This is the Royal Caribbean thread, right? I think the OP asked if she "could" bring an iron and blowdryer on the Enchantment of the Seas. I don't think she asked about NCL or CCL, but that's just me.
Anyway, it is good advice to bring your own hair dryer on EOS. While RCI provides a hairdryer, it is a toy.
Regarding the iron, you "could" bring one, and you would probably have no problem. But, RCI specifically says in their Guest Ticket Booklet, "For a very sensible fee, we'll do your laundry and dry cleaning in just one day. We do not provide irons in staterooms as they constitute a fire hazard. There are no self-laundry facilities aboard."
Enjoy EOS - we did in 2005.
Rhapsody - W. Caribbean - 2004; Rhapsody - W. Caribbean - 2005; Sovereign - Bahamas - 2005; Enchantment - Canada/NE - 2005; Rhapsody - W. Caribbean - 2006: Vision - Alaska - 2006
Navigator - E. Caribbean - 11/2006
Vision - West Coast Repo - 4/2007
Grandeur - Canada/N.E. - 9/2007
Voyager of the Seas -"R"W. Caribbean - 1/2008