RETA CIRO study guide
RETA CIRO · Work through your exam, one topic at a time.
The Certified Industrial Refrigeration Operator (CIRO) is a RETA credential for experienced industrial refrigeration operators who are ready to demonstrate supervisory-level knowledge. CIRO requires documentation of at least two years of experience as an industrial refrigeration operator. It assesses more advanced concepts, principles, and applications required to supervise industrial refrigeration operations, and it measures mastery of applied system operations and troubleshooting. The content is based on principles and knowledge addressed in RETA's Industrial Refrigeration I, Industrial Refrigeration II (Systems), Industrial Refrigeration IV (Plant Operation and Safety), Basic Electricity I, and Basic Electricity II (ladder diagrams). The RETA CIRO study guide has 5 sections and about 1,550 words.
01Industrial Refrigeration I - Fundamentals of the Refrigeration Cycle
Industrial refrigeration rests on a few ideas that exam questions probe relentlessly. Heat is energy in transit; temperature is its intensity.
293 words, about 1 min02Industrial Refrigeration II - Systems, Vessels, and Arrangements
Systems questions test whether you can name the arrangement and explain why it is used. Direct expansion feeds only the refrigerant that will boil off.
309 words, about 2 min03Industrial Refrigeration IV - Plant Operation and Safety
Plant operation questions blend procedure with consequence. Normal running means rounds: log suction and discharge pressures, oil levels, liquid levels, water treatment, and watch for frost lines, vibration, and leaks.
296 words, about 1 min04Basic Electricity I - Ohm's Law, Power, and Circuits
Basic electricity questions reward fluency with Ohm's law (E = I × R), power relationships (P = E × I and P = I²R), and the behavior of series and parallel circuits. In series, current is common and voltages add, and resistances add.
310 words, about 2 min05Basic Electricity II - Reading and Troubleshooting Ladder Diagrams
Ladder diagrams are drawn between power rails, with each rung read left to right (or top to bottom). Contacts in series must all be closed - a logical AND.
342 words, about 2 min