Performance Verification
7
SCD and NCD User Manual
109
Check SCD Performance
1
Gather the following:
•
Evaluation column, DB-1 30 m × 0.32 mm × 1.0
μ
m (part
number 123-1033)
•
SCD performance evaluation (checkout) sample
(5190-7003): 0.7 ± 0.002 mg/L diethyl disulfide and
1.0 ± 0.003 mg/L tert-butyldisulfide in isooctane.
•
Chromatographic-grade isooctane
•
4-mL solvent and waste bottles or equivalent for
autoinjector
•
2-mL sample vials or equivalent for sample
•
Inlet and injector hardware (See
2
Verify the following:
•
Chromatographic-grade gases plumbed and configured:
helium as carrier gas, air as oxidizer, and oxygen as ozone
supply gas.
•
Ozone supply gas moisture trap and other traps are in
date.
•
Empty waste vials loaded in sample turret.
•
4-mL solvent vial with diffusion cap filled with isooctane
and inserted in Solvent A injector position.
•
4-mL solvent vial with diffusion cap filled with isooctane
and inserted in Solvent B injector position.
3
Replace consumable parts (liner, septum, traps, syringe, and
so forth) as needed for the checkout. See
4
Install the evaluation column. (See the procedure for in the
GC
Maintaining Your GC
manual.)
•
Bake out the evaluation column for at least 30 minutes at
180 °C. (See the procedure for in the GC
Maintaining
Your GC
manual.)
•
Configure the column.
5
Check the detector baseline output. The output should be
below 150 pA and relatively stable, assuming a
well-stabilized system with the column oven at 50 °C.
However, a new burner (or a burner with a new ceramic
tube) can have a very high baseline after first ignition. In this
case, the baseline should gradually decrease, depending on