Yes you can!
I have just returned back from a 16 night cruise on Arcadia, and had straight hair every evening! !
Went on Oceana in April with our two grandaughters aged 11 and 12. The eldest took hours with make up and hair straighteners she dindnt have a problem with them heating up. It was me who had to wait to warm my curling tongs. Then she had the cheek to say I took too long doing my hair! You will love the Oceana, cant wait to go on her again!
Went on the Oceana in May,had no trouble with my tongs or hot brush.She is a fantastic ship.Hope you enjoy your cruise.
Yes you can, i had no problems with mine, you'll have a great time.