User`s guide

Installation and Setup

5. Do a Column Leak test the system. See the procedure,

Column Leak Test later in this chapter.

6. Connect the column to the GC detector as described in

the GC manual. Replace the cover plates.

NOTE: For columns that require an inlet pressure of less than 35

kPa (5 psig), better carrier gas control can be achieved by

inserting a length of narrow bore fused silica tubing, for

example 0.1-mm bore, 100 cm long, between the column

and the detector to increase the inlet pressure. The parts for

this restrictor are not included in the kit.

We recommend that you use the 0.53mm ID Retention Gap

kit, Part No. 0497-8449.

Connect to the ATD/TD Gas Supply

System

NOTE: Thermal desorption is a very efficient technique for

trapping compounds from gaseous samples. This will

include any contaminants in the carrier gas and so it is

extremely important to use only very pure carrier gas.

Filtered helium or nitrogen with a minimum purity of 99.995% or

better will be required. Use only approved gas lines to install the gas

supply system for the TD. You must use the same type of carrier gas

for the ATD/TD that is required for the GC analysis. See Table 9.

Carrier gas for a ATD/TD system performing trace analysis or using

either a mass spectrometer or an electrolytic conductivity detector

(ElCD) must have a minimum purity of 99.999% and must be

properly filtered.

Always use either copper or stainless steel tubing which is free of

grease, oil and organic material for all gases delivered to the TD/GC

system. Strain relief, consisting of two one-inch coils of tubing,

WARNIN

Observe proper handling procedures for compressed gas

cylinders. See Handling Compressed Gases on page 25.