Empty your pockets!

People were asking about this sign...

...because what possible difference could it make if I carry my Parker T-Ball jotter around in a titanium factory?

And as a man with titanium knees, thank you for leaving that pen in the car. This is why: The teeny rolling ball in your standard Bic ballpoint pen tip is made of tungsten carbide, which is extremely hard, as you will remember from the time in 8th grade that you and that Wellington kid finally popped the roller out of your Papermate and tried to coat it with some mercury secreted from the science lab. You'll have to get a fire underneath tungsten that's 6,192°F to melt it, while they only have to heat titanium to 3,400°F. The deal is, if your pen falls into a molten titanium vat, the tungsten will not melt.  

And while that might not bother you (you can always get another free pen at the Credit Union), that teeny bit o' unmelted tungsten would get into jet airplane rotors or aircraft frames and even something that little can cause a lot of problems, such as fatigue cracks and other performance problems.

There was a guy at work once, went out at lunch came back with a cold cut sub. He asked for "everything" on the sandwich, and when he bit into it, he found more than everything...there was the plastic glove that the sandwich maker had been wearing until it fell off in the middle of my buddy's sandwich.

That's the parallel I draw for unwanted foreign items. Not blaming anyone, but check your lunch carefully (unless you packed it!)

And leave your pens outside whenever you find yourself at a titanium plant!