Chromatography Forum

We're not a USEPA lab, and so our methods are only guided by USEPA methodology. More and more USEPA criteria are creeping into our regulation though.

The minimum RRF for 1122 Tetrachloroethane is our current case in question where 8260 specifies a minimum of 0.3 whereas ours (using the USEPA ions) is down around 0.15. We have linearity down to around 1-2ppb in waters, have good reproducibility so I'm not worried about our results, however I'm looking for ideas specifically for this compound.

Typically running 6890/5973 Agilent GC/MS with Tekmar Velocity Purge and Traps and Archon Autosamplers purging water samples directly in a vial (Archon in soil mode).

Any ideas? Is this a common problem?

How are you dealing with all the water getting to the MS. Read posts in this area dealing with Method 524.

Low recovery for this compound can be due to active sites, or a tired trap.

check trap. Most common cause

Active sites in the archon soil transfer line can cause major issues with the RF 1,1,2,2-Tetrachloroethane. If less then 0.3 I would recommend replacing it. It's a simple fix.