VOC/THM problems - Method 524.2

[coombs_ryan]

Big Bear

I'm currently at 40mL/min for purge flow
desorb temp is exactly the same as yours... 250

Here's a great question... why would this happen to both our systems at almost the same time (we have 2 separate identical systems side by side)?... I'm guessing it's an enviromental factor possibly? On the East coast here it's been raining constantly and the humidity is very high especially in the instrument lab.

What temp do you keep your condenser in your concentrator at during purge? During Bake? Mine is set at 0 degrees all though it can really only get down to about 28 degrees... during bake it's set at 200.

Do you run your calibration series standards from low to high or in accordance with 524.2 do you start with the mid point and then follow suit (remaining low to high) after that?

[Bigbear]

I start with a bake out @ 260 for 6 min, then I run a blank to check bfb tuning, then I run my standards low to high ( 0.5- 50 ppb).
My condensor parameters are ready temp 30
purge temp 20
bake temp 220

The room I work in is at about 20C most all the time. The humidity does varry through out the year.