1. What is Fresh Air CFM Calculation?

The Fresh Air CFM calculation determines the required ventilation rate based on the number of occupants in a space, following ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) standards for indoor air quality.

2. How Does the Calculator Work?

The calculator uses the standard ventilation formula:

Where:

• \( \text{Occupants} \) — Number of people in the space
• \( 20 \text{ CFM/person} \) — Standard ventilation rate per person as per ASHRAE guidelines

Explanation: This calculation ensures adequate fresh air supply to maintain healthy indoor air quality by providing sufficient ventilation per occupant.

3. Importance of Fresh Air Intake

Details: Proper fresh air intake is essential for maintaining indoor air quality, removing contaminants, providing oxygen, and preventing the buildup of carbon dioxide and other pollutants that can affect health and comfort.

4. Using the Calculator

Tips: Enter the number of occupants in the space. The calculator will determine the required fresh air ventilation rate in cubic feet per minute (CFM) based on ASHRAE standards.

5. Frequently Asked Questions (FAQ)

Q1: What does CFM stand for?
A: CFM stands for Cubic Feet per Minute, which is a unit of measurement for airflow volume.

Q2: Why is 20 CFM per person used as the standard?
A: This value is based on ASHRAE Standard 62.1, which recommends 15-20 CFM per person for typical office environments to maintain acceptable indoor air quality.

Q3: Does the required CFM vary for different types of spaces?
A: Yes, different spaces have different ventilation requirements. For example, classrooms may require 10-15 CFM per person, while smoking lounges require much higher rates.

Q4: What factors besides occupancy affect ventilation requirements?
A: Space size, activity level, pollutant sources, and building materials can all influence ventilation needs beyond just occupant count.

Q5: How often should ventilation systems be maintained?
A: Regular maintenance including filter changes, duct cleaning, and system inspections should be performed according to manufacturer recommendations, typically every 3-6 months.