flight regulations

Are CO2 cartridges for fillig bike tires prohibited on checked luggage or carry-ons? Can't really figure that out from the airline website.

I don't know for sure, but I've been told that not only can't you fly with them, the FedEx rep told me you can't even ship them by air. I just buy new ones at my destination.

Actually, the last time I was in that situation, my sister's LBS let me borrow two cartridges for the ride, and pay for them only if I needed them - since I didn't, they let me return them unused!

I would guess not. Can you just buy them at your destination?

I am accompanying my husband on a trip, which will be work for him and play for me. I hear the town is very bike friendly. I think there are several bike stores in the town. I don't know how to change a tire but if I had all the equipment I could probably get help. My bike will be the only mode of transportation I will have access to and I don't know the town very well. But it is someplace I'd really like to be so I'm excited! My bike is being shipped out in one of the cars my husband will be working on. If I have to buy cartridges I can send them back with the bike on the semi probably.

no - they will be confiscated from your carry on. (been there done that - forgot it was in my carry on)
I would not try to put them in your bike case either - if they think they are in there - they could unpack your bike......

I have been told by TSA agents checking my bike that CO2 cartridges are definitely not allowed. I have always just purchased them at my destination.

Welp, I accidentally just took two flights with two in my checked bag. Forgot they were in my bike repair kit because I've never actually used them. No one noticed and nothing happened to them.