The Environmental Protection Agency (EPA) requires that HVAC operators become certified in accordance with Section 608, a competency test. The test has four sections, and various study guides exist for operators of all levels.
ACCA Study Guide
The Air Conditioning Contractors of America (ACCA) produces a book called "ACCA--Study Guide for EPA Section 608 Test," which condenses all of the information required for the type I, II or III certification tests. The book is specifically designed for technicians with a working understanding of the industry. It is 28 pages long and available for $22 as of December 2010.
Video General Incorporated (VGI) is an organization selected to perform the EPA Section 608 test. The company has an outline of what is necessary to become certified. Technicians must pass a CORE test and then one of the four types of tests performed under Section 608. VGI produces the "EPA Section 608 Applicant Study Guide" to aid in preparing for and passing the test.
McGraw-Hill publishes the "HVAC Licensing Study Guide," which includes 408 pages of practice questions and lists of the most recent codes and regulations. The 800 included questions and answers are, according to the publisher, "most likely to appear on the licensing exams." The book is available for $40 as of December 2010.