agree with "mawheels1" poster...i do per diem icu work and my 'orientation' is arriving to the facility at least 1 hour early to figure things out...where to hang my coat, where to put my lunch, medication cart & code for it or grab a nurse to log me into pixys, where supplies are, write down most important hospital numbers -- lab, pharmacy, dietary, md on call, and how to dial them (yes, some phone systems are that complicated!!!) iv pumps and where to get my piece of paper so i can paper chart (cuz if they required an agency staff to do computer charting then they def. should have oriented you to that).
this amount of time is the minimum required to orient yourself to a new place, and in most agency circumstances its expected that you would do that to get familiar...i consider myself lucky at times, that they let me just come in as early as i want and start lurking/poking around to figure things out, so my advice is to use that precious time to help your shift go smoothly. you mention you have icu experience, so you know, many things run similarly from icu unit to unit and having that experience helps. if lower-pay orientation is available i would DEFINITELY take that...in fact i would do it for free to help myself and ensure a smooth shift, especially if there is opportunity for lots of work in that particular department...then its really kind of like paid training, considering i'll be getting lots of work over time.
you'll do fine. good luck