Which hazard is addressed by permit-required confined space entry?

• A. Electrical shock hazards
• B. Noise exposure
• C. Oxygen deficiency, toxic atmosphere, or dangerous engulfment hazards
• D. Extreme heat

Answer: (C)

Entering a permit-required confined space centers on the dangers that can lurk inside a confined space and require controlled protection. The key hazards are atmospheric: the air inside can be deficient in oxygen or contain toxic or flammable contaminants. Another major risk is engulfment, where liquids or loose materials inside the space could surround and bury a worker. These hazards are serious enough that a formal permit system, atmospheric testing, ventilation, isolation, and standby rescue are needed before entry.

Electrical shocks, noise, and extreme heat can occur in many places, not just within confined spaces, and they don’t by themselves define a space as permit-required. The permit-required designation specifically targets atmospheric hazards and engulfment risks (along with other severe interior hazards), which is why those are the hazards addressed by permit-required confined space entry.