MASS Power Plant Safety 2 — Questions and Answers
Question 1: Before performing maintenance on a steam turbine, which procedure ensures the equipment cannot be accidentally energized?
- Lockout/Tagout (LOTO) (Correct answer)
- Posting a verbal warning
- Reducing the load to 50%
- Closing the control room door
Correct answer: Lockout/Tagout (LOTO)
Lockout/Tagout physically locks and tags energy isolation points so equipment cannot be re-energized during servicing.
Question 2: What is the primary purpose of a confined space entry permit in a power plant?
- To track tool inventory
- To verify atmospheric testing and rescue provisions before entry (Correct answer)
- To schedule overtime
- To log visitor access
Correct answer: To verify atmospheric testing and rescue provisions before entry
The permit confirms the space has been tested for hazardous atmospheres and that rescue and ventilation measures are in place.
Question 3: A worker notices steam escaping from a high-pressure line joint. What is the correct first action?
- Tighten the joint immediately by hand
- Evacuate the area and report it through proper channels (Correct answer)
- Spray water on the leak
- Stand closer to assess the temperature
Correct answer: Evacuate the area and report it through proper channels
High-pressure steam can cause severe burns, so personnel should leave the area and report the hazard for controlled isolation.
Question 4: Which gas is the primary asphyxiation concern when entering a nitrogen-purged vessel?
- Carbon dioxide
- Oxygen displacement by nitrogen (Correct answer)
- Methane buildup
- Excess hydrogen
Correct answer: Oxygen displacement by nitrogen
Nitrogen displaces oxygen, creating an oxygen-deficient atmosphere that can cause rapid unconsciousness.
Question 5: What does a Class C fire extinguisher rating indicate it is suitable for?
- Ordinary combustibles
- Flammable liquids
- Energized electrical equipment (Correct answer)
- Combustible metals
Correct answer: Energized electrical equipment
Class C extinguishers are rated for fires involving energized electrical equipment using non-conductive agents.
Question 6: Why must hearing protection be worn in turbine and pump halls?
- To block radio chatter
- Because sustained high noise levels can cause permanent hearing loss (Correct answer)
- To keep workers warm
- To filter dust particles
Correct answer: Because sustained high noise levels can cause permanent hearing loss
Rotating equipment produces noise above safe exposure limits, leading to irreversible hearing damage over time.
Question 7: What is the main reason for grounding electrical equipment in a power plant?
- To improve appearance
- To provide a safe path for fault current and prevent shock (Correct answer)
- To increase voltage output
- To reduce maintenance frequency
Correct answer: To provide a safe path for fault current and prevent shock
Grounding directs fault current safely to earth, reducing the risk of electric shock and equipment damage.
MASS Power Plant Safety 2
Before performing maintenance on a steam turbine, which procedure ensures the equipment cannot be accidentally energized?