MIL-DTL-87173B(USAF)
APPENDIX A
A.3.1.5 Column. Either packed or open-tubular (capillary-type) columns may be used, provided the
minimum resolution, specified in section A.5.2, is maintained. The column should be designed for
maximum thermal stability and minimum bleed, since the temperature program is likely to run as high as
275 °C for packed column and 200 °C for capillary columns. Dual-column compensation is required if
column bleed results in excessive baseline drift at high temperatures.
A.3.1.6 Integrator. An electric integrator is required for highest accuracy and precision. Data
acquisition and reduction by an on-line computer, programmed for gas chromatography, is convenient
and may be used if such capability is available.
A.3.1.7 Microsyringe. A microsyringe, capable of delivering sample volumes from 0.5 to 5.0 microliters,
is required.
NOTE 3. The widely used 0 - 10 microliter syringe, Hamilton Model 701N or its equivalent, is
recommended. These syringes are routinely available from most instrument manufacturers and
chromatography supply houses.
A.4 REAGENTS AND MATERIALS
A.4.1 Stationary-phase. The stationary phase should be one of the familiar non-polar silicones. The
following silicones have been used successfully:
Silicone SE-30
Silicone UCW-982
Silicone OV-101.
NOTE 4. UCW-982 is recommended because it exhibits less column bleed at high temperatures than the
other silicones. However, any of the listed phases are satisfactory, provided baseline drift at high
temperature is minimized by conditioning or by dual column compensation.
A.4.2 Carrier gas. Either helium or nitrogen is suitable, although nitrogen is known to give somewhat
higher column efficiencies at lower flow rates, and is more economical. Helium must be used with
thermal conductivity detectors. The flow must be maintained constant to within one percent throughout
the entire range of operating temperatures by means of constant flow controllers.
A.4.3 Hydrogen. High purity, for flame ionization detectors
A.4.4 Air. Dry, filtered, and oil-free, for flame ionization detectors
A.4.5 Exo-tetrahydrodi(cyclopentadiene). (99 percent purity), hereafter referred to as C-10
NOTE 5. High purity samples of C-10 may be obtained by submitting a written request to AFRL/PRSF,
1790 Loop Rd. N., Wright-Patterson AFB OH 45433-7103.
A.4.6 Methylcyclohexane. (99 percent purity) hereinafter referred to as MCH
A.4.7 n-Pentane, n-hexane, or carbon disulfide. Chromatographic purity
A.4.8 Qualitative calibration mixture. A series of known hydrocarbons is used to calculate column
resolution. Prepare a mixture containing about one percent (by volume) each, in pentane, hexane, or
carbon disulfide of at least eight normal alkanes and six cycloalkane derivatives selected from highly
pure (minimum 99 percent) samples which have boiling points in the 70°C-250°C range. The mixture
must contain MCH, n-dodecane, and n-tetradecane.
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