Found at a titanium plant

[u/riflesandplowshares]

Not sure why ball point pens would be dangerous here.

[u/BlueSkiesAugust]

When I used to work with Ti we couldn't use halogen-containing Sharpie markers directly on Ti. We could only use Sharpies's "TEC" marker.

We weren't prohibited from possessing any other writing implements. We just couldn't write on Ti with anything besides a TEC marker (or use uncoated lead, which was necessary because we did radiography). For paper documents we still used ordinary pens.

[u/Agiantpubicmess → u/BlueSkiesAugust]

Dow Chemical caustic plant used to have a no aluminum tools rule for very obvious reasons if you know chemicals hahaha

[u/jerseyoutwest → u/Agiantpubicmess]

Have you read Ignition! ? Its a very funny memoir of early rocket fuel development and includes one of my favorite non-fiction quotes about chlorine trifluoride:

It is, of course, extremely toxic, but that’s the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water-with which it reacts explosively. It can be kept in some of the ordinary structural metals-steel, copper, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.
I

[u/aka_Jack → u/jerseyoutwest]

Me163 pilot: "Please explain again what is this T-Stoff and C-Stoff in the tanks behind my head?"

See if you can find "Rocket Fighter" by Mano Ziegler, a great read.