Final answer:
The recommended relative humidity in a building for health reasons is 30-70%. Proper humidity levels are vital for comfort and health, affecting air quality and the potential for mold growth or respiratory discomfort.
Step-by-step explanation:
From a health standpoint, the recommended relative humidity in a building is option B) 30-70%. Keeping indoor humidity within this range can help ensure a comfortable and healthy living environment. If the relative humidity is too high, it can promote the growth of mold and dust mites, which can cause respiratory issues. If it's too low, it can lead to dry skin, irritation of the respiratory tract, and can negatively affect wood furniture and floors.
Calculating relative humidity involves knowing both the current air temperature and the amount of moisture in the air. For example, if the relative humidity is 80% at 30.0°C, and the air cools to 25.0°C without losing moisture, the relative humidity will rise because cooler air can hold less moisture. This could lead to condensation, as water vapor becomes liquid water.
Such changes in temperature and humidity can impact comfort and health within buildings. Therefore, understanding relative humidity and maintaining it within the recommended range is important for indoor air quality.