I don't know that you need to study up, just take good notes.
You'll cover Microbiology, Containment, HEPA filtration, Airmovement, Safety, Documentation.
I had a supervisor that thought he would breeze through the class since he was a CIE & CR. He failed it and had to retake the text. Everyone else we send scored in the 90's and said it was easy.
I never took it so I'd have to good with those that said easy since only one in four failed. lol