1. What is Relative Humidity?

Relative Humidity (RH) is the ratio of the current absolute humidity to the highest possible absolute humidity (which depends on the current air temperature). It is expressed as a percentage.

2. How Does the Calculator Work?

The calculator uses the Relative Humidity formula:

Where:

• \( w \) — Specific humidity (kg/kg)
• \( w_s \) — Saturation humidity (kg/kg)
• \( RH \) — Relative humidity (%)

Explanation: The equation calculates what percentage the current humidity is of the maximum possible humidity at that temperature.

3. Importance of RH Calculation

Details: Relative humidity is important for many applications including weather forecasting, HVAC system design, industrial processes, and human comfort assessment.

4. Using the Calculator

Tips: Enter specific humidity and saturation humidity values in kg/kg. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between specific and relative humidity?
A: Specific humidity measures the actual water vapor content, while relative humidity measures how close the air is to saturation.

Q2: What are typical RH values?
A: Comfortable indoor RH is typically 30-50%. Below 30% may feel dry, above 60% may feel muggy and promote mold growth.

Q3: How does temperature affect RH?
A: Warmer air can hold more moisture, so RH changes with temperature even if the actual moisture content stays the same.

Q4: What instruments measure humidity?
A: Hygrometers, psychrometers, and more advanced electronic sensors can measure humidity parameters.

Q5: Why is RH important in industrial processes?
A: Many materials and processes are sensitive to moisture levels, affecting quality, drying times, and chemical reactions.