number of concurrent ions that need to be acquired in each segment. When fewer

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masses are monitored in each segment, the acquisition time for each mass can be
increased, thereby increasing the sensitivity of the system. The total cycle time for the
MS should be short enough that at least five, but preferably ten or more, spectra are
acquired per chromatographic peak.

When compounds are analyzed in SIM or SRM mode, the following best
practices are recommended:

• Monitor at least two ions for each target analyte, and use the mid-point of the
calibration curve to establish proper ion ratios for each compound. The ratios
of primary and secondary ions are the only qualitative tool available in SIM
and SRM runs (other than retention time) which increases their importance in
proper identification. When interferences are expected or observed in a given
matrix, acquiring multiple secondary ions may aid in qualitative identification.

• Verify that all monitored ions are correctly integrated in order to achieve
proper ion ratios. Update the primary/secondary ion ratios and reference
mass spectra after each ICAL using a mid-range ICAL standard.

11.3.4 Tabulate the response of the characteristic ions (see Table 1 for
suggested ions) against the concentration for each target analyte and each IS. Calculate
RFs for each target analyte relative to one of the ISs as follows:

A,xC,,

A„xC,

where:

As= Peak response of the analyte or surrogate
Ais= Peak response of the IS
Cs= Concentration of the analyte or surrogate
Cis= Concentration of the IS

11.3.4.1 Calculate the mean RF and the relative standard deviation
(RSD) of the RFs for each target analyte using the following equations.

where:

_

mean RF = RF = —	

n

RSD -iExlOO
RF

SD =

ECRF.-RF)3

i=l

RFi = RF for each of the calibration standards
RF = mean RF for each compound from the ICAL
n = Number of calibration standards, e.g., 5
SD = Standard deviation

n -1

11.3.4.2 The RSD should be <20% for each target analyte (see Sec.
11.3.5). Table 4 contains minimum RFs that may be used as guidance in
determining whether the system is behaving properly and as a check to see if
calibration standards are prepared correctly. Because the minimum RFs in
Table 4 were determined using specific ions and instrument conditions that may
vary, it is neither expected nor required that all analytes meet these minimum
RFs. The information in this table is provided as guidance only. The laboratory

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should establish procedures in its determinative SOP (e.g., laboratory
established minimum RFs, signal to noise (S/N) checks, etc.) to ensure that the
instrument is working properly and that calibration standards were correctly
prepared.

NOTE: For a target analyte whose RF <0.01 (response of peak is <1/100 the
response of the IS), it is recommended to increase its concentration in
relation to other analytes to make the response more comparable.

11.3.5 Linearity of target analytes - If the RSD of any target analyte is <20%,
then the RF is assumed to be constant over the calibration range, and the average RF
may be used for quantitation (Sec. 11.7.2).

11.3.5.1	If the RSD of any target analyte RF is >20%, refer to Sec. 11.5
of Method 8000 for additional calibration options (e.g., narrowing the calibration
range, changing calibration model, etc.), and apply one or more of these options
in order to meet the ICAL acceptance criteria. Alternatively, the affected target
analytes may be reported with an appropriate data qualifier, or the instrument
may be recalibrated.

NOTE: When the RSD for the RF calibration model is >20%, plotting and visual
inspection of a calibration curve can be a useful diagnostic tool. The
inspection may indicate analytical problems, including errors in standard
preparation, the presence of active sites in the chromatographic system,
analytes that exhibit poor chromatographic behavior, etc.

NOTE: Forcing the calibration model through the origin (for analytes that are

consistently detected in the laboratory reagent blanks) allows for a better
estimate of the background level of blank contaminants. An accurate
estimate of background contamination is necessary to set method
reporting limits for method analytes when blank levels are problematic.

11.3.5.2	If more than 10% of the compounds included with the ICAL
exceed the 20% RSD limit and do not meet the coefficient of determination
criterion (r2>0.99 or relative standard error (RSE) <20%) for alternate curve fits,
then the chromatographic system is considered too imprecise for analysis to
begin. Perform corrective actions as necessary (e.g., by adjusting moisture
control parameters, replacing the analytical trap, column, or moisture trap, or
adjusting desorb time), then repeat the calibration procedure beginning with Sec.
11.3. If compounds fail to meet these criteria, the associated concentrations
may still be determined but they must be reported as estimated. In order to
report non-detects, it must be demonstrated that there is adequate sensitivity to
detect the failed compounds at the applicable LLOQ. Refer to Method 8000 for
further discussion of RSE. Example RSE calculations can be found in
Reference 16.

11.3.5.3	Due to the large number of compounds that may be analyzed
by this method, it is likely that some compounds will not meet the acceptance
criteria described above. For these occasions, it is acknowledged that those
compounds that do not meet the criteria may not be critical to the specific project
and therefore data generated may be used as qualified data or estimated values
for screening purposes. The analyst should strive to place more emphasis on
meeting the calibration criteria for those compounds that are critical to the
project. The target analytes that do not meet the ICAL criteria should still be

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identified to the data user and the resulting data qualified appropriately, but it is
not necessary to meet criteria for compounds that will not be reported.

NOTE: It is considered inappropriate, once the calibration models have been
finalized, to select an alternate fit solely to pass the recommended QC
criteria for samples and associated QC on a case-by-case basis.

11.3.5.4 Calibration, especially when using linear regression models,
has the potential for a significant bias at the lower portion of the calibration curve.
The lowest calibration point should be recalculated (not reanalyzed) using the
final calibration curve in which this standard is used (i.e., re-fitting the response
from the low concentration calibration standard back into the curve). See
Method 8000 for additional details. The recalculated concentration of the low
calibration point, especially where linear regression fits are used, should be
within ±50% of the standard's true concentration, and the recalculated
concentrations of any calibration standards above the LLOQ should be within
±30%. Alternate criteria may be applied depending on the needs of the project.
However, those criteria should be clearly defined in a laboratory SOP or a
project-specific QAPP. Analytes which do not meet the re-fitting criteria should
be evaluated for corrective action. If a failure occurs in the low point and it is
equivalent to the LLOQ, the analyte should be reported as estimated near that
concentration or the LLOQ should be reestablished at a higher concentration
(See Method 8000 Sec. 11.5.4 for calculations).

11.3.6 ICV - Prior to analyzing samples, verify the ICAL using a standard
obtained from a second source to the calibration standard, if possible, such as a second
manufacturer or a manufacturer's batch prepared independently from the batch used for
calibration, if readily available. This standard should be prepared in the same clean
control matrix as that used for ICAL standards. Suggested acceptance criteria for the
analyte concentrations in this standard are 70 - 130% of the expected analyte
concentration(s). Alternative criteria may be appropriate based on project-specific
DQOs. Quantitative sample analyses should not proceed for those analytes that do not
meet the ICAL verification criteria. However, analyses may continue for those analytes
that do not meet the criteria with an understanding that these results could be used for
screening purposes and would be considered estimated values.

11.4 CCV - A CCV standard must be analyzed at the beginning of each twelve-hour
analytical period prior to any sample analysis.

NOTE: Tune checks (Sec. 11.3.1) are only required prior to ICAL.

11.4.1 The ICAL function (Sec. 11.3) for each compound of interest must be
verified once every twelve hours prior to sample analysis, using the same introduction
technique and conditions as used for analysis of ICAL standards and samples. This is
accomplished by analyzing a CCV standard (containing all the compounds that will be
reported) prepared from the same stock solutions or source materials used for ICAL
standards and at a concentration near the midpoint of the ICAL range. The results must
be compared against the most recent calibration curve and should meet the CCV
acceptance criteria provided in Sees. 11.4.3-11.4.5.

NOTE: This QC check may be omitted if samples are analyzed within twelve hours of
ICAL, and injection of the last ICAL standard may be used as the starting time
reference for evaluation.

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11.4.2	A blank must also be analyzed after the CCV standard and prior to any
samples in order to demonstrate that the total system (introduction device, transfer lines
and GC/MS system) is free from contaminants. Analytes of interest for the project that
did not meet the criteria should be identified to the data user and results qualified
appropriately. If the blank indicates contamination, then it may be appropriate to
analyze additional blanks to reduce any system contamination due to carryover from
standards or samples. See Sec. 9.5 for MB performance criteria. See Method 8000
for information regarding MB performance criteria.

11.4.3	CCV standard criteria

11.4.3.1	The calculated concentration or amount of each analyte of
interest in the CCV standard should fall within ±20% of the expected value.

NOTE: For the RF calibration model, % difference between the calculated RF of
an analyte in the calibration verification standard and the RFavg of that
analyte from the ICAL is the same value as % drift for calculated vs.
expected concentration. Refer to Method 8000 for guidance on
calculating % difference and % drift.

11.4.3.2	If the % difference or % drift for a compound is < 20%, then
the ICAL for that compound is assumed to be valid. Due to the large number of
compounds that may be analyzed by this method, it is likely that some
compounds will not meet this criterion. If the criterion is not met (i.e., greater
than 20% difference or drift) for more than 20% of the compounds included in the
ICAL (or more than 20% of those that will be reported), then corrective action
must be taken prior to analysis of samples. In these cases, the affected target
analytes may still be reported as non-detects in field samples if it can be
demonstrated that there was adequate sensitivity to detect the compound at the
applicable quantitation limit. For situations when the failed compound is
measured in field samples, the reported concentrations must be qualified
appropriately.

11.4.3.3	Problems similar to those listed under ICAL could affect the
ability to pass the CCV criteria. If the problem cannot be corrected by other
measures, a new ICAL must be generated. The calibration verification criteria
must be met before sample analysis begins.

11.4.4	IS RT - If the absolute RT for any IS changes by more than 30 seconds
from that in the mid-point standard level of the most recent ICAL sequence, then the
chromatographic system must be inspected for malfunctions and corrections must be
made, as required. When corrections are made, reanalysis of samples analyzed while
the system was malfunctioning is required.

11.4.5	IS responses - In order to demonstrate continued stability of the
measurement system after ICAL, IS responses in the CCVs must be evaluated by
comparing them to the responses of the same ISs in the ICAL standard(s). If the
response of an IS changes by more than a factor of 2 (50 - 200%) relative to the
response of that IS in the mid-point ICAL standard or the average of responses in the
suite of ICAL standards (as defined in the laboratory's SOP), then corrective actions
should be taken. These corrective actions may include but are not limited to replacing
and/or reanalyzing the CCV standard, or retuning the MS and re-calibrating the
instrument. When IS responses do not meet these criteria, system sensitivity may have

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been compromised, and sample reanalysis is recommended, especially if any action
limits for the project are near the LLOQ.

11.5 GC/MS analysis of samples

11.5.1	It is highly recommended that samples be screened to minimize
contamination of the GC/MS system or sample introduction device from unexpectedly
high concentrations of organic compounds. Some of the screening options available
utilizing SW-846 methods are:

-Screening solid samples for VOCs (Method 3815), automated headspace,

-GC/flame ionization detector (FID) (Methods 5021/8015), automated headspace,
-GC/photo ionization detector (PID)/electrolytic conductivity detector (ELCD) (Methods
5021/8021), or,

-Waste dilution - GC/PID/ELCD (Methods 3585/8021) using the same type of capillary
column.

When used only for screening purposes, the QC requirements in the methods above
may be reduced as appropriate. Sample screening is particularly important when
Method 8260 is used to achieve low quantitation levels.

11.5.2	Add appropriate volumes of the surrogates spiking solution and the IS
spiking solution to each field sample and all associated QC samples either manually or
by an autosampler to achieve the desired concentrations. The surrogates and ISs may
be mixed and added as a single spiking solution.

11.5.3	Add an aliquot of the target compounds spiking solution (Sec. 7.12) to
any sample aliquot(s) chosen for matrix spiking. Follow the same procedure in
preparing the LCS, adding the spike to the same clean control material used for
calibration standards preparation (e.g., reagent water, Ottawa sand, etc.). See Sec.
7.12 and Method 8000 for more guidance on the selection and preparation of the matrix
spike and the LCS.

11.5.4	Introduce field samples and associated QC samples to the GC/MS
under the same conditions used for analysis of ICAL standards. When screening
results indicate high levels of target analytes and/or interferences, or if analyte
concentrations are measured above the calibration range, prepare and analyze an
appropriate dilution of the sample(s), or choose a preparation method that is more
amenable to making dilutions (e.g., methanol extraction of solids instead of direct
aqueous partitioning). Dilutions should be targeted so the response of the major
constituents (previously saturated peaks) falls near the middle of the calibration range.

11.5.5	When the concentration of a compound in the sample is high enough to
result in significant carryover to subsequent samples (Sec. 9.5), this analysis should be
followed by at least one MB or instrument blank to demonstrate lack of carryover to the
proceeding field sample. If analysis of one or more blanks is not sufficient to return the
system to acceptable operating conditions, more extensive decontamination procedures
may be required, and subsequent recalibration may be necessary. Alternatively, when
analysis of a blank is not possible prior to the next sample, such as when an unattended
autosampler is employed, the analyst should review the results for at least the next
sample after the high-concentration sample. If analytes in the high-concentration
sample are not present in the subsequent field sample, then the lack of carryover has
been demonstrated.

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11.5.6 IS responses and RTs should be monitored in all field samples and
associated QC samples in order to provide sample-specific QA of proper analyte
introduction to the GC/MS system and to anticipate the need for system inspection
and/or maintenance. If the response of the primary m/z for any of the ISs in the field
samples or associated QC samples varies by more than a factor of two (-50% to
+100%) from that of the same IS in the mid-point ICAL standard, average of ICAL
standards, or most recently analyzed CCV standard (as defined in the laboratory's
SOP), corrective action should be taken. Any affected field samples and associated QC
samples should be re-analyzed, or the associated data should be qualified.

11.6 Analyte identification

11.6.1 Qualitative identification of each compound determined by this method
is based on RT and on comparison of the sample mass spectrum, after background
correction, with a reference mass spectrum. Compounds are identified as present
when the following criteria are met.

11.6.1.1	The intensities of the characteristic ions of a compound
maximize in the same mass spectra or in adjacent mass spectra.

11.6.1.2	The RT is within ±10 seconds of the RT for this analyte in the
midpoint ICAL standard or CCV standard analyzed at the beginning of the 12-
hour period (delta RT 0.17 minute), or within ±10 seconds relative to the shift of
the associated IS (delta RT of the IS ±10 seconds). Chromatograms should be
carefully inspected to minimize the occurrence of both false positive and false
negative results. If the RT for the IS has shifted, the sample should be
inspected for similar shifts for the associated target analytes. If RT drift is
significant, relative retention time (RRT) may be useful as an alternative to delta
retention times. See Section 11.4 of Method 8000 for additional information.

NOTE: Some analytes may have RT shifting that is much greater than the

associated IS (greater than ±10 seconds relative to the IS shift) and is still
the target analyte. In those cases, it may be more useful to compare the
delta RT with compounds that have similar chemistries to help identify the
target. Also, dilutions or spiked samples are recommended to help
determine the effects of matrix on the elution of the target and assist in
target identification.

11.6.1.3	The relative intensities of the characteristic ions should agree
within 30% of the intensities of these ions in the reference spectrum. For
example, for an ion with an abundance of 50% in the reference spectrum, the
corresponding abundance in a sample spectrum can range between 20% and
80%. The reference mass spectrum used for this comparison must be
generated by the laboratory using the conditions of this method (typically from a
calibration standard). Qualitative identification of sample mass spectra not
acquired in limited ion acquisition modes (i.e., SIM or SRM) may also be
supported by comparison to a reference library as described in Sec. 11.6.2.

11.6.1.4	Unresolved structural isomers with similar mass spectra are
identified as isomeric pairs. Isomers are considered resolved if the peaks are at
least 50% resolved (i.e., the height of the valley between two isomer peaks is <
50% of the average of the two peak heights, or 1-[valley height]/[average peak
height] is > 50%). The resolution should be verified on the mid-point
concentration of the ICAL as well as the laboratory-designated CCV level if

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closely eluting isomers are to be reported.

11.6.1.5	Identification is hampered when sample components are not
resolved chromatographically and produce mass spectra containing ions
contributed by more than one analyte. When gas chromatographic peaks
obviously represent more than one sample component (i.e., a broadened peak
with shoulder(s) or a valley between two or more maxima), appropriate selection
of analyte spectra and background spectra is important.

11.6.1.6	Examination of EICPs of appropriate ions can aid in the
selection of spectra, and in qualitative identification of compounds. When
analytes co-elute (i.e., only one chromatographic peak is apparent), the
identification criteria may be met, but each analyte spectrum will contain
extraneous ions contributed by the co-eluting compound.

11.6.2 For samples containing components not associated with the calibration
standards, a library search may be made for the purpose of tentative identification.
The necessity to perform this type of identification will be determined by the purpose of
the analyses being conducted. Data system library search routines should not use
normalization routines that would misrepresent the library or unknown spectra when
compared to each other. For example, the RCRA permit or waste delisting
requirements may require the reporting of non-target analytes. Only after visual
comparison of sample spectra with library search results may the analyst assign a
tentative identification. Use the following guidelines for making tentative identifications:

(1)	Major ions in the library reference spectrum (ions greater than 10% of the
most abundant ion) are present in the sample spectrum at similar relative
intensities.

(2)	The molecular ion in the library reference spectrum is present in the sample
spectrum. If the molecular ion is not present, carefully review library
matches in order to avoid misidentification.

(3)	Major ions present in the sample spectrum but not in the reference
spectrum are reviewed to determine whether they may be contributed by
co-eluting compounds.

(4)	Ions present in the reference spectrum but not in the sample mass spectra
are reviewed for unintended subtraction. Data system library reduction
programs can sometimes create these discrepancies.

(5)	Mass spectral library search algorithms typically assign a match factor to
the peak identity based on comparison of an unknown mass spectrum to
library spectra. For spectra meeting the above conditions, match factors
greater than 0.8 (80%) may be considered confirming evidence. Where a
known limitation in data collection is identified (e.g., the presence of an
incompletely resolved spectral interference), a lower match factor may be
considered confirmatory. For multiple library spectra with similar match
factors (e.g., for hydrocarbons with low abundance molecular ions, or
structural isomers), the tentative identification assigned to the unknown
may be better represented as a more generic structure (e.g., unknown
hydrocarbon, C4 benzene structural isomer). See Reference 15 for more
information.

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11.7 Quantitation

11.7.1	Once a compound has been identified, the quantitation of that
compound will be based on the integrated abundance from the EICP of the primary
characteristic ion. The IS used should be the one nearest the RT of that of a given
analyte.

11.7.1.1	Where the integration produced by the software is acceptable,
it is recommended to use it, because the software should produce more
consistent integrations. Manual integrations are necessary when the software
does not properly integrate peaks, such as when the baseline selection is
improper; the correct peak is missed; a co-elution is integrated; the peak is
partially integrated; etc. The analyst is responsible for ensuring that the
integration is correct whether performed by the software or done manually.

11.7.1.2	Manual integrations should not be substituted for proper
maintenance of the instrument or setup of the method (e.g., RT updates,
integration parameter files, etc.). The analyst should seek to minimize manual
integration by properly maintaining the instrument, updating RTs, and
configuring peak integration parameters.

11.7.2	If the RSD is 20% or less, then the RF calibration model is acceptable
for the ICAL (Sec. 11.3.4). See Method 8000 for the equations describing IS
calibration and either linear or non-linear calibrations.

11.7.3	Where applicable, the concentrations of any non-target analytes
identified in the sample (Sec. 11.6.2) may be estimated using the RF calibration model
formula, with the following modifications: The responses Ax and A-IS as defined in

Sec. 11.3.4 should be from the total ion chromatograms, and the RF for the non-target
analyte should be assumed to be 1. The resulting concentration should be clearly
identified as an estimate. Use the nearest IS free of interferences.

11.7.4	Structural isomers that produce very similar mass spectra may be
quantitated as individual isomers if they are sufficiently resolved. See Sec. 11.6.1.4.

11.7.5	Quantitation of multicomponent parameters such as gasoline-range
organics (GROs) and total petroleum hydrocarbons (TPH) using the Method 8260-
recommended IS quantitation technique is beyond the scope of this method. Typically,
analyses for these parameters are performed using a GC/FID or GC with a MS detector
capability that is available with Method 8015. However, it is acceptable to use the total
ion chromatogram that is generated from this method with external standard calibration
to quantitate such parameters. External standard calibration is recommended for these
applications in order to reduce the need to subtract area contributed by multiple non-
target peaks (such as the ISs) in the TPH chromatogram. See Sec. 11.4.2 in Method
8000 and Sec. 11.3 in Method 8015 for additional guidance.

12.0 DATA ANALYSIS AND CALCULATIONS

See Sec. 11.7 for information on data analysis and calculations.

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13.0 METHOD PERFORMANCE

13.1	Performance data and related information are provided in SW-846 methods only
as examples and guidance. The data do not represent required performance criteria for users
of the methods. Instead, performance criteria should be developed on a project-specific basis,
and the laboratory should establish in-house QC performance criteria for the application of this
method. These performance data are not intended to be and must not be used as absolute
QC acceptance criteria for purposes of laboratory accreditation.

13.2	This method has been tested using purge and trap (Method 5030) in a single
laboratory using spiked water. Using a wide-bore capillary column, water was spiked at
concentrations between 0.5 and 10 |jg/L. Single laboratory accuracy and precision data for
the method analytes are available at: http://www.epa.gov/hw-sw846/validated-test-method-
8260d-volatile-orqanic-compounds-qas-chromatoqraphvmass-spectrometrv.

13.3	Direct injection (Method 3585) has been used for the analysis of waste motor oil
samples using a wide-bore column. Single laboratory precision and accuracy data are
available at: http://www.epa.qov/hw-sw846/validated-test-method-8260d-volatile-orqanic-
compounds-qas-chromatoqraphvmass-spectrometrv for toxicity characteristic leaching
procedure (TCLP) volatiles in oil. The performance data were developed by analyzing seven
replicates each of new and used oil. The oils were spiked at the TCLP regulatory
concentrations for most analytes, with the exceptions of the alcohols, ketones, ethyl acetate
and chlorobenzene which are spiked at 5 ppm (well below the regulatory concentrations).

Prior to spiking, the new oil (i.e., a Society of Automotive Engineers (SAE) 30-weight motor oil)
was heated at 80 °C overnight to remove volatiles. The used oil (i.e., a mixture of used oil
drained from passenger automobiles) was not heated and was contaminated with 20 - 300 ppm
of benzene, toluene, ethylbenzene and xylene (BTEX) compounds and isobutanol. These
contaminants contributed to high recoveries of the BTEX compounds in the used oil. Therefore,
the data from the deuterated analogs of these analytes represent more typical recovery values.

13.4	Single laboratory accuracy and precision data were obtained for the Method
5035 analytes in three soil matrices: sand, a soil collected 10 feet below the surface of a
hazardous waste landfill, and a surface garden soil. Sample preparation was by Method 5035.
Each sample was fortified with the analytes at a concentration of 20 |jg/kg. These data are
available at: http://www.epa.qov/hw-sw846/validated-test-method-8260d-volatile-orqanic-
compounds-qas-chromatoqraphvmass-spectrometrv. All data were calculated using
fluorobenzene, added to the soil sample prior to methanol extraction, as the IS. Some of the
results were greater than 100% recovery, likely due to variance in IS response.

13.4.1	In general, the recoveries of the analytes from the sand matrix are the
highest, the hazardous waste landfill soil results are somewhat less, and the surface
garden soil recoveries are the lowest. This is due to the greater adsorptive capacity of
the garden soil. This illustrates the necessity of analyzing matrix spike samples to
assess the degree of matrix effects.

13.4.2	The recoveries of some of the gases, or very volatile compounds, such
as vinyl chloride, trichlorofluoromethane, and 1,1-dichloroethene, were somewhat
greater than 100%, likely due to the difficulty encountered in fortifying the soil with these
compounds, allowing an equilibration period, then extracting them with a high degree of
precision. The garden soil results (available at: http://www.epa.qov/hw-
sw846/validated-test-method-8260d-volatile-orqanic-compounds-qas-
chromatoqraphvmass-spectrometrv) also include high recoveries for some aromatic
compounds, including toluene, xylenes, and trimethylbenzenes. This is likely due to
high levels of contamination of the soil prior to sample collection.

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13.5	Performance data for non-purgeable volatiles using azeotropic distillation
(Method 5031) are included in Reference 9.

13.6	Performance data for volatiles prepared using vacuum distillation (Method 5032)
in soil, water, oil, and fish tissue matrices are included in Reference 11.

13.7	Single laboratory accuracy and precision data were obtained for the Method
5021 analytes in a garden soil matrix. Replicate samples were fortified with the analytes at a
concentration of 20 |jg/kg. These data are available at: http://www.epa.qov/hw-
sw846/validated-test-method-8260d-volatile-orqanic-compounds-qas-chromatoqraphvmass-
spectrometrv. The recommended ISs were selected because they generated the best
accuracy and precision data for the analytes in both types of soil.

13.7.1 Example LLOQs using Method 5021 are available at:
http://www.epa.gov/hw-sw846/validated-test-method-8260d-volatile-organic-
compounds-qas-chromatoqraphvmass-spectrometrv and were calculated from results of
seven replicate analyses of the sand matrix. Sand was chosen because it
demonstrated the least degree of matrix effect of the soils studied. These LLOQs were
calculated utilizing the procedure described in Chapter One and are intended to be a
general indication of the capabilities of the method.

13.8	The LLOQ for samples taken by Method 0040 and analyzed by Method 8260 is
estimated to be in the range of 0.03 to 0.9 parts-per-million (ppm). Data can be found at:
http://www.epa.qov/hw-sw846/validated-test-method-8260d-volatile-orqanic-compounds-qas-
chromatoqraphvmass-spectrometrv. Matrix effects may cause the individual compound
quantitation limits to be higher.

13.9	The recommended ISs with corresponding analytes assigned for quantitation
that are appropriate for Method 5041 are available at: http://www.epa.gov/hw-sw846/validated-
test-method-8260d-volatile-orqanic-compounds-qas-chromatoqraphvmass-spectrometrv.

14.0 POLLUTION PREVENTION

14.1	Pollution prevention encompasses any technique that reduces or eliminates the
quantity and/or toxicity of waste at the point of generation. Numerous opportunities for
pollution prevention exist in laboratory operations. The EPA has established a preferred
hierarchy of environmental management techniques that places pollution prevention as the
management option of first choice. Whenever feasible, laboratory personnel should use
pollution prevention techniques to address their waste generation. When wastes cannot be
feasibly reduced at the source, the Agency recommends recycling as the next best option.

14.2	For information about pollution prevention that may be applicable to laboratories
and research institutions consult:

http://www.acs.org/content/dam/acsorq/about/qovernance/committees/chemicalsafetv/publicatio
ns/less-is-better. pdf.

15.0 WASTE MANAGEMENT

The EPA requires that laboratory waste management practices be conducted consistent
with all applicable rules and regulations. The Agency urges laboratories to protect the air,
water, and land by minimizing and controlling all releases from hoods and bench operations,

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complying with the letter and spirit of any sewer discharge permits and regulations, and by
complying with all solid and hazardous waste regulations, particularly the hazardous waste
identification rules and land disposal restrictions. For further information on waste
management, consult The Waste Management Manual for Laboratory Personnel available at:
http://www.labsafetvinstitute.org/FreeDocs/WasteMqmt.pdf.

16.0 REFERENCES

1.	B. Prakash, A. D. Zaffiro, M. Zimmerman (Shaw Environmental, Inc.), D. J. Munch
(U.S. EPA, Office of Ground Water and Drinking Water) and B. V. Pepich (U.S.
EPA, Region 10 Laboratory), Measurement of Purgeable Organics Compounds in
Water by Capillary Column Gas Chromatography/Mass Spectrometer, Method
524.3, 2009.

2.	T. A. Bellar, J. J. Lichtenberg, Amer. Waterworks Assoc., 66(12), 739-744, 1974.

3.	T. A. Bellar, J. J. Lichtenberg, "Semi-Automated Headspace Analysis of Drinking
Waters and Industrial Waters for Purgeable Volatile Organic Compounds," in Van
Hall, Ed., Measurement of Organic Pollutants in Water and Wastewater, ASTM
STP686, pp 108-129, 1979.

4.	W. L. Budde, J. W. Eichelberger, "Performance Tests for the Evaluation of
Computerized Gas Chromatography/Mass Spectrometry Equipment and
Laboratories," U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory, Cincinnati, OH, EPA-600/4-79-020, April 1980.

5.	J. W. Eichelberger, L.E. Harris, W. L. Budde, "Reference Compound to Calibrate
Ion Abundance Measurement in Gas Chromatography-Mass Spectrometry
Systems "Analytical Chemistry 47, 995-1000, 1975.

6.	P. M. Jeffers, L. M. Ward, L. M. Woytowltch, and N. L. Wolfe, "Homogeneous
Hydrolysis Rate Constants for Selected Chlorinated Methanes, Ethanes, Ethenes,
and Propanes," Environmental Science and Technology, 23, 965-969, 1989.

7.	P. J. Marsden, C.L. Helms, B.N. Colby, "Analysis of Volatiles in Waste Oil," Report
for B. Lesnik, OSW/EPA under EPA contract 68-W9-001, June 1992.

8.	P. Flores, T. Bellar, "Determination of Volatile Organic Compounds in Soils Using
Equilibrium Headspace Analysis and Capillary Column Gas Chromatography/Mass
Spectrometry," U.S. Environmental Protection Agency, Office of Research and
Development, Environmental Monitoring Systems Laboratory, Cincinnati, OH,
December, 1992.

9.	M. L. Bruce, R. P. Lee, M. W. Stephens, "Concentration of Water Soluble Volatile
Organic Compounds from Aqueous Samples by Azeotropic Microdistillation,"
Environmental Science and Technology, 26, 160-163, 1992.

10.	P. H. Cramer, J. Wilner, J. S. Stanley, "Final Report: Method for Polar, Water
Soluble, Nonpurgeable Volatile Organics (VOCs)," For U.S. Environmental
Protection Agency, Environmental Monitoring Support Laboratory, EPA Contract
No. 68-C8-0041.

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11.	M. H. Hiatt, "Analysis of Fish and Sediment for Volatile Priority Pollutants,"
Analytical Chemistry, 53, 1541, 1981.

12.	Validation of the Volatile Organic Sampling Train (VOST) Protocol, Volumes I and
II, EPA/600/4-86-014A, January, 1986.

13.	Department of Defense Environmental Data Quality Workgroup (EMDQ), Data from
2012 Department of Defense Laboratory Control Sample Control Limit Study (2012
DOD LCS Study), July 15, 2013.

14.	EPA Contract Laboratory Organic Statement of Work (SOM02.3d),
http://www.epa.qov/sites/production/files/2015-10/documents/som23d.pdf.

15.	NIST/EPA/NIH Mass Spectral Library (NIST 14) and NIST Mass Spectral Search
Program (Version 2.2) User's Guide. National Institute of Standards and
Technology, June 2014..

16.	R. Burrows, Basic RSE calculator (version 2) and instructions, December 2016.

17.	US EPA Method 524.4, May 2013, EPA-815-R-13-002. Available at: nepis.epa.gov/

18.	ASTM Standard D4547, "Standard Guide for Sampling Waste and Soils for VOCs",
ASTM International, West Conshohocken, PA, 2015. Available atwww.astm.org.

17.0 TABLES, DIAGRAMS, FLOWCHARTS, AND VALIDATION DATA

The following pages contain the tables and figures referenced by this method.

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Table 1

CHARACTERISTIC MASSES (m/z) FOR PURGEABLE ORGANIC COMPOUNDS

Compound

Primary
Characteristic Ion

Secondary
Characteristic Ic

Acetone

58

43

Acetonitrile

41

40, 39

Acrolein (Propenal)

56

55, 58

Acrylonitrile

53

52, 51

Allyl alcohol

57

58, 39

Allyl chloride

76

41, 39, 78

Benzene

78

-

Benzyl chloride

91

126, 65, 128

Bromoacetone

136

43, 138, 93, 95

Bromobenzene

156

77, 158

Bromochloromethane

128

49, 130

Bromodichloromethane

83

85, 127

Bromoform

173

175, 254

Bromomethane

94

96

iso- Butanol

74

43

n-Butanol (1-Butanol, n-Butyl alcohol)

56

41

2-Butanone

72

43

n-Butylbenzene

91

92,134

sec-Butylbenzene

105

134

te/f-Butylbenzene

119

91, 134

Carbon disulfide

76

78

Carbon tetrachloride

117

119

Chloral hydrate

82

44, 84, 86, 111

Chloroacetonitrile

48

75

Chlorobenzene

112

77, 114

1-Chlorobutane

56

49

Chlorodibromomethane

129

208, 206

Chloroethane

64 (49*)

66 (51*)

2-Chloroethanol

49

44, 43, 51, 80

Bis(2-chloroethyl) sulfide

109

111, 158, 160

2-Chloroethyl vinyl ether

63

65, 106

Chloroform

83

85

Chloromethane

50 (49*)

52 (51*)

Chloroprene

53

88, 90, 51

3-Chloropropionitrile

54

49, 89, 91

2-Chlorotoluene

91

126

4-Chlorotoluene

91

126

1,2-Dibromo-3-chloropropane (DBCP)

75

155, 157

Dibromochloromethane

129

127

1,2-Dibromoethane (EDB, Ethylene
dibromide)

107

109, 188

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Compound

Primary Secondary
Characteristic Ion Characteristic lon(s)

Dibromomethane

93

95, 174

1,2-Dichlorobenzene

146

111,148

1,3-Dichlorobenzene

146

111,148

1,4-Dichlorobenzene

146

111,148

cis-1,4-Dichloro-2-butene

75

53, 77, 124, 89

trans-1,4-Dichloro-2-butene

53

88, 75

Dichlorodifluoromethane

85

87

1,1-Dichloroethane

63

65, 83

1,2-Dichloroethane

62

98

1,1-Dichloroethene (Vinylidene chloride)

96

61, 63

cis-1,2-Dichloroethene

96

61, 98

trans-^ ,2-Dichloroethene

96

61, 98

1,2-Dichloropropane

63

112

1,3-Dichloropropane

76

78

2,2-Dichloropropane

77

97

1,3-Dichloro-2-propanol

79

43, 81, 49

1,1-Dichloropropene

75

110, 77

c/s-1,3-Dichloropropene

75

77, 39

trans-1,3-Dichloropropene

75

77, 39

1,2,3,4-Diepoxybutane

55

57, 56

Diethyl ether

74

45, 59

1,4-Dioxane

88

58, 43, 57

Epichlorohydrin

57

49, 62, 51

Ethanol

31

45, 27, 46

Ethyl acetate

88

43, 45, 61

Ethyl benzene

91

106

Ethyl methacrylate

69

41, 99, 86, 114

Ethylene oxide

44

43, 42

Hexachlorobutadiene

225

223, 227

Hexachloroethane

201

166, 199, 203

2-Hexanone

43

58, 57, 100

2-Hydroxypropionitrile

44

43, 42, 53

lodomethane (Methyl iodide)

142

127, 141

Isobutyl alcohol (2-Methyl-1-propanol)

43

41, 42, 74

Isopropylbenzene

105

120

p-lsopropyltoluene

119

134, 91

Malononitrile

66

39, 65, 38

Methacrylonitrile

41

67, 39, 52, 66

Methyl acrylate

55

85

Methyl-f-butyl ether

73

57

Methyl iodide (lodomethane)

142

127, 141

Methyl methacrylate

69

41, 100, 39

4-Methyl-2-pentanone

100

43, 58, 85

Methylene chloride

84

86, 49

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Primary	Secondary

Characteristic Ion Characteristic lon(s)

Naphthalene

128

-

Nitrobenzene (NB)

123

51, 77

2-Nitropropane

46

-

Pentachlororethane

167

130, 132, 165, 169

2-Picoline (2-Methylpyridine)

93

66, 92, 78

Propargyl alcohol

55

39, 38, 53

(3-Propiolactone

42

43, 44

Propionitrile (Ethyl cyanide)

54

52, 55, 40

n-Propylamine

59

41, 39

n-Propylbenzene

91

120

Pyridine

79

52

Styrene

104

78

1,1,1,2-T etrachloroethane

131

133, 119

1,1,2,2-T etrachloroethane

83

131, 85

Tetrachloroethene

164

129, 131, 166

Toluene

92

91

1,2,3-T richlorobenzene

180

182, 145

1,2,4-T richlorobenzene

180

182, 145

1,1,1-Trichloroethane

97

99, 61

1,1,2-T richloroethane

83

97, 85

Trichlororethene

95

97, 130, 132

T richlorofluoromethane

101

103

1,2,3-T richloropropane

75

77

1,2,4-T rimethylbenzene

105

120

1,3,5-T rimethylbenzene

105

120

Vinyl acetate

43

86

Vinyl chloride

62

64

o-Xylene

106

91

m-Xylene

106

91

p-Xylene

106

91

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Table 1A
Internal Standards/Surrogates

Compound

Primary Characteristic
Ion

Secondary

Characteristic

lon(s)

Benzene-ds

84

83

Bromobenzene-ds

82

162

Bromochloromethane-ck

51

131

4-Bromofluorobenzene

95

174, 176

Chlorobenzene-ds

117

-

Chloroform-dy

84

-

Dibromofluoromethane

113

-

1,2-Dichlorobenzene-d4

152

115, 150

1,4-Dichlorobenzene-d4

152

115, 150

Dichloroethane-d*

102

-

1,4-Difluorobenzene

114

-

Fluorobenzene

96

77

Pentafluorobenzene

168

-

Toluene-dg

98

-

1,1,2-T richloroethane-d3

100

-

Characteristic ion for an ion trap MS (to be used when ion-molecule reactions are observed).

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Table 2

2012 DEPARTMENT OF DEFENSE LABORATORY CONTROL SAMPLE

CONTROL LIMIT STUDY

Relative standard deviation of recoveries by analyte for compounds where the number of
replicates, N was greater than 20 (average for all analytes: Recovery = 97%, 12% RSD).

Analyte Name

CAS#

Water RSD

Solid RSD

Acetaldehyde

75-07-0

66%

52%

Acetone

67-64-1

20%

21%

Acetonitrile

75-05-8

16%

15%

Acrolein [Propenal]

107-02-8

20%

18%

Acrylonitrile

107-13-1

12%

11%

Allyl chloride

107-05-1

11%

11%

tert-Amyl ethyl ether

919-94-8

10%

10%

tertiary-Amyl methyl ether (tame)

994-05-8

6%

10%

Benzene

71-43-2

7%

7%

Benzyl chloride

100-44-7

18%

10%

bis(2-Chloroisopropyl) ether

39638-32-9

12%

NA

Bromobenzene

108-86-1

7%

7%

Bromochloromethane

74-97-5

7%

8%

Bromodichloromethane

75-27-4

8%

8%

4-Bromofluorobenzene

460-00-4

5%

7%

Bromoform

75-25-2

11%

11%

Bromomethane

74-83-9

15%

15%

1,3-Butadiene

106-99-0

19%

10%

2-Butanone [MEK]

78-93-3

15%

16%

n-Butyl acetate

123-86-4

10%

12%

Butyl acrylate

141-32-2

72%

NA

n-Butyl alcohol

71-36-3

13%

14%

sec-Butyl alcohol

78-92-2

NA

17%

tert-Butyl alcohol

75-65-0

10%

11%

tert-Butyl formate

762-75-4

11%

NA

sec-Butylbenzene

135-98-8

8%

9%

tert-Butylbenzene

98-06-6

8%

9%

Carbon disulfide

75-15-0

12%

12%

Carbon tetrachloride

56-23-5

10%

11%

Chlorobenzene

108-90-7

6%

7%

2-Chloro-1,3-butadiene

126-99-8

12%

11%

Chlorobutane

109-69-3

NA

8%

Chlorodibromomethane

124-48-1

9%

9%

Chlorodifluoromethane

75-45-6

18%

19%

Chloroethane

75-00-3

13%

13%

2-Chloroethyl vinyl ether

110-75-8

16%

18%

Chloroform

67-66-3

7%

8%

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Analyte Name

CAS#

Water RSD Solid RSD

1-Chlorohexane

544-10-5

8%

10%

Chloromethane

74-87-3

16%

15%

1-Chloropropane

540-54-5

10%

8%

2-Chloropropane

75-29-6

12%

9%

2-Chlorotoluene

95-49-8

7%

8%

4-Chlorotoluene

106-43-4

7%

9%

2-Chloro-1,1,1 -trifluoroethane

75-88-7

8%

7%

Chlorotrifluoroethene

79-38-9

22%

24%

Cyclohexane

110-82-7

10%

11%

Cyclohexanone

108-94-1

42%

22%

1,2-Dibromo-3-chloropropane

96-12-8

12%

12%

1,2-Dibromoethane (EDB, Ethylene

106-93-4

7%

7%

dibromide)

Dibromofluoromethane

1868-53-7

7%

7%

Dibromomethane

74-95-3

7%

8%

1,2-Dichlorobenzene

95-50-1

7%

7%

1,3-Dichlorobenzene

541-73-1

7%

8%

1,4-Dichlorobenzene

106-46-7

7%

8%

cis-1,4-Dichloro-2-butene

1476-11-5

15%

12%

trans-1,4-Dichloro-2-butene

110-57-6

18%

13%

Dichlorodifluoromethane [Freon-12]

75-71-8

22%

23%

1,1-Dichloroethane

75-34-3

8%

8%

1,2-Dichloroethane

107-06-2

9%

9%

1,1-Dichloroethene (Vinylidene chloride)

75-35-4

10%

10%

1,2-Dichloroethene

540-59-0

7%

7%

cis-1,2-Dichloroethene

156-59-2

8%

8%

trans-1,2-Dichloroethene

156-60-5

8%

9%

Dichlorofluoromethane

75-43-4

10%

18%

1,2-Dichloropropane

78-87-5

7%

8%

1,3-Dichloropropane

142-28-9

7%

7%

2,2-Dichloropropane

594-20-7

13%

11%

1,1-Dichloropropene

563-58-6

8%

8%

1,3-Dichloropropene

542-75-6

8%

8%

cis-1,3-Dichloropropene

10061-01-5

8%

9%

trans-1,3-Dichloropropene

10061-02-6

9%

10%

1,2-Dichloro-1,1,2,2-tetrafluoroethane

76-14-2

16%

20%

1,2-Dichlorotrifluoroethane [Freon 123a]

354-23-4

11%

12%

Diethyl ether

60-29-7

10%

10%

Diethylbenzene (total)

25340-17-4

6%

6%

1,2-Diethylbenzene

135-01-3

6%

5%

1,3-Diethylbenzene

141-93-5

6%

6%

1,4-Diethylbenzene

105-05-5

6%

6%

Diisopropyl ether

108-20-3

11%

10%

Dimethyl ether

115-10-6

11%

NA

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Analyte Name

CAS#

Water RSD

Solid RSD

3,3-Dimethyl-1-butanol

624-95-3

15%

14%

Dimethyldisulfide

624-92-0

15%

9%

1,4-Dioxane

123-91-1

14%

14%

Epichlorohydrin

106-89-8

13%

14%

Ethanol

64-17-5

17%

19%

Ethyl acetate

141-78-6

14%

15%

Ethyl acrylate

140-88-5

38%

49%

Ethyl methacrylate

97-63-2

9%

10%

Ethyl tert-butyl ether

637-92-3

10%

9%

Ethylbenzene

100-41-4

7%

8%

2-Ethyl-1-hexanol

104-76-7

21%

25%

4-Ethyltoluene

622-96-8

14%

13%

Fluorobenzene

462-06-6

6%

6%

Furan

110-00-9

16%

NA

Heptane

142-82-5

16%

16%

Hexachlorobutadiene

87-68-3

11%

13%

Hexachloroethane

67-72-1

10%

10%

Hexane

110-54-3

17%

17%

2-Hexanone

591-78-6

14%

16%

lodomethane (Methyl iodide)

74-88-4

10%

10%

Isoamyl alcohol

123-51-3

14%

14%

Isobutyl alcohol

78-83-1

12%

13%

Isoprene

78-79-5

9%

18%

Isopropyl acetate [Acetic acid]

108-21-4

12%

13%

Isopropylbenzene

98-82-8

10%

11%

p-lsopropyltoluene [p-Cymene]

99-87-6

8%

9%

Methacrylonitrile

126-98-7

12%

11%

Methyl acetate

79-20-9

14%

15%

Methyl acrylate

96-33-3

12%

11%

Methyl methacrylate

80-62-6

10%

12%

Methyl sulfide

75-18-3

13%

12%

Methyl tert-butyl ether [MTBE]

1634-04-4

9%

9%

Methylcyclohexane

108-87-2

10%

11%

Methylene chloride

75-09-2

8%

10%

2-Methylnaphthalene

91-57-6

26%

27%

4-Methyl-2-pentanol

108-11-2

15%

NA

4-Methyl-2-pentanone [MIBK]

108-10-1

11%

12%

Methylstyrene

25013-15-4

8%

8%

Naphthalene

91-20-3

12%

12%

2-Nitropropane

79-46-9

16%

17%

Pentachloroethane

76-01-7

11%

11%

Pentane

109-66-0

26%

25%

2-Pentanone

107-87-9

15%

NA

SW-846 Update VI

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Analyte Name

CAS#

Water RSD

Solid RSD

2-Propanol [Isopropyl alcohol]

67-63-0

15%

13%

Propionitrile [Ethyl cyanide]

107-12-0

12%

11%

n-Propyl acetate

109-60-4

8%

16%

n-Propylbenzene

103-65-1

8%

9%

Styrene

100-42-5

8%

8%

1,1,1,2-T etrachloroethane

630-20-6

8%

8%

1,1,2,2-T etrachloroethane

79-34-5

9%

9%

Tetrachloroethene

127-18-4

9%

9%

Tetrahydrofuran

109-99-9

13%

13%

1,2,4,5-Tetramethylbenzene

95-93-2

11%

11%

Toluene

108-88-3

7%

7%

1,2,3-T richlorobenzene

87-61-6

10%

11%

1,2,4-T richlorobenzene

120-82-1

10%

11%

1,3,5-T richlorobenzene

108-70-3

9%

10%

2,3,4-T richlorobutene

2431-50-7

4%

NA

1,1,1-Trichloroethane

71-55-6

9%

9%

1,1,2-T richloroethane

79-00-5

7%

7%

Trichloroethene (Trichloroethylene)

79-01-6

7%

8%

Trichlorofluoromethane [Freon-11]

75-69-4

12%

13%

1,2,3-T richloropropane

96-18-4

8%

9%

1,1,1 -T richlorotrifluoroethane

354-58-5

9%

7%

Trifluorotoluene

98-08-8

6%

9%

1,1,2-Trifluoro-1,2,2-trichloroethane [Freon-
113]

76-13-1

11%

12%

1,2,3-T rimethylbenzene

526-73-8

6%

6%

1,2,4-T rimethylbenzene

95-63-6

8%

8%

1,3,5-T rimethylbenzene

108-67-8

8%

9%

2,2,4-Trimethylpentane [Isooctane]

540-84-1

13%

14%

Vinyl acetate

108-05-4

15%

17%

Vinyl bromide

593-60-2

13%

7%

Vinyl chloride

75-01-4

14%

14%

Xylenes [total]

1330-20-7

7%

8%

m/p-Xylene [3/4-Xylene]

179601-23-1

7%

8%

o-Xylene

95-47-6

7%

8%

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8260D - 41

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Table 3

4-BROMOFLUOROBENZENE (BFB) SUGGESTED CRITERIA*

m/z

Intensity (relative abundance)

95

50-200% of mass 174

96

5 to 9% of m/z 95
(5 to 15% when using H2 carrier)

173

<2% of m/z 174

174

50-200% of mass 95

175

5 to 9% of m/z 174

176

95 to 105% of m/z 174

177

5 to 10% of m/z 176

* Criteria based on EPA Method 524.4 (Reference 17), with modified m/z 95 and m/z
174 abundance criteria

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Table 4

GUIDANCE RESPONSE FACTORS CRITERIA FROM EPA CONTRACT

LABORATORY PROGRAM

Analyte

RF

Acetone

0.01

Benzene

0.2

Bromochloromethane

0.1

Bromodichloromethane

0.3

Bromoform

0.1

Bromomethane

0.01

2-Butanone

0.01

Carbon disulfide

0.1

Carbon tetrachloride

0.1

Chlorobenzene

0.4

Chloroethane

0.01

Chloroform

0.3

Chloromethane

0.01

Cyclohexane

0.01

Dibromochloromethane

0.2

1,2-Dibromo-3-chloropropane

0.01

1,2-Dibromoethane (EDB, Ethylene dibromide)

0.2

1,2-Dichlorobenzene

0.6

1,3-Dichlorobenzene

0.5

1,4-Dichlorobenzene

0.6

Dichlorodifluoromethane

0.01

1,1-Dichloroethane

0.3

1,2-Dichloroethane

0.07

1,1-Dichloroethene (Vinylidene chloride)

0.06

cis-1,2-Dichloroethene

0.2

trans-1,2-Dichloroethene

0.1

1,2-Dichloropropane

0.2

cis-1,3-Dichloropropene

0.3

trans-1,3-Dichloropropene

0.3

Ethylbenzene

0.4

2-Hexanone

0.01

Isopropylbenzene

0.4

Methyl acetate

0.01

4-Methyl-2-pentanone

0.03

Methyl tert-butyl ether (MTBE)

0.1

Methylcyclohexane

0.05

Methylene chloride

0.01

Styrene

0.2

1,1,2,2-T etrachloroethane

0.2

Tetrachloroethene

0.1

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Analyte

RF

Toluene

0.3

1,2,3-T richlorobenzene

0.4

1,2,4-T richlorobenzene

0.4

1,1,1-Trichloroethane

0.05

1,1,2-T richloroethane

0.2

1,1,2-T richloro-1,2,2-trifluoroethane

0.05

Trichloroethene (Trichloroethylene)

0.2

T richlorofluoromethane

0.01

Vinyl chloride

0.01

m,p-Xylene

0.2

o-Xylene

0.2

These response factors are provided as guidance only and are not intended to be a
requirement. See Appendix B for additional information.

Table 5

RECOMMENDED QUANTITY OF EXTRACT FOR ANALYSIS OF HIGH
CONCENTRATION SAMPLES

Approximate Concentration Range

	(Mg/kg)	

Volume of Extract3

500- 10,000 100 |jL
1,000-20,000 50 (jL
5,000- 100,000 10 mL
	25,000 - 500,000	100 |jL of 1/50 dilution13

Calculate appropriate dilution factor for concentrations exceeding this table.

a The volume of solvent added to 5 mL of water being purged should be kept constant. Therefore, add to the 5-mL
syringe whatever volume of solvent is necessary to maintain a volume of 100 |jL added to the syringe.

b Dilute an aliquot of the solvent extract and then take 100 |jL for analysis.

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Table 6

VOLATILE INTERNAL STANDARDS WITH CORRESPONDING ANALYTES
ASSIGNED FOR QUANTITATION

FLUOROBENZENE

CHLOROBENZENE-ds

1,4-DICHLOROBENZENE-d4

Acetone

Benzene

p-Bromofluorobenzene

Acrylonitrile

Bromodichloromethane

(surrogate)

Bromochloromethane

Carbon tetrachloride

Bromoform

Bromomethane

Chlorobenzene

n-Butylbenzene

2-Butanone

Cyclohexane

sec-Butylbenzene

Carbon disulfide

Dibromochloromethane

f-Butylbenzene

Chloroethane

1,2-Dibromoethane (EDB, Ethylene

1,2-Dibromo-3-chloropropane

Chloroform

dibromide)

1,2-Dichlorobenzene

Chloromethane

1,2-Dichloropropane

1,3-Dichlorobenzene

Dichlorodifluoromethane

cis-1,3-Dichloropropene

1,4-Dichlorobenzene

1,1-Dichloroethane

trans-1,3-Dichloropropene

1,2-Dichlorobenzene-d4 (surrogate)

1,2-Dichloroethane

Ethylbenzene

Hexachlorobutadiene

1,2-Dichloroethane-d4

2-Hexanone

Isopropylbenzene

(surrogate)

Methyl cyclohexane

Isopropyltoluene

1,1-Dichloroethene

4-Methyl-2-pentanone

Naphthalene

(Vinylidene chloride)

Styrene

n-Propylbenzene

cis-1,2-Dichloroethene

1,1,1,2-T etrachloroethane

1,2,3-T richloropropane

trans-1,2-Dichloroethene

1,1,2,2-T etrachloroethane

1,2,4-T rimethylbenzene

1,4-Difluorobenzene
(surrogate)

Freon 113

Tetrachloroethene
1,1,1-Trichloroethane

1,3,5-T rimethylbenzene
1,2,3-T richlorobenzene

1,1,2-T richloroethane

1,2,4-T richlorobenzene

Methyl acetate

Trichloroethene (Trichloroethylene)

Methylene chloride

Toluene



Methyl-f-butyl ether (MTBE)

Toluene-dg
(surrogate)



T richlorofluoromethane



Vinyl chloride

m- + p-Xylene
o-Xylene



Please note that this list is not exhaustive of all compounds found in the table in Sec 1.1 and are
suggested IS associations only.

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Table 7

SUMMARY OF QC CRITERIA FOR USE WITH 8260D

Quality Control Type

Minimum frequency

Specification

Suggested Acceptance Criteria

Instrument
performance check
(Sees. 9.3.1, 11.3.1)

Prior to initial calibration

Must be
verified prior
to initial
calibration

Meet ion ratio criteria for reference
compound: 4-Bromofluorobenzene
(Table 3), or alternative documented
criteria

Initial Calibration
(ICAL)
(Sees. 9.3.2,
11.3.2-11.3.5)

Prior to analyzing
samples, and as needed
if continuing
performance criteria
cannot be met

5	points
minimum for
RF and linear
regressions,

6	points
minimum for
quadratic
regressions;

>90% of

reported

target

analytes

meet initial

calibration

criteria

For average response factor (RF)
calibration model: <20% RSD of RFs;

For linear or quadratic regression
model: R>0.995, R2>0.99;

Independent of calibration model:
Lower standard (LLOQ) recalculation
(refit) is within ±50% of true value;
Other standards > LLOQ are within
±30% of true value;

Or, relative standard error (RSE)
<20% (Refer to Method 8000 and
Reference 16 for calculation)

See Method 8000 for additional
criteria.





Prepared
from different



ICAL Verification (ICV)
(Sees. 9.3.2, 11.3.6)

After each initial
calibration, and prior to
analyzing samples

source of
target

analytes than
initial

calibration
standards

Calculated concentrations of target
analytes are within ±30% of expected
value

Continuing Calibration
Verification (CCV)
(Sees. 9.3.3, 11.4)

Once every 12 hours

>80% of
target
analytes

meet
continuing
calibration
verification
criteria

Target analytes and surrogates are
<20% difference or drift; internal
standard responses are within 50%
to 200% of mid-point of ICAL or
average of ICAL internal standards;
and retention times for internal
standards have not shifted > 30
seconds relative to ICAL

Blanks
(Sees. 9.5, 9.6.1)

One method blank per
preparation batch of 20
or fewer samples;
instrument blanks as
needed

NA

Target analyte concentrations in
blanks are <1/2 LLOQ, or < 10% of
concentration in field samples

Laboratory Control
Standard (LCS)
(Sec 9.6.2)

One per preparation
batch of 20 or fewer
samples

NA

Meets recovery criteria (CCV criteria
may be used if LCS and CCV are
identical)

SW-846 Update VI

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Quality Control Type

Minimum frequency

Specification

Suggested Acceptance Criteria

Duplicates and Matrix
Spikes
(Sees. 9.6.3)

A duplicate and matrix
spike, or matrix
spike/matrix spike
duplicate per preparation
of 20 or fewer samples
(not required per batch)

NA

Meets performance-based or project-
defined recovery criteria and for
relative % difference between
sample and laboratory duplicate or
matrix spike/matrix spike duplicate;

Surrogates
(Sees. 9.7)

Added to each sample

NA

Meets performance-based recovery
criteria established by the laboratory
or criteria chosen for the project

Internal Standards
(Sees. 9.8, 11.5.6)

Added to each sample

NA

Internal standard response is within
50-200% of the response of the
same internal standard in the
midpoint ICAL standard (or average
of ICAL) or most recent CCV







RT in sample is within ±10 sec of RT
in midpoint ICAL or CCV standard

Qualitative Analyte
Identification
(Sec. 11.6.1)

Each target analyte

NA

Characteristic ion(s) are within ±30%
of expected ion ratio in reference
spectrum; or, match to reference
library spectra >0.8 (only for full
mass range acquisition modes)

SW-846 Update VI

8260D - 47

Revision 4
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Figure 1

EXAMPLE GAS CHROMATOGRAM OF VOLATILE ORGANICS a

Abi

TIC: kw022117a02,DWafa.ms

700000

850000

800000

550000

500000

450000

400000

350000

300000-

250000

200000

150000

100000

50000

Time-* 4,00 6 00 8.00 10.00 12.00 14.00 16.00 18,00 20.00 22.00 24.00 28.00 281

Figure

Courtesy of EPA Region 10.

SW-846 Update VI

8260D - 48

Revision 4
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Figure 2

EXAMPLE GAS CHROMATOGRAM OF VOLATILE ORGANICS a

an
ill
mi

MI
Mil

in;

Tiic
lit

IT!

Mi"
III
11'

hi;

i#i;

hi:

Hi;

a Courtesy of EPA Region 5

SW-846 Update VI	8260D - 49	Revision 4

February 2017

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Appendix A: Summary of Revisions to Method 8260C (From Revision 3, August 2006)

1.	Throughout the document the overall method formatting was updated for consistency with
new SW-846 methods style guidance. The term mass was replaced with m/z to reflect
what is actually being measured by the detector. Area or height was replaced with
response. Language was added allowing the use of hydrogen gas as a carrier.

2.	Section 1: The table (Sec. 1.1) was updated with new designations for performance {/, *,
etc.). Definitions of these symbols (Sec. 1.1) and expanded descriptions of compounds
with known performance issues (Sec. 1.3) was added. Trichlorotrifluoroethane was split
into two isomers: 1,1,2-Trichlorotrifluoroethane and 1,1,1-Trichlorotrifluoroethane.

3.	Section 5: The designation MSDS (material safety data sheets) was updated to SDS
(safety data sheets), as that is the correct term in the Global Harmonization System
(GHS). A safety note was added regarding hydrogen.

4.	Section 6: All vendors and product names were removed and replaced with generic terms
(Sec. 6.2.1). MS acquisition rate was changed to minimum number of spectra per peak
(Sec. 6.2.2.1). Subsections for tandem MS (Sec. 6.2.2.3) and SIM/CI (Sec. 6.2.2.4) were
added.

5.	Section 7: A paragraph was added about performing ICV with an alternate source (Sec.
7.11.3). Language was added regarding carrier gases to the reagents and standards
section (Sec. 7.14).

6.	Section 9: This section was completely updated and reorganized. New language and
references were added from Method 8000. Sections on IDP (Sec. 9.4), blank language
(Sees. 9.5 through 9.5.4), and LLOQ (Sec. 9.9) were updated and expanded. Significant
revisions/additions were made to the blank section adding clarifying information about
concentrations allowed in blanks (one half LLOQ), how blank concentration relates to
sample concentration (<1/10), and some guidance for qualifying data. Information was
added about the required frequency of LLOQ check standards (Sec. 9.9.1.2).

7.	Section 11: This section was updated and reorganized. The chromatographic conditions
were updated for commonly used columns (Sees. 11.2.1 through 11.2.5) and a set of
conditions for hydrogen carrier gas was added (Sec. 11.2.6). The tuning criteria were
updated for BFB for full scan analysis (Sec. 11.3 and Table 3), as well as other options,
including SIM and/or CI analysis. Two notes were added (Sec. 11.3.1.2) regarding when
each type of tune verification is appropriate. Tune verification frequency was also
updated from once every 12 hours to once prior to ICAL. SIM and SRM guidance were
updated (Sec. 11.3.3). A note was added regarding initial calibration curve fit when blank
contamination is present and additional options for evaluation of calibration fit (Sec.

11.3.5). Updated language on ICV standards was added (Sec. 11.3.6). Clarified
calibration verification frequency to allow for last initial calibration standard to be the start
of 12-hour clock for samples analyzed after initial calibration (Sec. 11.4.1). Clarified that
a blank is required after initial calibration and continuing calibration verification. Clarified
that monitoring of ISs in CCVs is required. IS RT is now defined in absolute terms only
(Sec. 11.4.4). Options to use mass spectral library searches to support qualitative
identification were added (Sec. 11.6.1.3). Calculations for verifying chromatographic
peak resolution were updated (Sec. 11.6.1.4). TIC interpretation language was revised
(Sec. 11.6.2). Language was added regarding the analysis of TPH and GRO
multicomponent mixes via total ion chromatogram (Sec. 11.7.5).

8.	Section 13: Performance data listed previously in tables at the end of 8260C can now be

SW-846 Update VI

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found at: http://www.epa.qov/hw-sw846/validated-test-method-8260d-volatile-orqanic-
compounds-qas-chromatoqraphvmass-spectrometrv.

9.	Sections 14 and 15: The links to the listed safety documents were updated and replaced
with the following links:

a.	http://www.acs.orq/content/dam/acsorq/about/qovernance/committees/chemicalsafet
v/publications/less-is-better.pdf and

b.	http://www.labsafetvinstitute.org/FreeDocs/WasteMqmt.pdf

10.	Section 16.0: Updated Reference 1 and added Reference 13 for DOD data used to
populate Table 2.

11.	Table 1: New analytes with suggested ions were added.

12.	Table 2: LLOQ limits were removed and replaced with 2012 DOD study data.

13.	Table 3: BFB criteria were updated with new criteria from Method 524.3.

14.	Table 4: Min RF table was renamed as guidance and a caution statement was added
below the table. Compounds are listed alphabetically by compound name.

15.	Table 6: Suggested IS associations were added. Compounds are listed alphabetically by
compound name.

16.	Table 7: Suggested QC criteria for use with Method 8260D were added.

17.	Appendix B was added discussing the use of hydrogen as a carrier gas.

18.	The SW-846 Workgroup conducted a thorough review of the use of the words "must" and
"should" with regards to the requirements for the frequency and type of QC samples and
the associated acceptance criteria for them in this method.

19.	A table of contents was added and all graphics and tables in this method were updated be
508 complaint.

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Appendix B: Guidance for Using Hydrogen Carrier Gas

B1.0 Guidance for Using Hydrogen Carrier Gas

B1.1 Hydrogen is an acceptable carrier gas to use for this analysis. However, the
following modifications may be needed to make the analysis comparable to helium carrier gas:

B1.1.1 It is recommended that the highest purity (99.999% or better) hydrogen
gas be used, such as from a generator or from high purity cylinders that will have
minimal interferences present (e.g., hydrocarbons and water). Use of stainless steel
tubing instead of copper tubing may increase the longevity of gas lines as older copper
lines may become brittle over time with the use of hydrogen. MS ion source materials
should be designed and approved for use with hydrogen. Contact the manufacturer of
the MS to confirm the ion source is compatible with hydrogen.

Additionally, the pressure in the source should be reduced when hydrogen is
used to prevent chemical ionization or other detrimental reactions from occurring. This
may be done by the use of narrower bore columns (0.18 mm ID or smaller), reduction in
the flow to the MS, and/or by the use of internal MS vacuum pumps (turbo pumps) with
greater volumetric or pumping efficiency. Hydrogen may not be a suitable carrier gas
for systems that have internal diffusion pumps.

B1.1.2 Use of hydrogen will clean (scrub) the metal surfaces of the analytical
system of compounds that have adhered to the surface, generally hydrocarbons, and
increase the background presence of these interferences. A bake-out of the system
using high flows of hydrogen may decrease these interferences to a level that would not
interfere with analysis. It is also recommended that new filters be installed on gas lines
(or remove them altogether if gas purity is sufficient) to prevent the scrubbing of impurities
from the filters.

B1.2 Use of hydrogen as the carrier gas may also reduce the responses of target
analytes (i.e., approximately 2 - 5 times) as compared to helium. RF criteria listed in Table 4
were developed using helium carrier gas and are not appropriate for hydrogen carrier gas due
to the reduced response of some analytes. If minimum RFs are used in evaluating the
calibration, the laboratory should develop their own criteria or use published RFs from the
instrument manufacturer. Reactivity of target analytes will vary with instrument conditions. As
part of the demonstration of capability (DOC) process, evaluate target analytes for stability
under the expected analytical conditions.

B1.3 As with any method modification, all QC procedures listed in Sec. 9.0 of this
method should be repeated and passed using hydrogen as the carrier gas prior to the analysis
of samples. Use of alternate solvents for calibration standards and extracts would also require
repeating these QC procedures prior to analysis of samples.

B1.4 Hydrogen gas is highly flammable and additional safety controls may be
necessary to prevent explosive levels of gas from forming. This may be accomplished by
connecting vent lines from the GC inlet and MS rough pump to exhaust systems in the
laboratory and leak testing all gas line connections. The flow of hydrogen should also be
turned off at the source prior to opening gas lines on the GC and prior to venting the MS (such
as when maintenance is performed). The user should consult additional guidelines for the safe
use of hydrogen from the instrument manufacturer prior to implementing its use.

SW-846 Update VI

8260D - 52

Revision 4
February 2017

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