Fill volume is a range, not a number, and the range is set by the needle
A 10 mL headspace run on a 20 mL crimp vial came back with recovery at 71% for the lightest analyte, and the client’s method said 92% minimum. The septum had been punctured 14 times by the autosampler needle before the run ended, and the injection port was drawing vapor from a headspace that had grown by roughly 1.4 mL because the fill volume was set 2 mL short of where it should have been. Nothing was wrong with the vial material. The vial was simply the wrong size for the sample vol...
