City of Chicago Boiler Practice Exam

Lockout/Tagout is a safety procedure that prevents unexpected energization or startup of equipment while maintenance or repair is performed. It involves isolating all energy sources and applying a lock or tag to indicate the equipment must not be operated. This ensures that even if someone could energize controls, the machine cannot start, protecting workers from moving parts, steam, hot surfaces, and stored-energy hazards.

For boiler work, this is essential because boilers involve high-pressure steam, electrical circuits, fuel valves, and energy-controlling valves. A re-energization or release during servicing can lead to severe burns, scalding, or explosions. Lockout/Tagout requires confirming the energy is isolated and remains off until maintenance is finished and the area is verified safe.

Other options don’t fit because routine training alone doesn’t stop energy; calibrating pressure relief valves is about protecting against overpressure, not preventing startup during maintenance; lighting standards address visibility, not energy isolation. The safety procedure to ensure equipment cannot be started while maintenance is performed is the core purpose here.