User`s guide

Accessories
195
standard easy to distinguish in a chromatogram run on a GC-MS
system. Toluene-D8 does not exist in nature and so there is no
interference with naturally occurring compounds.
Description Part No.
0.5 mL Sample Loop P/N 0332-4902
1.0 mL Sample Loop P/N 0332-4903
5.0 mL Sample Loop P/N 0332-4904
NOTE: If you are using an internal standard at a concentration that
exceeds the TLV limits, you must direct the Tube Load and
Loop Load vents to a fumehood or another suitable
location.
Setting the IS Flow Rates
Before you begin operation of your instrument with the IS accessory,
you must establish the flow rates of standard gas through the IS loop
and then through the sample tube. The instructions below are for
both the ATD and TD.
A high quality regulator (not supplied) should be used on the
reference gas tank. Connect the supply of gas to the back panel of the
ATD/TD using 1/8” copper or stainless steel tubing. Set the delivery
pressure to 90 psig (620 kPa).
NOTE: Observe proper handling procedures for pressurized gases.
See Handling Compressed Gases on page 25.
IS Loop Fill— See the Status/Options tab, to check the Standard
Inject box.This will enable the Internal Standard Addition
accessory.
During loop fill, the system will flush and fill the loop. Typically you
will want to flush the loop with ten times the volume of the loop. i.e.
if your sample loop is 0.5 mL, then 5 mL should pass through the
loop in order to adequately flush the loop.
10XLoop Volume (mL) / Load Flow (mL/Min) = Time (Min)
Based on the above requirement, a loop flush/fill flow rate must be
adjusted so that an appropriate Loop Load fill time can be decided