Can I take hairpins on a flight?

Question

I'm not checking my bag.

Answer 1

Yes, you may.  See TSA site below for any other questions.  Anything not specifically prohibited, is allowed.

Answer 2

I don't know about in your baggage but you should not wear them in your hair, because they will pull you out of the line and search you  when you go through the metal detector.  My aunt had hair pins in a bun hair style and she ended up having to take your hair alose and got through the metal detector.  You might be ok is you are checking your baggage.