Assuming our intrepid paramedic will be going into the US on the Visa Waiver form it'll take just as long as it normally does to get past the INS queues. Getting your first set of dabs and iris scan was really quick last time I went through (my first time since the changes). I think it added about five mins at most. If it takes 5hrs then there's other problems. Apart from the scans - it's the normal queue for INS which can be really quick or really slow - but not 5 hrs. Seatac is busy but not that busy...