You can take electric powered hair curlers that use mains power, i.e. they have a plug attached, they are not restricted, but hydrocarbon gas powered hair curlers are restricted.
All cylinders containing pressurised gas present a risk of exploding. It is not safe to take larger cylinders onto the plane.
You will be asked to relinquish all dangerous or prohibited items found in your carry-on luggage. If you refuse:
AvSec X-ray bags going onto aircraft to ensure there is nothing dangerous in them.
For more information, see Retrieving your removed items.