Enter the air temperature and relative humidity into the calculator to determine the discomfort index.
Discomfort Index Formula
The following equation is used to calculate the Discomfort Index.
DI = T - .55 * (1-.01*RH) * (T-14.5)
- Where Di is the discomfort index
- T is the air temperature (C)
- RH is the relative humidity
What is a Discomfort Index?
Definition:
A discomfort index measures how much discomfort a person feels with a given air temperature and relative humidity. The higher the relative humidity and the air temperature, the greater the discomfort index. Conversely, the lower the temperature and humidity the lower the discomfot.
How to Calculate Discomfort Index?
Example Problem:
The following example outlines the steps and information needed to calculate Discomfort Index.
First, determine the air temperature. In this example, the air temperature is measured to be 40C.
Next, determine the relative humidity. In this case, the relative humidity is calculated to be 40%.
Finally, calculate the discomfort index using the formula above:
DI = T – .55 * (1-.01*RH) * (T-14.5)
DI = 40 – .55 * (1-.01*40) * (40-14.5)
DI = 31.585
FAQ
What factors can affect the Discomfort Index?
The Discomfort Index is primarily affected by air temperature and relative humidity. However, factors such as wind speed, solar radiation, and personal factors like clothing and activity level can also influence how comfortable or uncomfortable a person feels in a given environment.
Can the Discomfort Index be used to predict health risks?
While the Discomfort Index is a useful tool for gauging comfort levels, it is not directly designed to predict health risks. High values on the index can indicate conditions that might lead to heat-related illnesses if proper precautions are not taken, such as staying hydrated and avoiding excessive exposure to heat.
How can individuals mitigate the effects of high Discomfort Index readings?
To mitigate the effects of high Discomfort Index readings, individuals can take several actions: stay in shaded or air-conditioned areas during the hottest parts of the day, wear lightweight and light-colored clothing, drink plenty of water, and avoid strenuous activities during peak heat hours. Planning outdoor activities for cooler parts of the day can also help reduce discomfort.
