California ICC UST Service Technician Practice Exam

Which atmosphere condition can lead to asphyxiation?

1. High humidity

2. Oxygen depletion

3. Elevated temperature

4. Low pressure

The correct answer is: Oxygen depletion

Oxygen depletion is a critical condition that can lead to asphyxiation because it directly affects the body’s ability to get the oxygen necessary for survival. Humans typically require a minimum concentration of oxygen to function properly, which is around 19.5% in the atmosphere. When the oxygen level falls below this threshold, the body begins to starve for oxygen. This can cause a range of symptoms, from lightheadedness and confusion to unconsciousness and death. In contrast, while high humidity can make the environment uncomfortable and may contribute to heat-related illnesses, it does not directly deplete the oxygen content in the air. Elevated temperature can also pose health risks, particularly in terms of heat exhaustion or heat stroke, but it does not result in direct asphyxiation. Low pressure environments may result in a decrease in the total amount of available oxygen, but typically these conditions are associated more with altitude sickness rather than rapid asphyxiation. Therefore, oxygen depletion remains the most direct and immediate atmospheric condition that can lead to asphyxiation.