A 3rd Class Engineer, also known as a Third-Class Power Engineer, is a certified professional responsible for operating and maintaining industrial boilers, pressure vessels, and related equipment under the supervision of higher-class engineers. They work in settings such as power plants, manufacturing facilities, and heating plants to ensure safe and efficient operation of mechanical systems. To become a 3rd Class Engineer, individuals typically need to complete technical training, acquire hands-on experience, and pass a provincial or state certification exam. Their responsibilities include monitoring equipment, performing maintenance, troubleshooting issues, and adhering to safety regulations.