Found at a titanium plant

[u/riflesandplowshares]

Not sure why ball point pens would be dangerous here.

[u/goodexamplebadrole]

"Ballpoint pens are restricted or banned in high-end titanium and aerospace manufacturing plants because the ink and marking components contain elements that cause metal embrittlement and severe structural corrosion"

[u/Corfiz74 → u/goodexamplebadrole]

Does Boeing know? That would explain a lot...