: I am curious if anyone can suggest some easy reading reference material to use to study for a plpumbing code exam. : Also some good mechanical code reference material? I would first start with the codes in your area, Depends what you are studying for Im sure your local bookstores will stock some of your study materials.The plumbers handbook from Audel is great for apprentice to master plumbers. Your local examiners should of give you some insight on what will be on your tests. Ask your peers in your areas.