1. What is Relative Humidity?

Relative Humidity (RH) is the ratio of the current amount of water vapor in the air to the maximum possible amount of water vapor at that temperature, expressed as a percentage. It's a key parameter in meteorology, HVAC systems, and industrial processes.

2. How Does the Calculator Work?

The calculator uses the Relative Humidity formula:

Where:

• \( RH \) — Relative Humidity (%)
• \( P_v \) — Vapor pressure (Pa)
• \( P_{sat} \) — Saturation pressure (Pa)

Explanation: The equation calculates the percentage of moisture in the air relative to what the air can hold at saturation at the same temperature.

3. Importance of RH Calculation

Details: Accurate RH measurement is crucial for weather forecasting, comfort control in buildings, industrial processes, and preventing moisture-related damage in materials.

4. Using the Calculator

Tips: Enter vapor pressure and saturation pressure in Pascals (Pa). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between RH and absolute humidity?
A: RH is a percentage of moisture relative to capacity, while absolute humidity is the actual mass of water vapor per volume of air.

Q2: What are typical RH ranges for comfort?
A: For human comfort, 30-60% RH is generally recommended, with 40-50% often considered ideal.

Q3: How does temperature affect RH?
A: RH changes with temperature because warm air can hold more moisture than cold air, even if the actual water vapor content stays the same.

Q4: What instruments measure RH?
A: Hygrometers, psychrometers, and modern electronic sensors can measure RH directly.

Q5: Why is RH important in industrial processes?
A: Many manufacturing processes require precise humidity control to ensure product quality and prevent moisture-related issues.