I don't think you would be wise to take a small iron with you. They are normally banned on cruise ships as they are a fire hazard. The irons provided in ships laundries are specifically designed not to overheat.
Hi Carlisle, my wife has this problem too!
Personally I can't understand why she can't wait to get home before doing the washing and ironing. Also I seem to recall that P&O have some rules about ironing in the cabin - something to do with possile damage to the work surfaces.
You are cannot take a small or large iron on board due to fire risk, personally I would never dream of doing any laundry or ironing 'I am on holiday' if a few items seem creased when unpacking I find if I hang them in the bathroom while taking a shower the creases fall out, or I give them to housekeeping to iron, they don't charge too much.
Why not use their laundry service? If you keep an eye on the daily bulletin they do special offers as well so chose your time as other contributors have said you are on holiday enjoy
I myself do not do any washing or ironing whilst away on holiday, but for those who do, the ironing and washing facilities for such a large shipping was, in my view, totally inadequate - but that was not the problem we had, but a very smelly bathroom for the whole of the time (sewerage). Although the plumbers tried to remedy this five times the smell remained, and this did spoil the enjoyment of our holiday - at the moment P&O are looking into my complaint.