1. What is the Heat Index?

The Heat Index (HI) is a measure that combines air temperature and relative humidity to determine the human-perceived equivalent temperature. It indicates how hot it feels when humidity is factored in with the actual air temperature.

2. How Does the Calculator Work?

The calculator uses the Heat Index equation:

Where:

• \( T \) — Temperature in degrees Fahrenheit
• \( RH \) — Relative humidity percentage
• \( HI \) — Heat Index in degrees Fahrenheit

Explanation: The equation accounts for how humidity affects the body's ability to cool itself through perspiration. Higher humidity makes it feel hotter than the actual temperature.

3. Importance of Heat Index

Details: The Heat Index is crucial for assessing heat-related health risks. It helps determine heat stress categories and appropriate precautions to prevent heat-related illnesses.

4. Using the Calculator

Tips: Enter temperature in °F and relative humidity as a percentage. The calculator works best for temperatures above 80°F and humidity above 40%.

5. Frequently Asked Questions (FAQ)

Q1: Why is heat index important?
A: It helps assess the risk of heat-related illnesses, which can be life-threatening. High heat index values indicate dangerous conditions.

Q2: What are the heat index danger levels?
A: Caution (80-90°F), Extreme Caution (90-103°F), Danger (103-124°F), and Extreme Danger (125°F+).

Q3: Does wind affect heat index?
A: The standard heat index assumes light wind (5-6 mph). Higher winds can make it feel cooler than the calculated heat index.

Q4: Can heat index be below the actual temperature?
A: No, heat index is always equal to or greater than the actual temperature.

Q5: Is this formula used worldwide?
A: This formula is primarily used in the US. Other countries may use similar indices like the "humidex" or "apparent temperature."