From Celebrity's FAQs/Prohibited Items:
"Candles, Incense, Coffee Makers, Clothes Irons, Travel Steamers & Hot Plates. (Items that generate heat or produce an open flame. This includes heating pads, clothing irons, hotplates, candles, incense and any other item that may create a fire hazard. NOTE: The only exception to this policy are curling irons and hair straighteners. Matches and normal lighteners are allowed onboard. However ""torch lighters"" and novelty lighters that look like guns are not allowed onboard. Torch lighters emit a powerful concentrated flame, and therefore are prohibited."
There are many other prohibited items, of course, but this is the section that applies to you!
https://www.celebritycruises.com/faqs/before-you-board
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