A permit-required confined space may contain hazards. Which of the following is an example of a hazard commonly associated with such spaces?

A permit-required confined space may contain hazards. Which of the following is an example of a hazard commonly associated with such spaces?

• A. Oxygen-deficient atmosphere
• B. Nonhazardous air
• C. Normal atmospheric pressure
• D. Adequate lighting

Answer: (A)

Permit-required confined spaces are defined by the potential for hazardous conditions inside, especially atmospheric ones. An oxygen-deficient atmosphere is a classic hazard in these spaces because the oxygen level drops below normal ambient air, making it hard to breathe. Normal air contains about 20.9% oxygen; when the concentration falls below roughly 19.5%, people can experience dizziness, confusion, fainting, or even death. That’s why entry into such spaces requires monitoring with a calibrated gas detector, adequate ventilation, and proper permits and rescue planning. The other conditions described are not hazards in themselves: nonhazardous air means the atmosphere is safe, normal atmospheric pressure is not hazardous, and adequate lighting does not constitute a space hazard.

Permit-required confined spaces are defined by the potential for hazardous conditions inside, especially atmospheric ones. An oxygen-deficient atmosphere is a classic hazard in these spaces because the oxygen level drops below normal ambient air, making it hard to breathe. Normal air contains about 20.9% oxygen; when the concentration falls below roughly 19.5%, people can experience dizziness, confusion, fainting, or even death. That’s why entry into such spaces requires monitoring with a calibrated gas detector, adequate ventilation, and proper permits and rescue planning.

The other conditions described are not hazards in themselves: nonhazardous air means the atmosphere is safe, normal atmospheric pressure is not hazardous, and adequate lighting does not constitute a space hazard.