Water Damage Restoration Technician (WRT) Certification Practice Test

To determine the temperature in degrees Fahrenheit given a humidity ratio of 70 grains per pound of dry air (GPP) and a relative humidity of 60%, one would typically use psychrometric principles and charts or calculations. The humidity ratio and relative humidity are linked to specific temperature values, and understanding the relationship between these variables is crucial.

The humidity ratio represents how much water vapor is present in the air compared to the dry air, while relative humidity indicates how much moisture is in the air relative to the maximum capacity of the air to hold moisture at that temperature. By utilizing psychrometric calculations or charts, it can be established that a humidity ratio of 70 GPP and a relative humidity of 60% corresponds to a temperature around 92°F.

This relationship arises because, at higher humidity ratios, warmer temperatures can accommodate more moisture while maintaining a certain relative humidity percentage. In this case, the combination of the given humidity ratio and humidity level points towards a higher temperature that can sustain those conditions, which further directs the outcome to about 92°F. Thus, option C accurately reflects this relationship in psychrometric properties.