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Comment by kabwj | Hacker News Reader

Where does someone who thinks mailing Facebook sarin is a good idea get sarin from?

I'm betting that it's a false positive on a chemically similar substance. Field detection systems for chemicals/drugs/explosives don't tend to prioritize having a low false positive rate because they'd rather be safe than sorry and most customers have enough qualified immunity it doesn't really matter if the security guards dogpile on some little old lady because the system thought her perfume was a bomb.

This is the best theory. The detectors usually key on specific functional groups characteristic of the molecule rather than the molecule itself. This overfits for a lot of inert chemistry in practice, though they try to pick functional groups that are selective (and cheap to detect).

It can be synthesized, it is a simple molecule, though not trivially. There are several ways in which the process could kill an amateur chemist if they weren't very careful, it is significantly more dangerous than DIY explosives.

>A machine at a Facebook mailing facility in Menlo Park alerted employees Monday that a package might contain sarin

where do one gets such a machine and how one comes with the idea of getting it in the first place. As an employee of a BigCo. such idea has never crossed my mind (and we do have our share of angry/frustrated/on-the-verge-of-nervous-breakdown customers - i mean it is real enterprise software we're dealing in after all :)

I don't know the answer to your questions, but I recently read this and thought you may find it interesting, given your first question, as at some point Kurt Petersen developed devices that scan US mail for anthrax: https://spectrum.ieee.org/geek-life/profiles/kurt-petersen-2...

You'd get a generic chemical trace detection machine primarily to detect mail bombs, which sounds pretty reasonable when you're any sort of highly visible company.

Once you're known enough, you will draw the ire of some unstable person wanting to do bad things to you, no matter what you do.

> You'd get a generic chemical trace detection machine

Is this what the TSA uses when they swab my dog/my hands? I always assumed it was to look for a bomb but I’ve never asked because I figured using the “b” word at the airport would only bring more trouble.

I was once pulled aside for secondary screening by the TSA, and I was so bewildered that they asked if I'd taken a cab to the airport—and I had. The agent explained that it's a common cause of false positives like mine—"residue" gets left behind on the seats. I didn't feel like pressing them for more details, though.

Hand creams can set off that alarm.

They often contain glicerine, which can be a compund in explosives.

I'm not sure what the TSA use but I'm pretty sure they don't really work.

I've had multiple friends confirm a negative test for GSR when they'd just been at the shooting range in the same jacket/etc.

We still have people accidentally bring guns/knives on planes...

Corporations are, to a large extent, risk externalising engines. An LLC literally has minimising risks (liabilities) in its name.

Corporate security, insurance carriers (risk management on sterroids), investors or lenders (also fundamentally risk-oriented), might suggest or require mitigations.

Devices are sold through the usual channels:

https://duckduckgo.com/?q=mail+screening+chemical+detection&...

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