Only required to take a written test followed by one oral interview, quite easy actually. When I promoted to Paramedic from EMT I wasn't required to do any additional testing.

Have to take a company written test. Somewhat simple if you know you stuff. This is after they receive your application. Interview is group panel, then you have to run a mega-code to prove you know what your doing. If hired you set through 4.5 days of a new hire class. then you have to do your 240 hour ride time with a training officer to get county certified.