CADR & Room Size: Exact Metric Calculations for Global Buyers

Many people have asked me what kind of air purifier is suitable for their room. Maybe you are also worried about not knowing what kind of air purifier to buy. Reading this article can answer your doubts.

Before that, if you don’t have the knowledge of CADR, I suggest you read this article, which will make it easier for you to understand how to choose an air purifier.→What is CADR?

Step 1: Measure Your Room in Cubic Meters

Volume Formula:

Length (m) × Width (m) × Height (m) = Volume (m³)

• Example: 5m × 4m × 2.5m = 50 m³

Pro Tip:

• Standard ceiling height: 2.5m (8.2ft)

• For irregular rooms, divide into rectangular sections.

Step 2: Apply the 7.2 Multiplier

AHAM-Validated Equation:

Required CADR = Room Size (m²) × 21.3

Case Study:

• Living Room (16 m²): 16 × 7.2 = 112 CADR

• Bedroom (10 m²): 10 × 7.2 = 70 CADR

Step 3: Validate Against Real-World Scenarios

Tip: This calculation result is the simplest calculation method. If you need to confirm the most suitable product, please contact us.

Why 7.2? The Science Explained

• Derivation: AHAM’s 1.49 factor adapted for metric:
  1 m² = 10.763 ft² → 10.763 ÷ 1.49 ≈ 7.2

• Certification: Validated by TÜV Rheinland for EU/Asian markets.

3 Critical CADR Myths (Metric Edition)

1. “CADR = m³/h”:

• Truth: m³/h measures airflow, not efficiency. CADR = m³/h × filtration rate.

2. “All Brands Use 7.2”:

• Fact: 31% of brands use unverified multipliers (2024 TÜV audit).

3. “Bigger Rooms Need Multiple Units”:

• Solution: Single high-CADR units (e.g., 1000+ CADR) can cover 130m² spaces.

FAQ: Metric CADR Essentials

Q: Does ceiling height affect CADR needs?
A: Yes—3m ceilings require 20% higher CADR vs. 2.5m standards.

Q: Is 7.2 valid for all particle types?
A: Yes—smoke/dust/pollen use the same multiplier.

Call to Action
Explore TÜV-Certified CADR Purifiers → Perfect for Metric Users