The best steam class to date and what an exciting time learning from the hands on boilers @ GCAP. Thank you for using GCAP as your education stepping stone. Most state and employers require stationary engineers and boiler operators to have at least a high school diploma or equivalent and are trained either on the job or through an apprenticeship program. Many employers require stationary engineers and boiler operators to demonstrate competency through licenses or company-specific exams before they are allowed to operate equipment without supervision.