1. What is Fresh Air CFM?

Fresh Air CFM (Cubic Feet per Minute) calculation determines the required ventilation rate for indoor spaces according to ASHRAE standards. It ensures adequate air quality by providing sufficient fresh air based on occupancy and space area.

2. How Does the Calculator Work?

The calculator uses the ASHRAE ventilation formula:

Where:

• \( Occupants \) — Number of people in the space
• \( Area \) — Floor area in square feet (ft²)
• \( 15 \) — CFM per person requirement
• \( 0.06 \) — CFM per square foot requirement

Explanation: The formula accounts for both occupant-based ventilation (15 CFM per person) and area-based ventilation (0.06 CFM per ft²) to ensure comprehensive air quality management.

3. Importance of Fresh Air Calculation

Details: Proper fresh air calculation is essential for maintaining indoor air quality, preventing sick building syndrome, ensuring occupant comfort, and complying with building codes and ASHRAE standards.

4. Using the Calculator

Tips: Enter the number of occupants and the area in square feet. Both values must be non-negative numbers. The calculator will provide the required fresh air CFM for proper ventilation.

5. Frequently Asked Questions (FAQ)

Q1: What is ASHRAE Standard 62.1?
A: ASHRAE Standard 62.1 specifies minimum ventilation rates and indoor air quality requirements for acceptable indoor environments.

Q2: Why 15 CFM per person?
A: 15 CFM per person is the minimum ventilation rate required to dilute bioeffluents (body odors, CO2) and maintain acceptable indoor air quality.

Q3: When should area-based ventilation be considered?
A: Area-based ventilation accounts for emissions from building materials, furnishings, and other non-occupant sources that affect indoor air quality.

Q4: Are there different requirements for different space types?
A: Yes, ASHRAE provides different ventilation rates for various space types (offices, classrooms, restaurants, etc.) based on specific usage patterns.

Q5: How often should ventilation rates be recalculated?
A: Ventilation rates should be reviewed whenever occupancy patterns change, space usage is modified, or during building renovations.