AO Trainee-- Entry $21–$22 -- Orientation, safety, basic systems and supervised rounds Junior AO-- Developing -- $22–$23 -- Demonstrates defined system knowledge and operating tasks Junior AO-- Qualified -- $23–$24 -- Qualified to perform the complete AO role independently Senior AO -- $24–$27 -- Advanced systems knowledge, proven performance and training capability CRO Development -- $30+ -- Selected for control-room qualification . Relevant experience may include plant operator, process operator, boiler operator, utilities operator, stationary engineer, production technician, wastewater operator, industrial maintenance technician, heavy-equipment operator, military power production, or other industrial operations.