"A lot of lab managers are going to be scrambling to their Quality Manuals as a result of this."

From your mouth to God's ear.

In my view, if the TIC looks nothing at all like gasoline, the amount of "skewing" allowed should be "very little." As in, at the very least, the peaks should match in terms of which is the tallest, second tallest, etc.

The probability that the background would contribute just enough of one component to upset the rankings, but not blow the background off scale is not worth considering. Unless you can PROVE it with real experimental data. I have not seen that happen yet.

John Lentini, CFI, D-ABC
Fire Investigation Consultant
Florida Keys
[www.firescientist.com]