Originally Posted by nsc168

I should start off by saying that I knew I would need additional screening because of a 6 lb opened bag of salt I had in my carry-on. I am also Trusted Traveler, so what happened below happened in the TSA pre-check line. Specifically, STL international terminal.

What I didn't expect is for the salt to "alarm" when my case was tested with that little strip of paper and put in the machine. To clarify: the bag of salt was also subjected to two little paper tests (two inks: blue and clear) and it passed (in fact, I went through this process at 4 terminals in one day). What alarmed was the paper test that was wiped along the lining of my case, and when it was put in the machine, that's what alarmed.

This meant, my entire case was emptied out and all of my items individually x-rayed separate from the case. The case was also x-rayed. I also had to remove my shoes, put the shoes through the x-ray machine. And I got patted down.

The only thing I can figure is that the bag of salt may have leaked some salt granules, and that's what the little paper picked up.

So, question: to avoid my bag triggering the little paper test alarm, should I just clean the liner of my suitcase as best as I can, or should I dump this case and get a new case?