Mold Assessment Technician Practice Exam

What is a significant environmental trigger for relative humidity exceeding 90%?

1. High temperature with no dew point

2. Low temperatures with high winds

3. Temperature and dew point being nearly the same

4. Increased air circulation

The correct answer is: Temperature and dew point being nearly the same

Relative humidity levels exceeding 90% typically occur when the temperature and dew point are nearly the same. The dew point is the temperature at which air becomes saturated with moisture, leading to condensation. When the temperature approaches the dew point, the air can no longer hold all the moisture, resulting in high relative humidity. In conditions where the temperature and dew point are close together, even a small amount of moisture in the air can cause relative humidity to spike dramatically. This situation is often seen in humid climates where warm air holds a significant amount of moisture, and as the temperature shifts to match the dew point, the environment becomes highly saturated, contributing to possible mold growth and other moisture-related issues. In contrast, high temperatures with no dew point do not necessarily lead to high humidity levels, as dry conditions can occur regardless of heat. Low temperatures with high winds can disperse moisture and actually prevent the accumulation of high humidity. Increased air circulation typically aids in reducing moisture levels by promoting evaporation, which is the opposite of creating an environment conducive to high humidity.