Standard Practice for Installing Fused Silica Open Tubular Capillary Columns in Gas Chromatographs

SIGNIFICANCE AND USE
5.1 This practice is intended to be used by all analysts using fused silica capillary chromatography. It contains the recommended steps for installation, preparation, proper installation, and continued column maintenance.
SCOPE
1.1 This practice covers the installation and maintenance of fused silica capillary columns in gas chromatographs that are already retrofitted for their use. This practice excludes information on:  
1.1.1 Injection techniques.  
1.1.2 Column selection.  
1.1.3 Data acquisition.  
1.1.4 System troubleshooting and maintenance.  
1.2 For additional information on gas chromatography, please refer to Practice E260. For specific precautions, see 7.2.2.2(1), 7.2.2.2(2), 7.2.7, and 7.2.7.2.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific safety information, see Section 6, 7.2.2.2(1), 7.2.2.2(2), 7.2.7, and 7.2.7.2.2  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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Publication Date
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ASTM E1510-95(2021) - Standard Practice for Installing Fused Silica Open Tubular Capillary Columns in Gas Chromatographs
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This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:E1510 −95 (Reapproved 2021)
Standard Practice for
Installing Fused Silica Open Tubular Capillary Columns in
Gas Chromatographs
This standard is issued under the fixed designation E1510; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2.1 ASTM Standards:
1.1 This practice covers the installation and maintenance of
E260Practice for Packed Column Gas Chromatography
fused silica capillary columns in gas chromatographs that are
E355PracticeforGasChromatographyTermsandRelation-
already retrofitted for their use. This practice excludes infor-
ships
mation on:
2.2 CGA Publications:
1.1.1 Injection techniques.
CGAP-1SafeHandlingofCompressedGasesinContainers
1.1.2 Column selection.
CGA G-5.4Standard for Hydrogen Piping Systems at Con-
1.1.3 Data acquisition.
sumer Locations
1.1.4 System troubleshooting and maintenance.
CGA P-9The Inert Gases: Argon, Nitrogen and Helium
CGA V-7Standard Method of Determining Cylinder Valve
1.2 For additional information on gas chromatography,
Outlet Connections for Industrial Gas Mixtures
please refer to Practice E260. For specific precautions, see
CGA P-12Safe Handling of Cryogenic Liquids
7.2.2.2(1), 7.2.2.2(2), 7.2.7, and 7.2.7.2.
HB-3Handbook of Compressed Gases
1.3 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
3. Terminology
standard.
3.1 Terms and relations are defined in Practice E355.
1.4 This standard does not purport to address all of the
3.2 Nomenclature for open tubular or capillary columns
safety concerns, if any, associated with its use. It is the
with a bore of 0.75 mm or less:
responsibility of the user of this standard to establish appro-
3.3 porous layer open tubular (PLOT)—refers to columns
priate safety, health, and environmental practices and deter-
with particles attached on the inside wall consisting of copo-
mine the applicability of regulatory limitations prior to use.
lymers such as styrene/divinylbenzene, molecular sieves, or
For specific safety information, see Section 6, 7.2.2.2(1),
adsorbentssuchasAl O infilmthicknessesof5µmto50µm.
2 2 2
7.2.2.2(2), 7.2.7, and 7.2.7.2.
3.4 support coated open tubular (SCOT)—refers to fine
1.5 This international standard was developed in accor-
particles (silica or fine diatomite) coated with liquid stationary
dance with internationally recognized principles on standard-
phase, which is then deposited on the inside column wall to
ization established in the Decision on Principles for the
improve stationary phase stability and sample capacity.
Development of International Standards, Guides and Recom-
3.5 wall coated open tubular (WCOT)—refers to columns
mendations issued by the World Trade Organization Technical
coated on the inside wall with a liquid stationary phase in film
Barriers to Trade (TBT) Committee.
thicknesses of 0.1µm to 10.0 µm.Also referred to as FSOT or
fused silica open tubular.
This practice is under the jurisdiction ofASTM Committee E13 on Molecular
Spectroscopy and Separation Science and is the direct responsibility of Subcom-
mittee E13.19 on Separation Science. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved April 1, 2021. Published April 2021. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
ɛ1
approved in 1993. Last previous edition approved in 2013 as E1510–95 (2013) . Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/E1510-95R21. the ASTM website.
2 4
Reprinted by permission of Restek Corp., 110 Benner Circle, Bellefonte, PA Available from Compressed Gas Association (CGA), 8484 Westpark Drive,
16823-8812. Suite 220, McLean, VA 22102, http://www.cganet.com.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1510−95 (2021)
TABLE 1 Typical Splitter Vent Flow Rates (50 to 1 split ratio)
(at optimum linear velocity)
0.25 mm ID, 0.32 mm ID, 0.53 mm ID,
Carrier gas
3 3 3
cm /min cm /min cm /min
helium 35 80 125
hydrogen 70 160 250
Carrier gas: Hydrogen Carrier gas: Helium
Linear velocity: 40 cm/s Linear velocity: 20 cm/s
NOTE1—Fig.2showsthattheresolutionissimilarbuttheanalysistime
is reduced by 50% when comparing hydrogen to helium in an isothermal
analysis using optimum flow velocities.
NOTE 2—Hydrogen provides similar resolution in one-half the analysis
time of helium for an isothermal analysis.
NOTE1—Thecurvesweregeneratedbyplottingtheheightequivalentto
NOTE 3—
a theoretical plate (length of column divided by the total number of
1. Tetrachloro-m- 8. Heptachlor epoxide 15. Endosulfan II
theoretical plates, H.E.T.P.) against the column’s average linear velocity.
xylene 9. γ-chlordane 16. DDD
The lowest point on the curve indicates the carrier gas velocity in which
2. α-BHC 10. Endosulfan I 17. Endrin aldehyde
the highest column efficiency is reached.
3. β-BHC 11. α-chlordane 18. Endosulfan sulfate
NOTE 2—Gases information available from Compressed Gas Associa- 4. γ-BHC 12. Dieldrin 19. DDT
5. δ-BHC 13. DDE 20. Endrin ketone
tion (CGA), 8484 Westpark Drive, Suite 220, McLean, VA 22102,
6. Heptachlor 14. Endrin 21. Methyoxychlor
http://www.cganet.com.
7. Aldrin
FIG. 1Van Deemter Profile for Hydrogen, Helium, and Nitrogen
Carrier Gases
NOTE 4—30 m, 0.25mm ID, 0.25 µm 5% diphenyl−95% dimethyl
polysiloxane 0.1-µL split injection of chlorinated pesticides.
Oven temperature: 210°C isothermal
4. Summary of Practice
Injector and detector temperature: 250 °C ⁄300 °C
−11
4.1 The packed gas chromatography system is described in ECD sensitivity: 512 × 10
Split vent: 100 cm /min
Practice E260 and is essentially the same as a capillary gas
chromatographysystemexceptformodificationstotheinjector
FIG. 2Hydrogen Versus Helium (Isothermal Analysis)
and detector to accommodate the low flow rates and sample
capacity associated with capillary columns. Refer to the gas
chromatography(GC)instrumentmanualforspecificdetailson
injector or detector pneumatics for capillary columns.
4.2 Prior to performing a capillary GC analysis, the capil-
lary column configuration must be determined. The stationary
phase type, stationary phase film thickness, column inside
diameter, and column length must be selected. It is beyond the
FIG. 3Capping Silanol Groups with Dimethyl Dichlorosilane
scope of this practice to provide these details. Consult a (DMDCS)
column or instrument supplier for details on selecting the
appropriate capillary column configuration.
Association, a member group of specialty and bulk gas
4.3 Apply caution during handling or installation to avoid
suppliers, publishes the following guidelines to assist the
scratching or abrading the protective outer coating of the
laboratory chemist to establish a safe work environment: CGA
column. Scratches or abrasions cause the fused silica capillary
P-1, CGA G-5.4, CGA P-9, CGA V-7, CGA P-12, and HB-3.
column to spontaneously break or fail during usage.
7. Installation Procedure for Fused Silica Capillary
5. Significance and Use
Columns
5.1 Thispracticeisintendedtobeusedbyallanalystsusing
7.1 Abriefoutlineofthestepsnecessaryforinstallingfused
fused silica capillary chromatography. It contains the recom-
silica capillary columns in capillary dedicated gas chromato-
mended steps for installation, preparation, proper installation,
graphs is as follows:
and continued column maintenance.
7.1.1 Cool all heated zones and replace spent oxygen and
moisture scrubbers,
6. Hazards
7.1.2 Clean or deactivate, or both, injector and detector
6.1 Gas Handling Safety—The safe handling of compressed sleeves (if necessary),
gases and cryogenic liquids for use in chromatography is the 7.1.3 Replace critical injector and detector seals,
responsibility of every laboratory. The Compressed Gas 7.1.4 Replace septum,
E1510−95 (2021)
7.1.17 Set injector and detector temperatures and turn on
detector when temperatures have equilibrated (Warning—Do
not exceed the phase’s maximum operating temperature),
7.1.18 Inject a non-retained substance (usually methane) to
set the proper dead time (linear velocity),
7.1.19 Check system integrity by making sure dead volume
peak does not tail,
7.1.20 Condition the column at the maximum operating
temperature for 2 h (consult column manufacturer’s literature)
to stabilize the baseline,
7.1.21 Reinject a non-retained substance (usually methane)
to set the proper linear velocity,
7.1.22 Run test mixtures to confirm proper installation and
NOTE 1—Septum bleed can obscure or co-elute with compounds of
interest, thus decreasing the analytical accuracy. column performance, and
NOTE 2—
7.1.23 Calibrate instrument and inject samples.
1. 2,4,5,6-tetrachloro- 8. Heptachlor 16. p,p-DDD
7.2 The following section provides in-depth information on
m-xylene (IS) epoxide 17. Endrin aldehyde
instrument preparation procedures for installing and operating
2. α-BHC 9. γ-chlordane 18. Endosulfan sul-
3. β-BHC 10. Endosulfan I fate
fused silica capillary columns in capillary dedicated gas
4. γ-BHC 11. α-chlordane 19. p,p-DDT
chromatographs:
5. δ-BHC 12. Dieldrin 20. Endrin ketone
6. Heptachlor 13. p,p-DDE 21. Methyoxychlor 7.2.1 Gas Purification—The carrier gas must contain less
7. Aldrin 14. Endrin 22. Decachlorobi-
than 1 ppm of oxygen, moisture, or any other trace contami-
15. Endosulfan II phenyl (IS)
nants. Otherwise, oxygen and moisture degrade column
performance, decrease column lifetime, and increase back-
NOTE 3—30 m, 0.53mm ID, 0.50 µm 5% diphenyl−95% dimethyl
polysiloxane 0.1 µL direct injection of 50 pg pesticide standard.
ground stationary phase bleed. Contaminants such as trace
hydrocarbons cause ghost peaks to appear during temperature
Oven temperature: 150 °C to 275 °C at
4 °C ⁄min,
programming and degrade the validity of the analytical data.
hold15min
Make-up gas should also be contaminant-free or baseline
Injector temperature: 250 °C Detector temperature: 300 °C
Carrier gas: Helium fluctuations and excessive detector noise may occur. Detector
Linear velocity: 40 cm/s (Flow rate: 10 cm /min)
gases such as hydrogen and compressed air should be free of
−11
ECD sensitivity: 8 × 10 AFS
water and hydrocarbon or excessive baseline noise may occur.
FIG. 4ECD Septum Bleed 7.2.1.1 Install purifiers as closely as possible to the GC’s
bulkhead fitting, rather than system-wide. If purifiers are
installed system-wide, a leaky fitting downstream of the
purifier could allow oxygen and moisture to enter the gas
stream and degrade column performance.
7.1.5 Set make-up and detector gas flow rates,
7.2.1.2 Only high–purity gases should be used for capillary
7.1.6 Carefully inspect the column for damage or breakage,
chromatography.All regulators should be equipped with stain-
7.1.7 Cutapproximately10cmfromeachendofthecolumn
less steel diaphragms. Regulators equipped with rubber or
using a ceramic scoring wafer or sapphire scribe,
elastomeric diaphragms should not be used because oxygen,
7.1.8 Install nut and appropriately sized ferrule on both
moisture, and elastomeric contaminants migrate through the
column ends,
diaphragm and enter the flow.
7.1.9 Cut an additional 10 cm from each end of the column
to remove ferrule shards, 7.2.1.3 Both indicating and non-indicating traps are avail-
able from most capillary column suppliers. Indicating purifiers
7.1.10 Mount the capillary column in the oven using a
bracket to protect the column from becoming scratched or are recommended since they allow analysts to visually assess
whether the purifier has exceeded its useful life. Also, a
abraded and to prevent it from touching the oven wall,
7.1.11 Connect the column to the inlet at the appropriate moisture trap should be installed prior to the oxygen trap. If
hydrocarbon contamination is suspected, a hydrocarbon trap
distance as indicated in the instrument manual,
7.1.12 Set the approximate column flow rate by adjusting should be installed between the moisture and oxygen trap.
Sincemostindicatingtrapsaremadefromglass,careshouldbe
the head pressure (see column manufacturer’s literature),
7.1.13 Set split vent, septa purge, and any other applicable taken not to apply lateral torque on the fittings, or they will
snap. To prevent spontaneous breakage of the trap, the line
inlet gases according to the instrument specifications,
7.1.14 Confirmflowbyimmersingcolumnoutletinavialof leading to and from the purifier should be coiled to relieve
strain and isolate instrument vibrations.
acetone or methylene chloride,
7.1.15 Connectthecolumntothedetectorattheappropriate 7.2.2 Carrier Gas Selection—Afastcarriergasthatexhibits
distance as indicated in the instrument manual, a flat van Deemter profile is essential to obtain optimum
7.1.16 Check for leaks at the inlet or outlet using a thermal capillary column performance. Because capillary columns
conductivity leak detector (do not use soaps or liquid-based average30minlength(comparedto2mforpackedcolumns),
leak detectors), a carrier gas that minimizes the effect of dead time is
E1510−95 (2021)
important. In addition, capillary columns are usually head
pressure controlled (not flow controlled like most packed
columns), which cause the carrier gas flow rate to decrease by
40% when the column is programmed from ambient to
300°C.Therefore,acarriergasthatretainshighefficiencyover
a wide range of flow rates is essential towards obtaining good
resolution throughout a temperature–programmed chromato-
graphic analysis.
7.2.2.1 The optimum average linear gas velocity for hydro-
gen (u : 40 cm/s) is greater than all the others, and hydrogen
opt
exhibits the flattest van Deemter profile. Helium is the next
best choice (u : 20 cm/s). Note that head pressures at
opt
optimum flow rates are similar for hydrogen and helium
Carrier gas: Hydrogen Carrier gas: Helium
because hydrogen has half the viscosity but double the linear
Linear velocity: 40 cm/s Linear velocity: 20cm/s
velocityashelium.Becauseofthelowoptimumlinearvelocity
(u : 10 cm/s) and steep van Deemter profile, nitrogen gives NOTE1—Hydrogenisonlyslightlyfasterthanheliumwhenbothcarrier
opt
gases are operated under the same temperature-programmed oven condi-
inferior performance with capillary columns and is usually not
tions.
recommended.
NOTE 2
...

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